ICRANet Scientific Report 2015 |
ICRANetThe 2015 Scientific ReportPresented toThe Scientific CommitteebyRemo RuffiniDirector of ICRANet
ICRANet has been created by a law of the Italian Government, ratified unanimously by the Italian Parliament and signed by the President of the Republic of Italy on February 10^{th} 2005. The Republic of Armenia, the Republic of Italy, the Vatican State, ICRA, the University of Arizona and the Stanford University have been the Founding Members. All of them have ratified the Statute of ICRANet (see Enclosure 1). On September 12^{th} 2005 the Board of Governors was established and had its first meeting. Professors Remo Ruffini and Fang Li-Zhi were appointed respectively Director and Chairman of the Board. On December 19^{th} 2006 the Scientific Committee was established and had its first meeting in Washington DC. Prof. Riccardo Giacconi was appointed Chairman and John Mester Co-Chairman. On September 21^{st} 2005 the Director of ICRANet signed with the Ambassador of Brazil Dante Coelho De Lima the adhesion of Brazil to ICRANet. The entrance of Brazil, requested by the President of Brazil Luiz Ignácio Lula Da Silva has been unanimously ratified by the Brazilian Parliament. On February 2009 the board renewed the position of Prof. Fang Li-Zhi as the Chairman of the Board. On December 2009 the Scientific Committee renewed the position of Prof. Riccardo Giacconi as the Chairman of the Committee. On February 2010 the board renewed the position of Prof. Remo Ruffini as the Director of the ICRANet. On August 12^{th}, 2011 the President of Brazil Dilma Rousseff signed the entrance of Brazil in ICRANet. On October 15^{th}, 2012, following the death of Prof. Fang LiZhi, Prof. Francis Everitt was appointed Chairman of the Board and Prof. XiaoHui Fan and Prof. ShuFang Su were indicated as temporary substitutes of Prof. Fang. On June 12^{th}, 2013, following the completion of his second mandate, Prof. Riccardo Giacconi has resigned as Chairman of the Scientific Committee on the completion of his 81^{st} birthday. Prof. João Braga was then appointed Chairman of the Scientific Committee and Prof. Massimo Della Valle was appointed Co-Chairman (details on http://www.icranet.org/). In December 2013, during the visit at the University of Arizona of Prof. Remo Ruffini, Director of ICRANet, it was agreed with the Dean of the University of Arizona to appoint Prof. XiaoHui Fan as the successor of Prof. Fang LiZhi in representing the University of Arizona in the ICRANet Board. In May 2014 Prof. João Braga resigned from the Scientific Committee. ICRANet launched an open call, with the support of the Brazilian Physical Society and of the Brazilian Astronomical Society, for a new representative of Brazil in the Scientific Committee. The call selected Prof. Kepler de Souza Oliveira Filho (see Enclosure 2). This candidature was submitted to MCTI (Brazilian Minister of Science and Technology and Innovations). In the meantime Prof. Kepler was appointed vice-president of the Brazilian Astronomical Society, which added to his already duties as Chairman of the CNPq Committee for Astronomy and Physics. In August 2014 Dr. Ademar Seabra Da Cruz of Itamaraty has been appointed as the head representative of Brazil in the ICRANet Board. ICRANet is still waiting for the additional nomination of the representatives of the MCTI in the Board and in the Scientific Committee. During 2015, we have:
1) The ICRANet Staff
In the establishment of the ICRANet Scientific Staff we have followed the previously adopted successful strategy:
The purpose of this strategy is to establish strong connections with the most advanced international Research Centers. It also promotes the vital connections between the ICRANet Member Institutions. The Curricula of the ICRANet Staff are given in the Accompanying Document “The ICRANet Staff, Visiting Scientists and Graduate Students at the Pescara Center”:
2) The Collaboration with Brazil (see Enclos. 2)
The collaboration with Brazil has been characterized by a successful program with graduate students, researchers, post-docs, and senior visitor scientists both in Europe and in Brazil (see also point 8 below), including the initiative to establish the ICRANet Brazilian Science Data Center (BSDC). Agreements have been signed between ICRANet and 15 Universities and Research Centers in Brazil (see point 5 below).
3) Inauguration of the Seat in Nice at Villa Ratti, in Yerevan at the National Academy of Sciences and in Brazil at CBPF (see Enclos. 3)
We have completed the restructuring of Villa Ratti for the ICRANet Seat in Nice, also by creating an open lecture space in the park. We been very pleased to receive the invitation by the Municipality of Nice to open ICRANet activities in France, in order to maximize our contacts with other European Countries and more generally with Countries all over the world. We are planning the inauguration in the first semester of 2016. The appeal for the town of Nice and his surroundings, the existence of a modern and efficient airport, the electronic backbones for internet communications are all important elements which add to the decision of the Nice Municipality to offer the historical Villa Ratti as a seat for ICRANet in Nice. Since, an important finding of wall paintings of circa 1750 occurred in the Villa and they have all been restored. The headquarter of the IRAP-PhD program is in Villa Ratti. We were pleased to have, among the first visitors of the opened ICRANet Seat in Villa Ratti, Prof. Roy Kerr, the Nobel Laureate Murray Gell-Mann as well as Prof. Felix Aharonian, Prof. Thibault Damour and Prof. Tom Kibble. We have also started the activities of the ICRANet Seat in Armenia, at the Headquarter of the National Academy of Sciences in Yerevan and at the Byurakan Observatory. The seat agreement has been signed by the Director of ICRANet, Prof. Remo Ruffini, and by the Ambassador of Armenia in Rome, H.E. Sargis Gazharyan, on February 13^{th}, 2015 and has been approved by the Parliament of Armenia and entered in force on November 24^{th}, 2015. We have also started the ICRANet Seat in Rio de Janeiro at CBPF and possibly expanding at the Cassino da Urca.
4) International Meetings (see Enclos. 4)
We have completed the proceedings of:
We have also organized the following meetings:
5) Scientific Agreements (see Enclos. 5)
The following Agreements have been signed, updated and renewed in 2015 by the Director (see Fig. 1):
These collaborations are crucial in order to give ICRANet scientists the possibility to give courses and lectures in the Universities and, vice versa, to provide to the Faculty of such Universities the opportunity to spend research periods in ICRANet institutions.
6) The International Relativistic Astrophysics Ph.D. (IRAP-PhD) program (see Enclos. 6)
One of the major success of ICRANet has been to participate in the International competition of the Erasmus Mundus Ph.D. program and the starting of this program from the 2010 (see Fig. 2). The participating institutions are:
The IRAP PHD program intends to create conditions for high level education in Astrophysics mainly in Europe to create a new generation of leading scientists in the region. No single university in Europe today has the expertise required to attain this ambitious goal by itself. For this reason we have identified universities which offers a very large complementarity expertise. The students admitted and currently following courses and doing research in such a program are given in the following:
Third Cycle 2004-07 - Chiappinelli Anna France - Cianfrani Francesco Italy - Guida Roberto Italy - Rotondo Michael Italy - Vereshchagin Gregory Belarus - Yegoryan Gegham Armenia
Fourth Cycle 2005-08 - Battisti Marco Valerio Italy - Dainotti Maria.Giovanna Italy - Khachatryan Harutyun Armenia - Lecian Orchidea Maria Italy - Pizzi Marco Italy - Pompi Francesca Italy
Fifth Cycle 2006-09 - Caito Letizia Italy - De Barros Gustavo, Brasil - Minazzoli Olivier, Switzerland - Patricelli Barbara, Italy - Rangel Lemos Luis Juracy, Brasil - Rueda Hernandez Jorge Armando Colombia
Sixth Cycle 2007-2010 - Ferroni Valerio Italy - Izzo Luca Italy - Kanaan Chadia Lebanon - Pugliese Daniela Italy - Siutsou Ivan Belarus - Sigismondi Costantino Italy
Seventh Cycle 2008-2011 - Belvedere Riccardo Italy - Ceccobello Chiara Italy - Ferrara Walter Italy - Ferrari Francesca Italy - Han Wenbiao China - Luongo Orlando Italy - Pandolfi Stefania Italy - Taj Safia Pakistan
Eight Cycle 2009-2012 - Boshkayev Kuantay Kazakhstan - Bravetti Alessandro Italy - Ejlli Damian Albanian - Fermani Paolo Italian - Haney Maria German - Menegoni Eloisa Italy - Sahakyan Narek Armenia - Saini Sahil Indian
Ninth Cycle 2010-2013 (including Erasmus Mundus call) - Arguelles Carlos Argentina - Benetti Micol Italy - Muccino Marco Italy - Baranov Andrey Russia - Benedetti Alberto Italian - Dutta Parikshit India - Fleig Philipp Germany - Gruber Christine Austria - Liccardo Vincenzo Italy - Machado De Oliveira Fraga Bernardo Brazil - Martins De Carvalho Sheyse Brazil - Penacchioni Ana Virginia Argentina - Valsan Vineeth India
Tenth Cycle 2011-2014 (including Erasmus Mundus call) -Cáceres Uribe, Diego Leonardo Colombia - Raponi, Andrea Italy - Wang, Yu China - Begue, Damien France - Dereli, Husne Turkey - Gregoris, Daniele Italy - Iyyani, Shabnam Syamsunder India - Pereira, Jonas Pedro Brazil - Pisani, Giovanni Italy - Rakshit, Suvendu India - Sversut Arsioli, Bruno Brazil - Wu, Yuanbin China
Eleventh Cycle 2012-2015 (including Erasmus Mundus call) - Barbarino, Cristina Italy - Bardho, Onelda Albania - Cipolletta, Federico Italy - Dichiara, Simone Italy - Enderli, Maxime France - Filina, Anastasia Russia - Galstyan, Irina Armenia - Gomes De Oliveira, Fernanda Brazil - Khorrami, Zeinab Iran - Ludwig, Hendrik Germany - Sawant, Disha India - Strobel, Eckhard Germany
Twelfth Cycle 2013-2016 (including Erasmus Mundus call and CAPES-ICRANet call) - Ahlén, Olof Sweden - Becerra Bayona, Laura Colombia - Brandt, Carlos Henrique Brazil - Carvalho, Gabriel Brazil - Gómez, Gabriel Colombia - Harutyunyan, Vahagn Armenia - Kovacevic, Milos Serbia - Li, Liang China - Lisakov, Sergey Russia - Maiolino, Tais Brazil - Pereira Lobo, Iarley Brazil - Sridhar, Srivatsan India - Stahl, Clément France - Yang Xiaofeng China
Thirteenth Cycle 2014-2017 (including Erasmus Mundus call and CAPES-ICRANet call) - Aimuratov, Yerlan Kazakhstan - Chang, Yu-Ling Taiwan - Delgado, Camilo Colombia - Efremov, Pavel Ukraine - Gardai Collodel, Lucas Brazil - Karlica, Mile Croatia - Krut, Andreas Germany - Martinez Aviles, Gerardo Mexico - Moradi, Rahim Iran - Otoniel da Silva, Edson Brazil - Silva de Araújo Sadovski, Guilherme Brazil - Ramos Cardoso, Tatiana Brazil - Rodriguez Ruiz, Jose Fernando Colombia
Fourteenth Cycle 2015-2018 - Al-Saud Naiyf Saud Saudi Arabia - Almonacid Guerrero William Alexander Colombia - Gardai Collodel Lucas Brazil/Hungary - Gutierrez Saavedra Julian Steven Colombia - Isidoro dos Santos Júnior Samuel Brazil - Meira Lindolfo Brazil - Melon Fuksman Julio David Argentina - Primorac Daria Croatia - Silva de Araujo Sadovski Guilherme Brazil - Uribe Suárez Juan David Colombia - Vieira Lobato Ronaldo Brazil
We enclose the Posters of the IRAP-PhD for all the above cycles.
7) The Erasmus Mundus Ph.D. program (see Enclos. 7)
Each student admitted to the Erasmus Mundus program of the IRAP Ph.D. is part of a team inside one of the laboratories of the consortium. Each year they have the opportunity to visit the other laboratories of the consortium and enlighten themselves with new topics in the forefront research from world leading experts. In this way the students come in direct contact with some of the leading scientists in the world working in General Relativity, Relativistic Astrophysics and in Quantum Field Theory. In addition to the theoretical centers, we associate experimental and observational centers. This will provide an opportunity to the Ph.D students to obtain a complete education in theoretical relativistic astrophysics and also an experience on how to carry out a specific astrophysical mission. All the institutions participating in IRAP PhD have an extensive experience in international collaborations including visiting professors, post-doctoral researchers and training of Ph.D. students. All of our partners have enrolled Ph.D. students inside their laboratories in various aspects of astrophysics.
8) CAPES-ICRANet Program (see Enclos. 8)
Following the Memorandum of Understanding signed in 2012 with CAPES, we started the CAPES-ICRANet Program on Relativistic Astrophysics and Cosmology to promote the Collaboration between Brazilian and European scientists with five major actions: 1) Fellowships for Brazilian graduate students in the IRAP-PhD program; 2) Senior European scientists visiting Brazil for up to 3 months per year for three years; 3) Senior Brazilian scientists visiting ICRANet seats in Asia and Europe for up to 5 months in a year; 4) Postdoctoral Fellowships for International candidates in ICRANet seats, Scientific Institutions associated to ICRANet, and Institutions with scientists associated to ICRANet, both in Europe and Brazil; 5) Organization of workshops and outreach programs. The first cycle of the program started in September 2013, and on August 30^{th}, 2014 there was the deadline for the call for the second cycle of the program. Since September 18^{th}, 2014, the CAPES-ICRANet program has been suspended. ICRANet has presented the candidatures for the third cycle of the above mentioned five actions, having received all the acceptances from the corresponding host institutions, and is looking for CAPES scrutiny.
9) Project for the ICRANet Center at Cassino da Urca (see Enclos. 9)
We have followed the architectural project for the ICRANet Center at the Cassino da Urca in Rio de Janeiro, Brazil.
10) Lines of research
We turn now to the research activity of ICRANet, which by Statute addresses the developments of research in Astrophysics in the theoretical framework of Albert Einstein’s theories of special and general relativity within the limits of their observational and experimental verifications. Thanks to an unprecedented developments of observational techniques from the ground, from Space, and even in underground experiments in astroparticle physics, we are today capturing astrophysical signals from all over the universe never before conceived and received in human history. The Einstein theory of relativity for many years was relegated to the boundaries of physics, and attracted mainly interest in the mathematics. Since 50 years it has become the authentic conceptual and theoretical “backbone” of the exponentially growing field of relativistic astrophysics in view of the very impressive information and data arriving from all over our universe: in our galaxy, all the way to the farthest objects observed at z = 8 and to the Big bang. There is a very well recognized principle in scientific research that, granted the freedom of thinking and of performing observational or experimental activities, only through the complementary fulfillment of both these aspects, in a collective effort, science progresses. Such a principle is not confined to Relativistic Astrophysics: it generally applies to all scientific activities. In particular, any new idea should be supported by observational and experimental evidence, prior to be presented as a credible alternative to already existing and tested theories. This principle specially applies to the case of Maxwell theory of electrodynamics and Einstein theories of special and general relativity. They have become the best tested theories in science, they are still evolving, and they are at the basis of the technological developments which make possible our daily life. ICRANet considers this principle at the very basis of its activities. In the Reports of previous years, as a testimonial of these developments, I enclosed the paper “The Ergosphere and Dyadosphere of Black Holes” which has appeared in “The Kerr spacetime”, edited by David L. Wiltshire, Matt Visser and Susan M. Scott (Cambridge University Press, 2009). In it, I traced the exciting developments, which started with the understanding on the nuclear evolutions of stars, and had then led to the discovery of neutron stars, and through the work of Riccardo Giacconi and colleagues, to the first identification of a black hole in our galaxy. I also enclosed the paper “Moments with Yakov Borisovich Zeldovich” (appeared in the Proceedings of the International Conference “The Sun, the Stars, the Universe, and General Relativity” in honor of Ya.B. Zel’dovich's 95^{th} Anniversary, Editors R. Ruffini and G.V. Vereshchagin, AIP Conference Proceedings, Vol. 1205 (2010) p. 1-10), recalling some of the crucial moments in the developments of relativistic astrophysics in Soviet Union around the historical figure of Ya.B. Zel’dovich. It is also appropriate to mention that ICRANet organized an International conference in honor of Ya. B. Zel’dovich 100^{th} Anniversary in Minsk (Belaurs) on March 10-14, 2014. I hereby enclose a brochure on the ICRANet activities which has been distributed to all the participants of the MGXIV meeting in Rome in July 2015 (see Enclosure 10). In the previous years Reports I recalled the growth of scientific research from the initial one (see Fig. 3), which was based on three major contributions:
Thanks to a fortunate number of events and conceptual and scientific resonances, a marked evolution of these topics had occurred. From these premises, new fields of research had sprouted up at the ICRANet Center in Pescara, at ICRA in Rome and at the other Member Institutions, especially thanks to the development of the IRAP-PhD program (see point 7 above) and to the many scientists and visitors participating in the ICRANet programs (see Figs. 7, 8, 9a and 9b).
I turn now to a summary of the current activities presented in full details in Volume 2 and Volume 3.
Gamma-rays and Neutrinos from Cosmic Accelerators (Page 1). Particularly important is this report, which summarizes the activities traditionally carried on by the ICRANet Armenian Scientists in the MAGIC and HESS collaborations, which acquire a particular relevance in view of the recent opening of the ICRANet Seat at the National Academy of Science in Armenia. This topic was motivated by Prof. Felix Aharonian joining ICRANet as representative of Armenia in the Scientific Committee and by his appointment as Adjunct Professor of ICRANet on the Benjamin Jegischewitsch Markarjan Chair. Many of the observational work done by Prof. Aharonian are crucial for the theoretical understanding of the ultra high energy sources. Prof. Aharonian started also his collaboration with the IRAP PhD program where he is following the thesis of graduate students as thesis advisor. The evolution and future prospects on the analysis of the high-energy gamma-ray emission are presented in this report by Prof. Aharonian and Dr. Sahakyan. Papers published in 2015 include:
Exact solutions of Einstein and Einstein-Maxwell equations (Page 53) The topic of BKL cosmology is one of the most important and classical contributions of Einstein theory to the study of cosmology, fostered at ICRANet-Pescara by Prof. V. Belinski. This classic work, developed by Belinski, Kalatnikov and Lifshitz, has already been reviewed in all the major treaties on general relativity, but only recently a new insight has come from the impressive discoveries made by Thibault Damour at the IHES in Paris, by Prof. Mark Henneaux at the University of Bruxelles, and by Herman Nicolai at the Albert Einstein Institute in Potsdam, on the way to generalize the BKL theory of cosmological singularity to the string theories. The new results can be of essential importance for understanding the problem of cosmological singularity and of the physics around a black hole, as well as for the identification of hidden internal symmetries in fundamental physics. Prof. Belinski has already finished his part of a new book on “Cosmological singularities” which will be written in co-authorship with Prof. Damour. The book has planned to be published by Cambridge University Press. A shortened and adapted version of this book has already been presented in the AIP conference proceedings of XIV Brazilian School of Cosmology and Gravitation (V. Belinski “On the Singularity Phenomenon in Cosmology”, in: Chapter 2, Cosmology and Gravitation: XIV Brazilian School of Cosmology and Gravitation, Cambridge Scientific Publishers, 2011). Three graduate students of the IRAP PhD program are actually working on this topic for their theses with Profs. Hagen Kleinert and Hermann Nicolai in Berlin. Among the completely new results achieved during the last year, first it should be mentioned the exact description of the quantum dynamics of a supersymmetric version of the Bianchi IX cosmological model and identification the basic role of the Kac-Moody algebra in the structure of the quantum Hamiltonian (T. Damour et al.). The second result is the proof of the existence of the general cosmological solution with the Friedman initial singularity if the influence of the dissipative processes near singularity will be taken into account in the framework of the Israel-Stewart theory (V. Belinski). On a different topic, namely the solitonic equations of GR, an alternative derivation of the Kerr solution had been advanced in a classical paper of 1978 by V. Belinski and V. Zakharov using inverse scattering method. The generalization of this method to the presence of electromagnetic field was constructed in 1980 by G. Alekseev and Kerr-Newman solution has been derived by him in analogous way at the same year. Prof. V. Belinski is now an ICRANet Faculty Member and has further developed this research with the effective collaboration of Prof. G. Alekseev which is an ICRANet Lecturer. During the last years the solitonic solutions of GR has received new interest in respect of the exact solutions of Einstein and Einstein-Maxwell equations: a) The old problem how to generate the exact stationary axisymmetric solutions corresponding to the charged masses with horizons in the framework of Inverse Scattering Method (ISM) was investigated. It was shown that applicability of the ISM in presence of electromagnetic field is not restricted only to the cases with naked singularities (as it has been erroneously stated by some authors). In fact solutions of Einstein-Maxwell equations with horizon also follows from ISM and they are of the same solitonic character. The mathematical procedure of analytical continuations of the naked-singularity solitonic solutions in the space of their parameters which procedure results in solitonic solutions with horizon has been described (G. Alekseev and V. Belinski “Soliton Nature of Equilibrium State of Two Charged Masses in General Relativity”, IJMPCS, 12, 10-18, 2012); b) It was found the new way of derivation of the Kerr solution by adding to the Schwarzchild black hole the solitonic vortex made from the pure gravitational field. With this method, one can figure out how rotational energy can contribute to the mass of the resulting Kerr black hole. Also the relation of the Hanson-Regge type between the mass and angular momentum of a Kerr black hole has been established and its connection with the Christodoulou-Ruffini concept of irreducible mass was analyzed (V. Belinski and H. W. Lee “Kerr rotation as solitonic whirl around Schwarzschild black hole”, Nuovo Cimento, submitted, 2011). During the last year all these constructions was generalized also for the electrically charged black holes. It was shown how one can derive the Kerr-Newman solution by adding a solitonic vortex to the Reissner-Nordstrom black hole. Papers published in 2015 include:
Gamma-Ray Bursts (Page 69) The research on GRBs in ICRANet is wide and has been participated by many Members of the Faculty and of the Adjunct Faculty, as well as by many Lecturers, Research Scientists and graduate students. Traditionally, GRBs are divided into two classes, “short” GRBs and “long” GRBs, arranged in a bimodal distribution with a separation around a duration of 2s. In 2001 we proposed that both short and long GRBs are created by the same process of gravitational collapse to a black hole. The energy source is the e^{+}e^{-} plasma created in the process of the black hole formation. The two parameters characterizing the GRB are the total energy E_{e±}^{tot} of such an e^{+}e^{-} plasma and its baryon loading B defined as B=M_{B}c^{2}/E_{e±}^{tot}, where M_{B} is the mass of the baryon loading. The e^{+}e^{-} plasma evolves as a self-accelerating optically thick fireshell up to when it become transparent, hence we refer to our theoretical model as the “fireshell model”. We have defined a “canonical GRB” light curve with two sharply different components. The first one is the Proper-GRB (P-GRB), which is emitted when the optically thick fireshell becomes transparent and consequently has a very well defined time scale determined by the transparency condition. The second component is the emission due to the collision between the accelerated baryonic matter and the CircumBurst Medium (CBM). This comprises what is usually called the “afterglow”. The relative energetics of the two components is a function of B. For B < 10^{-5} the GRB is “P-GRB dominated”, since the P-GRB is energetically dominant over the second component. The contrary is true for B larger than such a critical value. Since 2001 it has been a major point of our theoretical model that the long GRBs are simply identified with the peak of this second component. In the last years the comprehension of the GRB phenomenon has remarkably increased, thanks to the introduction of the IGC paradigm. The long GRBs associated with Supernovae, which were traditionally considered as an overall single event, are now interpreted as a set of four different Episodes, each one characterized by its own spectral, luminosity and time evolution and corresponding to four different astrophysical processes: -) The “Episode 1” corresponds to the emission from the onset of a Supernova (SN), in a close binary system with a companion neutron star (NS). The initial SN expansion, at non-relativistic velocities, induces a strong matter accretion onto the NS, which reaches the critical mass and then collapses to a black hole (BH). The observed hard X-ray emission is composed of a thermal spectrum plus a power-law component, both evolving in time. -) The “Episode 2”, corresponding to the observations of the GRB, is related to the collapse of the NS into a BH. -) The “Episode 3”, in soft X-rays, occurs when the prompt emission from the GRB fades away and it emerges an additional component we discovered in the Swift XRT data. It has been shown that this component, in energetic (E_{iso} > 10^{52} erg) GRBs-SNe, when referred to the rest-frame of the source, follows a standard behavior of the light curve evolution. This emission encompasses the SN shock break out and the expanding SN ejecta, and gives origin to an authentic “cosmic candle”. -) The “Episode 4” is represented by the observations of the optical emission of the SN, which has been observed in some IGC sources, with redshift z < 0.9. Major progresses have been accomplished this years in the following aspects (see Figs. 10-17):
Papers published in 2015 include:
Relativistic effects in Physics and Astrophysics (Page 237) In this report it is studied the distribution of the GRB bolometric luminosity over the EQTSs, with special attention to the prompt emission phase. We analyze as well the temporal evolution of the EQTS apparent size in the sky. We use the analytic solutions of the equations of motion of the fireshell and the corresponding analytic expressions of the EQTSs which have been presented in recent works and which are valid for both the fully radiative and the adiabatic dynamics. We find the novel result that at the beginning of the prompt emission the most luminous regions of the EQTSs are the ones closest to the line of sight. On the contrary, in the late prompt emission and in the early afterglow phases the most luminous EQTS regions are the ones closest to the boundary of the visible region (see Fig. 18). We find as well an expression for the apparent radius of the EQTS in the sky, valid in both the fully radiative and the adiabatic regimes. Such considerations are essential for the theoretical interpretation of the prompt emission phase of GRBs.
Big data analysis and Cosmology with Astrophysical Transients (Page 307) Particularly interesting, and connected to the above topics, is also the project on big data analysis. The current situation in astrophysics allows to use large archival astrophysical data from infrared, optical and very high energetic radiations. This new situation allows to study a single source in a multi-wavelength context, and permits to obtain more information on the physical mechanisms behind the observed radiation. Recently we have started and developed a program involving the use of already existing software packages for space data reduction, as Swift, Fermi, XMM and HST, and on-ground facilities as optical telescopes at ESO and Canary Island. New collaborations started, about the study of optical transients, as well for the analysis in real-time of high-energy sources as GRBs. Papers published in 2015 include:
Cosmology and Large Scale Structures (Page 323) This topic follows from the extensive work performed at the University of Arizona in Tucson by Prof. Fang LiZhi, and constitutes an important bridge of scientific collaboration with China initiated by Fang. The leading person who is planning to collaborate is Prof. Xiaohui Fan, regent professor at Tucson and representative of Tucson in the ICRANet Steering Committee. We are also capitalizing on the collaboration between Los Alamos National Laboratories (LANL) and Tucson University on High Performance Computing carried on by Chris Fryer, who is adjunct Professor in ICRANet (see Fig. 18b).
Theoretical Astroparticle Physics (Page 327) Astroparticle physics is a new field of research emerging at the intersection of particle physics, astrophysics and cosmology. We focused on several topics with three major directions of research: a) electron-positron plasma, b) thermal emission from relativistic plasma and GRBs, c) neutrinos and large scale structure formation in cosmology, d) self-gravitating systems as Dark Matter in galaxies. Electron-positron plasma appear relevant for GRBs and also for the Early Universe, in laboratory experiments with ultraintense lasers, etc. We study both nonequilibrium effects such as thermalization and associated timescales, as well as dynamical effects such as accelerated expansion in the optically thick regime. Relativistic numerical codes are designed and widely implemented in this research. The basic outcomes include: determination from the first principles of relaxation timescales of optically thick electron-positron plasma with baryonic loading in the wide range of plasma parameters; conclusion that deviations from a simple "frozen radial profile" in spatial distributions of energy and matter densities of expanding electron-positron plasma with baryonic loading are possible. The last conclusion imply in particular the possibility to recover the spatial distribution of matter and energy in the process of collapse of a GRB progenitor to a black hole. We examine quantum corrections to the collision integrals and determine timescales of relaxation towards thermal equilibrium for high temperature electron-positron-photon plasma. (A.G. Aksenov, R. Ruffini. I.A. Siutsou and G.V. Vereshchagin, “Bose enhancement and Pauli blocking in the pair plasma”, in preparation). We study the thermal emission from relativistic plasma and GRBs, which is relevant for understanding GRB emission when plasma in relativistic produces photospheric emission. In particular, we focused on several topics including: transparency of an instantaneously created electron-positron-photon plasma (D. Begue and G.V. Vereshchagin, MNRAS, Vol. 439 (2014) 924); thermal emission in early afterglow from the GRB-SNR interaction (R. Ruffini G. V. Vereshchagin Yu Wang, in preparation), and the traditional topic of photospheric emission in ultrarelativistic outflows (G.V. Vereshchagin, IJMPD 23 (2014) 1430003, and I.A. Siutsou, R. Ruffini and G.V. Vereshchagin, New Astronomy 27 (2014) 30). We also discovered an interesting effect of relativistic spotlight (I.A. Siutsou and G.V. Vereshchagin, PLB 730 (2014) 190). The oral report on this topic will be made by G.V. Vereshchagin. In the framework of cosmology we show how the distribution of Dark Matter (DM) in galaxies can be explained within a model based on a semidegenerate self-gravitating system of fermions in General Relativity. The oral report on this topic will be made by C. Argüelles (see Figs. 19-23). Papers published in 2015 include:
Generalization of the Kerr-Newman solution (Page 595) The unsolved problem of a physical solution in general relativity of an astrophysical object which must be characterized necessarily by four parameters, mass, charge, angular momentum and quadrupole moment, has also been debated for years and it is yet not satisfactorily solved. The presence in ICRANet of Prof. Quevedo as an Adjunct Professor has shown an important result published by Bini, Geralico, Longo, Quevedo [Class. Quant. Grav., 26 (2009), 225006]. This result has been obtained for the special case of a Mashhoon-Quevedo solution characterized only by mass, angular momentum and quadrupole moment. It has been shown that indeed such a Mashhoon-Quevedo solution can be matched to an internal solution solved in the post-Newtonian approximation by Hartle and Thorne for a rotating star. The most important metrics in general relativity is the Kerr-Newman solution which describes the gravitational and electromagnetic fields of a rotating charged mass, characterized by its mass M, charge Q and angular momentum L in geometrical units. This solution characterizes the field of a black hole. For astrophysical purposes, however, it is necessary to take into account the effects due to the moment of inertia of the object. To attack this problem, an exact solution of the Einstein-Maxwell equations have been proposed by Mashhoon and Quevedo which posses an infinite set of gravitational and electromagnetic multipole moments. It is not clear, however, how this external solution to an astrophysical object can be matched to a physical internal solution corresponding to a physically acceptable rotating mass. Are here reported current progresses in using an explicit solution of the Hartle-Thorne equation to an eternal solution with N independent quadrupole moments. Equally important has been the result recently obtained by Belvedere showing that a fast rotating model of neutron star with global charge neutrality within the Hartle-Thorne approximation leads to an internal solution of the Kerr metric. Papers published in 2015 include:
Black Holes and Quasars (Page 693) This report refers to the activity of Prof. Brian Punsly, who is actively participating within ICRANet with the publication of his internationally recognized book on “Black hole gravitohydromagnetics”, the first and second edition (2010) being published with Springer. In addition, Prof. Punsly have been interested in observational properties of quasars such as broad line emission excess in radio loud quasars accentuated for polar line of sight and excess narrow line widths of broad emission lines in broad absorption line quasars, showing that this is best explained by polar lines of sight. Papers published in 2015 include:
Cosmology group of Tartu Observatory (Page 699) Prof. Einasto has been collaborating in the previous years intensively within ICRANet about the large scale structure of the Universe and its possible fractal structure. With Prof. Einasto there is also the collaboration of Prof. G. Hutsi. Prof. Einasto is an Adjunct Professor of ICRANet and an active member of the Faculty of the IRAP PhD. Prof. Einasto has completed a book reviewing the status of the dark matter and the large scale structure of the universe published by World Scientific as Volume 14^{th} in the Advanced Series in Astrophysics and Cosmology Series edited by L.Z. Fang and R. Ruffini. This book covers the material of the lectures delivered in the IRAP PhD program as well as an historical perspective between the different approaches to the study of the dark matter content of the universe in the west and in the former Soviet union. Papers published in 2015 include:
The electron-positron pairs in physics and astrophysics (Page 705) This problem “The electron-positron pairs in physics and astrophysics: from heavy nuclei to black holes” has been the subject of a physics reports of more than 500 references, which is inserted on page 929, by Ruffini, Vereshchagin and Xue. There, all the different aspects of the field has been reviewed: The fundamental contributions to the electron-positron pair creation and annihilation and the concept of critical electric field; Nonlinear electrodynamics and rate of pair creation; Pair production and annihilation in QED; Semi-classical description of pair production in a general electric field; Phenomenology of electron-positron pair creation and annihilation; The extraction of blackholic energy from a black hole by vacuum polarization processes; Plasma oscillations in electric fields; Thermalization of the mildly relativistic pair plasma. Due to the interaction of physics and astrophysics we are witnessing in these years a splendid synthesis of theoretical, experimental and observational results originating from three fundamental physical processes. They were originally proposed by Dirac, by Breit and Wheeler and by Sauter, Heisenberg, Euler and Schwinger. For almost seventy years they have all three been followed by a continued effort of experimental verification on Earth-based experiments. The Dirac process, e^{+}e^{-} →2 g, has been by far the most successful. It has obtained extremely accurate experimental verification and has led as well to an enormous number of new physics in possibly one of the most fruitful experimental avenues by introduction of storage rings in Frascati and followed by the largest accelerators worldwide: DESY, SLAC etc. The Breit-Wheeler process, 2g → e^{+}e^{-}, although conceptually simple, being the inverse process of the Dirac one, has been by far one of the most difficult to be verified experimentally. Only recently, through the technology based on free electron X-ray laser and its numerous applications in Earth-based experiments, some first indications of its possible verification have been reached. The vacuum polarization process in strong electromagnetic field, pioneered by Sauter, Heisenberg, Euler and Schwinger, introduced the concept of critical electric field. It has been searched without success for more than forty years by heavy-ion collisions in many of the leading particle accelerators worldwide. In view of the recent developments in the free electron lasers, we have invited at ICRANet Prof. John Madey, the inventor of the free electron lasers, to give a set of lectures and to explore the possibility to have, by focusing the free electron laser signals, the realization in the laboratory of the Breit-Wheeler process. Prof. Madey has also accepted the position of Adjunct Professor at ICRANet, and he is planning a collaboration with us in the forthcoming years. In this report, using the formula obtained for the rate of pair production in spatially varying external electric field dynamical equations describing the space and time evolutions of pair-induced electric charges, currents and fields bounded within a given spatial region are solved. We also study nonlinear electrodynamics by considering two laser beams collision and laser beam colliding with high-energy photon and neutrino beam, and scaling behaves of strong QED, as well as quantum corrections to black hole properties due to Euler-Heisenberg Lagrangian, gravitational and electric energies conversion in gravitational collapses. The origin of fermion mass is due to quantum gravity. These results imply the wave propagation of the pair-induced electric field and wave-transportation of the electromagnetic energy in the strong field region. Analogously to the electromagnetic radiation emitted from an alternating electric current, the space and time variations of pair-induced electric currents and charges emit an electromagnetic radiation. We show that this radiation has a peculiar energy-spectrum that is clearly distinguishable from the energy-spectra of the bremsstrahlung radiation, electron–positron annihilation and other possible background events. This possibly provides a distinctive way to detect the radiation signatures for the production and oscillation of electron–positron pairs in ultra-strong electric fields that can be realized in either ground laboratories or astrophysical environments. (W.-B. Han, R. Ruffini, S.-S. Xue, Physics Letters B 691 (2010) 99). We focus our attention on studying how this oscillation frequency approaches the plasma frequency. The spectrum of this dipole radiation shows a unique line-like feature, as discussed above. This can possibly be candidate of the recently discovered 3.6 eV emission line from Galactic centers. The e^{+}e^{−} pairs generated by the vacuum polarization process around a gravitationally collapsing charged core are entangled in the electromagnetic field (R. Ruffini, L. Vitagliano, S.-S. Xue, Phys. Lett. B 573, (2003) 33), and thermalize in an electron–positron–photon plasma on a time scale ~ 10^{4} _{C} (R. Ruffini, L. Vitagliano, S.-S. Xue, Phys. Lett. B 559, (2003) 12). As soon as the thermalization has occurred, the hydrodynamic expansion of this electrically neutral plasma starts (R. Ruffini, J. Salmonson, J. Wilson, S.-S. Xue, A&A Vol. 335 (1999) 334; Vol. 359 (2000) 855). While the temporal evolution of the e^{+}e^{−} gravitationally collapsing core moves inwards, giving rise to a further amplified supercritical field, which in turn generates a larger amount of e^{+}e^{−} pairs leading to a yet higher temperature in the newly formed e^{+}e^{−} plasma. We study this theoretically challenging process, which is marked by distinctive and precise quantum and general relativistic effects, and follow the dynamical phase of the formation of Dyadosphere and of the asymptotic approach to the horizon by examining the time varying process at the surface of the gravitationally collapsing core. We conclude that the core is not discharged or, in other words, the electric charge of the core is stable against vacuum polarization and electric field is amplified during the gravitational collapse. As a consequence, an enormous amount of pairs is left behind the collapsing core and a Dyadosphere (G. Preparata, R. Ruffini, S.-S. Xue, A&A Vol. 338 (1998) L87) is formed. Recently, we study this pair-production process in a neutral collapsing stellar core at or over nuclear densities, and show an overcritical electric field on the surface of baryon core. It is shown that in gravitational core-collapse, such an electric field dynamically evolves in the space-time and electron-positron pairs are produced, leading to the Dyadosphere of electron-positron pairs. This result has been published in W. B. Han, R. Ruffini, S.-S. Xue, Physics Review D86, 084004 (2012). In order to understand the back-reaction of such electric energy building and radiating on collapse, we further adopt a simplified model describing the collapse of a spherically thin capacitor to give an analytical description how gravitational energy is converted to both kinetic and electric energies in collapse. It is shown that (i) averaged kinetic and electric energies are the same order, about a half of gravitational energy of spherically thin capacitor in collapse; (ii) caused by radiating and rebuilding electric energy, gravitational collapse undergoes a sequence of ``on and off'' hopping steps in the microscopic Compton scale. This has been published (R. Ruffini, and S-S. Xue, Physics Letters A377 (2013) 2450). Taking into account the Euler-Heisenberg effective Lagrangian of one-loop nonperturbative QED contributions, we formulate the Einstein-Euler-Heisenberg theory and study the solutions of nonrotating black holes with electric and magnetic charges in spherical geometry. In the limit of strong and weak electromagnetic fields of black holes, we calculate the black hole horizon radius, area, and total energy up to the leading order of QED corrections and discuss the black hole irreducible mass, entropy, and maximally extractable energy as well as the Christodoulou-Ruffini mass formula. This result has been published (R. Ruffini, Y.-B. Wu and S.-S. Xue, Physics Review D88, 085004 (2013)). An interesting aspect of effective field theories in the strong-field limit has recently been emphasized in a completely different class of quantum field theories. These have the property of developing in the strong-field limit an anomalous power behavior. We study that pair-production in super-position of static and plane wave fields, and in the strong fields expansion, the leading order behavior of the Euler-Heisenberg effective Lagrangian is logarithmic, and can be formulated as a power law. These results have been published in (H. Kleinert, E. Strobel and S-S. Xue, Phys. Rev. D88, 025049 (2013), Annals of Physics Vol. 333 (2013) 104). On the ground laboratories, experiments, for example ELI, set up for intense laser beams and their collisions with high energy photons (Wheeler process) has been going on very fast to study the strong field phenomena in particular electron-positron pair production. We have investigated the fundamental processes relevant to the issues of intense laser physics, pair-production in multi-component electric fields (Nucl. Phys B 886, (2014) 1153); two laser beams colliding with a high-energy photon (Y.-B. Wu and S-S. Xue, Phys. Rev. D 90, 013009 (2014))，as well as pair-oscillation leading to electromagnetic and gravitational radiation (W.-B. Han and S.-S. Xue, Phys. Rev. D89 (2014) 024008). We study the photon circular-polarization produced by two-laser beams collision (R. Mohammadi, I. Motie, and S.-S. Xue, Phys. Rev. A 89, 062111 (2014)), and by laser and neutrino beams collisions (Phys. Lett. B 731 (2014) 272; Phys. Rev. D 90, 091301(R) (2014)). These fundamental processes are also relevant to high-energy phenomena in relativistic astrophysics, that we will study further. Papers published in 2015 include:
From nuclei to compact stars (Page 1271) A multi-year study in ICRA and ICRANet has been devoted to the relativistic Thomas-Fermi equations. The early work was directed to the analysis of superheavy nuclei. In the last years, a special attention has been given to formulate a unified approach which, on one side, describes the superheavy nuclei and, on the other, what we have called “Massive Nuclear Cores”. These last ones are systems of about 10^{57} nucleons, kept together in beta equilibrium and at nuclear density due to the effect of self gravity. The most surprising result has been that the analytic treatment used by Prof. Popov and his group in their classical work on superheavy nuclei can be scaled to the Massive Nuclear Core regime in presence of gravity. The consequences of this is that an electric field close to the critical value E_{c} = m_{e}^{2}c^{3}/(eℏ) can be found on the surface layer of such Massive Nuclear Cores. This fortunate result has triggered a great interest and has opened what it can be considered a new approach to the electrodynamics of neutron stars within ICRANet. This activity comprises the study of compact objects such as white dwarfs, neutron stars and black holes. It requires the interplay between nuclear and atomic physics together with relativistic field theories, e.g., general relativity, quantum electrodynamics, quantum chromo-dynamics, as well as particle physics. In addition to the theoretical physics aspects, the study of astrophysical scenarios characterized by the presence of a compact object has also started to be focus of extensive research within this group. The research is divided into the following topics: nuclear and atomic astrophysics; white dwarfs and neutron star physics and astrophysics; radiation mechanisms in white dwarfs and neutron stars; exact solutions of the Einstein and Einstein-Maxwell equations in astrophysics and critical fields and non-linear electrodynamics effects in astrophysics. The research activity sees the collaboration within ICRANet of D. Arnett, D. Bini, L. Izzo, H. Kleinert, V. Popov, J. Rueda, R. Ruffini, G. Vereschagin, and S.-S. Xue; external collaborations with K. Boshkayev, C. Cherubini, S. Chiapparini, S. B., S. Filippi, C. L. Fryer, E. Gacía-Berro, P. Lorén Aguilar, S. O. Kepler, B. Kulebi, M. Malheiro, R. M. Jr. Marinho, G. Mathews, D. P. Menezes, H. Mosquera-Cuesta, R. Negreiros, L. Pachón, H. Quevedo, C. Valenzuela, and C. A. Z. Vasconcellos; and includes as well the participation of postdocs; R. Belvedere, R. Camargo, J. G. Coelho, and S. M. de Carvalho, and graduate students from the IRAP PhD, the Erasmus Mundus Joint Doctorate, and the CAPES-ICRANet Programs; L. Becerra, D. L. Cáceres, F. Cipolletta, M. Muccino, F. G. Oliveira, J. Pereira, and Y. Wu. One of the main objectives have been to construct a unified approach for nuclei, superheavy nuclei up to atomic numbers of the order of 10^{5}–10^{6}, and what we have denominated “nuclear matter cores of stellar dimensions”: characterized by atomic number of the order of 10^{57}; composed by a degenerate fluid of neutrons, protons and electrons in beta-equilibrium; globally neutral configurations; expected to be kept at nuclear density by self-gravity. The study of these objects going from the microscopic to the macroscopic is at the base of the theory of white dwarfs, neutron stars, hyperon stars, strange quark stars, and other related compact objects. The analysis of superheavy nuclei has historically represented a major field of research, developed by Prof. V. Popov and Prof. W. Greiner and their schools. In 2007 the ICRANet group found the welcome result that all the analytic work developed by Prof. V. Popov and the Russian school can be applied using scaling laws satisfied by the relativistic Thomas-Fermi equation to the case of nuclear matter cores of stellar dimensions, if the beta equilibrium condition is properly taken into account. Since then, a large variety of problems has emerged, which have seen the direct participation of the above mentioned ICRANet Faculty and Adjunct Faculty staff. The analysis of globally neutral and compressed configurations composed by a nucleus made of relativistic degenerate neutrons and protons surrounded by relativistic degenerate electrons in beta-equilibrium was accomplished in 2011 by Rotondo et al. generalizing the Feynman-Metropolis-Teller treatment of compressed atoms to relativistic regimes. This treatment led to the possibility of studying the degenerate compressed matter in white dwarfs, and to compute the star’s structure within a fully self-consistent relativistic framework. The generalization of the general relativistic theory of white dwarfs to the rotating case has been successfully achieved in the thesis work of K. Boshkayev. The entire family of uniformly rotating stable white dwarfs has been already obtained by studying the mass-shedding, the inverse beta-decay, pycnonuclear, and axisymmetric instabilities. The maximum mass and the minimum (maximum) rotation period (frequency) have been obtained for selected nuclear compositions. These results are relevant both for the theory of type Ia supernovae as well as for the recent work of M. Malheiro, J. Rueda and R. Ruffini on the description of Soft-Gamma-Ray Repeaters (SGRs) and Anomalous X-Ray Pulsars (AXPs) as rotation powered white dwarfs, following a pioneer idea of M. Morini et al. (1988) and of B. Paczynski (1990) on the AXP 1E 2259+586. The recent observation of SGR 0418+5729 promises to be an authentic Rosetta Stone, a powerful discriminant for alternative models of SGRs and AXPs. The loss of rotational energy of a neutron star cannot explain the X-ray luminosity of SGR 0418+5729, excluding the possibility of identifying this source as an ordinary spin-down powered neutron star. The inferred upper limit of the surface magnetic field of SGR 0418+5729 B < 7.5x10^{12} G, describing it as a neutron star within the magnetic braking scenario, is well below the critical magnetic field B_{c}=2m^{2}_{e}c^{3}/(he) =4.4x10^{13} G, challenging the power mechanism based on magnetic field decay purported in the magnetar scenario. We have shown that the observed upper limit on the spin-down rate of SGR 0418+5729 is, instead, perfectly in line with a model based on a massive fast rotating highly magnetized white dwarf of fiducial mass M=1.4M_{Sun}, radius R=10^{3} km, and moment of inertia I =10^{49} g cm^{2}. We have analyzed the energetics of all SGRs and AXPs including their steady emission, the glitches and their subsequent outburst activities. It can be then shown that the occurrence of the glitch, the associated sudden shortening of the period, as well as the corresponding gain of rotational energy, can be explained by the release of gravitational energy associated to a sudden contraction and decrease of the moment of inertia of the white dwarfs, consistent with the conservation of their angular momentum. The energetics of the steady emission as well as the one of the outbursts following the glitch can be simply explained in term of the loss of the rotational energy in view of the moment of inertia of the white dwarfs, much larger than the one of neutron stars. There is no need here to invoke the decay of ultra-strong magnetic fields of the magnetar model (see Fig. 24). A more exhaustive analysis of SGR 0418+5729 within the white dwarf model has been recently achieved in the Ph. D. thesis of K. Boshkayev. The request of the rotational stability of the white dwarf gives bounds for the mass, radius, moment of inertia and magnetic field, through the analysis of constant rotation period sequences of uniformly rotating white dwarfs. We have also analyzed the emission properties in the optical band, and inferred the cyclotron frequencies associated to their magnetic fields which might cause absorption features in the optical wavelengths. The same analysis has been accomplished for Swift J1822.3-1606 and 1E 2259+586. We are in addition considering the possible progenitors of these massive fast rotating highly magnetized white dwarfs. We have considered the possibility that white dwarfs mergers could be the progenitor of white dwarfs with the above desirable properties, hence of SGRs and AXPs. In collaboration with P. Loren from University of Exeter in UK, and the group led by Prof. Garcia-Berro at Universitat Politecnica de Catalunya and Institute for Space Studies of Catalonia in Barcelona, we have performed numerical simulations of white dwarf mergers. We have shown that the products of these mergers consist of a hot central magnetized white dwarf surrounded by a heavy rapidly rotating disk. The evolution of the post-merger massive rapidly rotating magnetized white dwarf and its emission properties in the optical bands, have been computed. We have shown that these properties are consistent with AXPs such as 4U 0142+61, which show an infrared excess explainable via the existence of a dust disk, whereas the surface black body emission well describes the observations in the UV bands. The emission by these white dwarfs in the X-ray band is currently under consideration and it is the subject of the Ph. D. thesis of D. L. Cáceres, and part of the research project of the Postdoc J. G. Coelho. A further extension of the above treatment of white dwarfs to the case of finite temperatures has been part of the PhD work of S. M. de Carvalho. The inclusion of finite temperature effects is relevant in view of the recent discovery of ultra-low mass white dwarfs with masses. 0.2M_{Sun}, which are companion of neutron stars in relativistic binaries (Antoniadis et al., 2012, 2013). These low-mass white dwarfs represent the perfect arena for testing the equation of state of compressed matter since the central densities of these objects are of the order of 10^{6} g cm^{-3}, where the degenerate approximation breaks down, thus thermal effects cannot be neglected. We have used this new equation of state to construct the mass-radius relation of white dwarfs at finite temperatures in a wide range of central densities. We analyze the particular case of the white dwarf companion of the pulsar PSR J1738+0333, which is expected to have a mass 0.18M_{Sun} (Antoniadis et al., 2012). Using the observed surface effective temperature and surface gravity of the white dwarf we have inferred the central temperature in the white dwarf core. Regarding the structure properties of white dwarfs, it has been recently purported by Das & Mukhopadhyay (2013) that the presence of huge uniform magnetic fields of the order of 10^{18} G, in the interior of a white dwarf, increases its maximum mass from the traditional Chandrasekhar value, 1.44 M_{Sun}, to a new upper bound, 2.58 M_{Sun}. Such a much larger limit would make these astrophysical objects viable candidates for the explanation of the superluminous population of type Ia supernovae. We have shown in (Coelho et al., 2014) that the new mass limit was obtained neglecting several macro and micro physical aspects such as gravitational, dynamical stability, breaking of spherical symmetry, general relativity, inverse b decay, and pycnonuclear fusion reactions. These effects are relevant for the self-consistent description of the structure and assessment of stability of these objects. When accounted for, they lead to the conclusion that the existence of such ultra-magnetized white dwarfs in nature is very unlikely due to violation of minimal requests of stability, and therefore the canonical Chandrasekhar mass limit of white dwarfs has to be still applied. Progress has been also made in a formulation of the equations of equilibrium of neutron stars. We studied the construction of neutron stars within a fully consistent formulation equilibrium configurations in general relativity accounting for all the fundamental interactions. These neutron stars fulfill global but not local charge neutrality. The full system of equilibrium equations formed a coupled system that we have denominated Einstein-Maxwell-Thomas-Fermi (EMTF) equations. The solution of these new equilibrium equations leads to a markedly different mass-radius relation of neutron stars due to the different treatment of the boundary-value problem imposed by the core-crust transition. A crust of smaller mass and thickness is obtained (see Fig. 25). This work has been successfully generalized to the case of uniformly rotating neutron stars, and it has been part of the Ph. D. thesis of R. Belvedere, current Postdoc at ICRANet-Rio. The stability of neutron stars against mass-shedding and secular axisymmetric instabilities have been addressed. The analysis of the properties of the core-crust interface of a neutron star, such as its surface and Coulomb energies, and stability against perturbations have been studied by Y. Wu and J. Pereira in their Ph. D. theses. This entire program has been developed in order to identify the initial boundary conditions for the electrodynamical process occurring at the onset of gravitational collapse leading to a black hole. We have recently investigated in collaboration with Prof. C. A. Z. Vasconcellos and other Brazilian colleagues, extensions of the traditional sigma-omega-rho relativistic nuclear mean field model applied to the nuclear matter in neutron stars. We have introduced many-body correlations within a quantum hadrodynamics (QHD) model with parameterized couplings. We considered the whole fundamental baryon octet and the many-body forces are simulated by nonlinear self-couplings and meson-meson interaction terms involving scalar-isoscalar, vector-isoscalar, vector-isovector, and scalar-isovector. Coming back to globally versus locally neutral neutron stars, there is the need of seeking for potential observations which could reveal the aforementioned new structure of the neutron star. Since the thermal evolution of a neutron star is strongly sensitive to its microscopic and macroscopic properties, one possibility to unveil the neutron star structure is represented by observing their cooling-down. Thus, we have recently computed in collaboration with S. M. de Carvalho, current Postdoc in University of Fluminense and ICRANet-Rio, and Prof. R. Negreiros from the University of Fluminense, the cooling curves of locally and globally neutral neutron stars. We have integrated numerically the energy balance and transport equations in general relativity, for globally neutral neutron stars with crusts of different masses and sizes, according to this theory for different core-crust transition interfaces. In the simulation we consider all the main radiation emissivities, heat capacity, thermal conductivity, and possible superconductivity of the nucleons. We found that the relaxation time depends upon the density at the base of the crust and, therefore, accurate observations of the thermal relaxation phase in the first years of evolution of newly-born neutron stars might give crucial information on the core-crust transition, probing the inner composition and structure of these objects. Turning to neutron star astrophysics, we have also analyzed an interesting class of pulsars referred to as high-magnetic field pulsars, which are thought to be transition objects between pulsars and magnetars. The reason for this is that using fiducial values of mass M=1.4M_{Sun}, radius R=10 km, and moment of inertia I =10^{45} g cm^{2 }for a neutron star, the magnetic fields inferred using the traditional magneto-dipole rotating model of pulsars appear to be very close and some of them even higher than the critical field of quantum electrodynamics, B_{c}=2m^{2}_{e}c^{3}/(he) =4.4x10^{13} G. In addition, their X-ray luminosities appear higher than the rotational energy loss of the object, avoiding their explanation as rotation-powered pulsars. However, we have recently shown in R. Belvedere, J.A. Rueda, R. Ruffini, ApJ, 799, 23 (2015) that the use of realistic parameters of rotating neutron stars obtained from numerical integration of the self-consistent axisymmetric general relativistic equations of equilibrium with realistic interior equation of state leads to values of the magnetic field and radiation efficiency of pulsars very different from estimates based on fiducial parameters. Furthermore, we compared and contrasted the magnetic field inferred from the traditional Newtonian rotating magnetic dipole model with respect to the one obtained from its general relativistic analog which takes into due account the effect of the finite size of the source. We have indeed shown that all the high-magnetic field pulsars can be described as canonical rotation-powered objects driven by the rotational energy of the neutron star, and with magnetic fields lower than the quantum critical field for any value of the neutron star mass (see Fig. 26). The understanding of the theory of neutron stars has allowed the analysis of their role in astrophysical systems such as the GRBs, the GRB-Supernova, and the short GRBs. It has been analyzed in detail the binary progenitors of these systems with particular emphasis on the role played by neutron stars. Concerning the role of neutron stars in the induced gravitational collapse (IGC) paradigm of gamma-ray bursts (GRBs) associated with supernovae (SNe) Ic. The progenitor of those sources is a tight binary system composed of a carbon-oxygen (CO) core and a neutron star (NS) companion. The explosion of the SN leads to hypercritical accretion onto the NS companion, which reaches the critical mass, hence inducing its gravitational collapse to a black hole (BH) with consequent emission of the GRB. The first estimates of this process by Rueda and Ruffini (2012) were based on a simplified model of the binary parameters and the Bondi-Hoyle-Lyttleton accretion rate. We present new results in (Fryer et al., 2014) with the first full numerical simulations of the IGC phenomenon. We simulate the core-collapse and SN explosion of CO stars to obtain the density and ejection velocity of the SN ejecta. We follow the hydrodynamic evolution of the accreting material falling into the Bondi-Hoyle surface of the NS all the way up to its incorporation in the NS surface. The simulations go up to BH formation when the NS reaches the critical mass. For appropriate binary parameters, the IGC occurs in short timescales 10^{2}–10^{3} s owing to the combined effective action of the photon trapping and the neutrino cooling near the NS surface (see Fig. 27). We also show that the IGC scenario leads to a natural explanation for why GRBs are associated only with SNe Ic with totally absent or very little helium. Concerning short GRBs, we had the first example that they are the result of the merger of neutron star binaries. F. Gomes Oliveira, as part of her Ph. D. thesis, has computed the evolution of binary neutron stars up to the merger point to evaluate the emission of gravitational waves in these systems. The dynamics has been simulated via the effective one-body formalism of Prof. Thibault Damour, up to fourth post-Newtonian order. The detectability of this emission by second generation detectors such as Advanced LIGO has been assessed, and the total energy output in gravitational waves has been compared with the observed emission in both X and gamma rays. This work has been possible thanks to the analysis of the first genuinely short GRB 090227B by Muccino et al. (2013), where it has been shown that the properties of this GRB indeed are consistent with a binary neutron star progenitor. Some of the above topics are leading to the preparation of a new book with Springer with the title “From the nuclei to the stars” by J. Rueda and R. Ruffini. Papers published in 2015 include:
Supernovae (Page 1375) GRBs have broaden the existing problematic of the study of Supernovae. In some models, e.g. the “collapsar” one, all GRBs are assumed to originate from supernovae. Within our approach, we assume that core-collapse supernovae can only lead to neutron stars, and we also assume that GRBs are exclusively generated in the collapse to a black hole. Within this framework, supernovae and GRBs do necessarily originate in a binary system composed by an evolved main sequence star and a neutron star. The concept of induced gravitational collapse leads to the temporal coincidence between the transition from the neutron star to the black hole and the concurrent transition of the late evolved star into a supernova. This very wide topic has been promoted by the collaboration with Prof. Massimo Della Valle, who is an Adjunct Professor at ICRANet and who is currently Co-PI of a VLT proposal “A spectroscopic study of the supernova/GRB connection”. This kind of research is particularly important for trying to find a coincidence between electromagnetic radiation, high-energy particles, ultra high-energy cosmic rays, neutrinos and gravitational radiation, possible observable for existing or future detectors. A short summary of the internationally well-known activities of Prof. Della Valle, who is an Adjunct Professor at ICRANet, is given in the report, which contains the many publications in international journals. Prof. Della Valle is also very actively following one graduate student of the IRAP PhD program. A new stimulus has come from the recent understanding of the IGC paradigm, which allows a completely new understanding of the relation between the supernovae and the GRBs. Papers published in 2015 include:
Symmetries in General Relativity (Page 1387) This topic has been developed as an intense collaboration between various research groups. We had and we have the opportunity of the presence in Pescara of Prof. Roy Kerr as ICRANet Adjunct Professor and discussed the fundamental issues of the uniqueness of the Kerr-Newman Black Hole. A distinct progress in this collaboration has appeared in the paper by D. Bini, A. Geralico, R. Kerr, “The Kerr-Shild ansatz revised”, International Journal of Geometric Methods in Modern Physics (IJGMMP) 7 (2010), 693-703. Profs. R.T. Jantzen, L. Stella (Observatory of Monte Porzio, Rome), O. Semerak (Czech Republic), D. Bini and Dr. A. Geralico have studied the problem of motion of test particles in black hole spacetimes, in presence of a superposed radiation field. The scattering of radiation by the test particles causes a friction-like drag force which forces particles on certain equilibrium orbits outside the black hole horizon. This interesting effect, known as Poynting-Robertson effect, has been deeply investigated in many different contexts: besides the Schwarzschild and Kerr black hole, novel results have been published for the case of a Vaidya radiation metric. In the latter case, in fact, one takes the advantages of having an exact solution of the Einstein’s field equations whose source is a null field. Among the various consequences we mention that while a unique equilibrium circular orbit exists if the photon flux has zero angular momentum, multiple such orbits appear if the photon angular momentum is sufficiently high. Furthermore other solutions of the Weyl class with cylindrical symmetry as well as solutions within the class of exact gravitational plane waves and electromagnetic plane waves have been examined in the context of Poynting-Robertson like effects obtaining a number of physically relevant situations. Bini and Geralico have also considered the motion of spinning test particles in Kerr spacetime in full generality with the aim to study deviations between the world lines of spinning objects in comparison with those of geodesic test particles, generalizing some recent works on the same topic where motion were but constrained on the equatorial plane. Bini, Geralico and Jantzen have been able to obtain new foliations in spacetimes admitting separable geodesics. These “separable geodesic action slicing” have been used then to explore certain geometrical properties of horizon penetrating coordinates in black hole spacetimes. Other collaborations, again for what concerns the topics included in symmetries in General Relativity, have been started with Profs. A. Ortolan (INFN Legnaro, Padova, Italy) and P. Fortini (University of Ferrara, Italy) to study of the interaction of electromagnetic waves with gravitational waves, with the gravitational waves considered in the exact theory and not in its linear approximation. Papers published in 2015 include:
Self Gravitating Systems, Galactic Structures and Galactic Dynamics (Page 1507) In collaboration with Campus Bio-Medico in Rome there are ongoing researches on galactic structures. The Reports is focused on analytical and numerical methods for the study of classical self-gravitating fluid/gaseous masses. A series of papers of this group have been devoted in the past to the generalization of the classical theory of ellipsoidal figures of equilibrium using virial methods. The research activities of the group have focused subsequently on functional methods for obtaining equilibrium solutions for polytropic self-gravitating systems that rotate and have a non uniform vorticity. The group has recently published a novel and important result in the context of analogous geometry theory. It is well known that the wave equation for the perturbations of given a perfect barotropic and irrotational Newtonian fluid can be rewritten as an “effective General Relativity”. They have extended this result including the possibility for the fluid to be self-gravitating. This work opens the path for a new interpretation of classical white-dwarf theory in terms of curved space-time techniques. The group has also studied the perturbations of classical compressible rotating but not gravitating fluids as occurring in generalized acoustic black holes. It has also analyzed the Analog Gravity formalism at full nonlinear level through Von Mises’ Wave Equation for irrotational configurations. Papers published in 2015 include:
Interdisciplinary Complex Systems (Page 1545) We recall the successful attempt of applying methodologies developed in Relativistic Astrophysics and Theoretical Physics to researches in the medicine domain. The Report adopts analytical and numerical methods for the study of problems of nonlinear dynamics focusing on biological systems and using a theoretical physics approach. It is well established both numerically and experimentally that nonlinear systems involving diffusion, chemotaxis, and/or convection mechanisms can generate complicated time-dependent spiral waves, as in happens in chemical reactions, slime molds, brain and in the heart. Because this phenomenon is global in Nature and arises also in astrophysics with spiral galaxies, the goal of this research activity has been to clarify the role of this universal spiraling pattern. The group has studied numerically the nonlinear partial differential equations of the theory (Reaction-Diffusion) using finite element methods. The group has recently published moreover a novel and important result: an electromechanical model of cardiac tissue, on which spiral moves and causes the domain to deform in space and time (see Fig. 28). This model is a real breakthrough in the context of theoretical biophysics, leading to new scenarios in the context of computational cardiology. In 2015 the group has focused its research on classical hydrodynamics, evaluating the stress exerted by the fluid on the domain walls and introducing an indicator of risk for their damage. Such a methodology, named as “three-band decomposition analysis of wall shear stress in pulsatile flows”, has been immediately applied to hemodynamical problems which have been numerically integrated (see Fig. 29), but results promising also for other problems of physical and biological sciences and for engineering. Papers published in 2015 include:
An important fundamental research topic is the investigation of “analogue models of gravity”. Such models have been used to understand many aspect of gravitational phenomena, in particular the mechanism of Hawking- and Unruh-Radiation, by studying in supersonic flow nozzles. These were of great help in dispersing criticism of these radiations based on our ignorance of the divergences of local quantum field theory at ultrashort distances. Another important analogy is bases on the relation between Einstein-Cartan Physics and the theory of defects in solids, worked out in detail in the textbook by our adjunct faculty members H. Kleinert: <http://users.physik.fu-berlin.de/~kleinert/kleinert/?p=booklist&details=1>. This analogy has recently allowed to understand the equivalence of Einstein's theory of gravitation with his Teleparallel Theory of Gravitation as a result of a novel gauge symmetry. The first uses only the curvature of spacetime to explain gravitational forces, while the second uses only torsion. The equivalence relies on the fact that crystalline defects of rotation and translation (disclinations and dislocations, respectively) are not independent of each other, but the ones can be understood as superpositions of the other. Moreover, the analogy has allowed to set up an infinite family of intermediate theories in which curvature and torsion appear both <http://klnrt.de/385/385.pdf>. Finally, all geometries relevant in gravitational physics has been derived from a completely new theory of multivalued fields <http://www.physik.fu-berlin.de/~kleinert/kleinert/?p=booklist&details=9>.
The volume: Einstein, Fermi and Heisenberg, and the birth of relativistic astrophysics is being completed by R. Ruffini with contributions by Emanuele Alesci, Donato Bini, Dino Boccaletti, Andrea Geralico, and Robert T. Jantzen. This book has some different goals: 1) to translate into English a set of papers by Fermi which were available only in Italian; 2) to try to understand the reason why, having been one of the greatest experts on Einstein theory in the earliest years of his life, after his transfer to Rome and later on to the United States Fermi never published anything on Einstein theory: the only paper by Fermi treating general relativity and cosmology was written to prove George Gamow wrong and Einstein theory not proper to the analysis of cosmology – on the contrary, the work of Fermi turned out to be the real starting point of modern relativistic cosmology and proved the validity of Gamow theory and of course of the Einstein theory of general relativity; 3) the book also endures on the difficult dialogue between Einstein and Heisenberg, with some personal reminiscence, and illustrates how all the developments of the last 50 years have been essentially based on their work as well as on the one of Fermi. Other books are: 1. J. Rueda and R. Ruffini, “Von Kernen zu den Sternen”, Springer, expected in 2016. 3. R. Ruffini, G.V. Vereshchagin and S.-S. Xue, “Oscillations and radiation from electron-positron plasma”, World Scientific, expected in 2016. 4. V. Belinski and E. Verdaguer, “Gravitational Solitons”, Second Edition, Cambridge University Press, expected in 2016. 5. V. Belinski, “Cosmological Singularity”, Cambridge University Press, expected in 2016. 6. D. Bini, S. Filippi and R. Ruffini, “Rotating Physical Solutions”, Springer, expected in 2016. 7. C.L. Bianco, L. Izzo, R. Ruffini and S.-S. Xue, “The Canonical GRBs”, World Scientific, expected in 2016. 8. H.C. Ohanian, R. Ruffini, “Gravitation and Spacetime”, Third Edition, Norton and Company, 2013.
An oral presentation by Pascal Chardonnet of the current situation of the IRAP PhD and the Erasmus Mundus program co-sponsored by the European Commission, as well as a report on the first 28 graduate students enrolled in the program (see enclosure 7). In 2015 ICRANet actively participated to the celebration of the International Year of Light under the aegis of UNESCO celebrating the 100^{th} Anniversary of the Einstein Equations and the Golden Jubilee of Relativistic Astrophysics. The main event was represented by the MG XIV Meeting held at the University of Rome “La Sapienza” from the 12^{th} to the 18^{th} of July 2015 (see Fig. 30), with the participation of 1200 scientists from more than 50 Countries. A series of satellite meetings was organized as well: the 2^{nd} César Lattes Meeting, Brazil, April 13 – 22, 2015; the 4^{th} Galileo-Xu GuangQi Meeting, Beijing, China, May 4 – 8, 2015; the 1^{st} Colombia-ICRANet Julio Garavito Armero Meeting, Bugaramanga – Bogotá, Colombia, November 23 – 27, 2015; the 1^{st} Sandoval Vallarta Caribbean Meeting, Mexico City, Mexico, December 1 – 5, 2015.
In conclusions, we have recently made a summary of ICRANet publications in the years 2013-2015, quoting explicitly the Impact Factor of each Journal where the publications appeared. I am very happy to include this list as a concluding remark:
Acknowledgements
I am happy to express, on behalf of all the Members of ICRANet and myself, our gratitude to the Ministers of Foreign Affairs, and to the Ministers of Economy and Finances, of Armenia, Brazil and Italy, and to the Vatican Secretary of State, as well as to the Presidents of the University of Arizona in Tucson, of the Stanford University, and of ICRA. We are grateful to the Brazilian Ambassador in Rome, H.E. Ricardo Neiva Tavares, as well as to the Scientific Attaché in Rome Dr. Luiz Felipe Czarnobai, for their assistance. We are equally grateful to the President of the Republic of Armenia, H.E. Mr. Serzh Sargsyan, to the Minister of Foreign Affairs of Armenia, H.E. Mr. Edward Nalbandian, to the Deputy Minister of Foreign Affairs of Armenia, H.E. Mr. Garen Nazarian, and to the Armenian Ambassador in Rome, H.E. Mr. Sargis Ghazaryan, for succeeding in finalizing the signature and implementation of the Seat Agreement for ICRANet in Armenia. We acknowledge the attention of Min. Roberto Cantone, Dr. Alessandra Pastorelli, and Prof. Immacolata Pannone, of the Italian Ministry of Foreign Affairs and International Cooperation. We also acknowledge the contact with the State Committee of Science of Armenia, the Ministério do Planejamento, Orçamento e Gestão of Brazil, and the Ragioneria Generale of the Ministry of Economy and Finances of Italy. A special recognition goes to the activities of the many Ambassadors and Consuls who have greatly helped in the intense series of activities carried out by ICRANet in Colombia, Brazil, China, Italy, Mexico. This year has been marked by the completion of the seat of Villa Ratti in Nice. We are grateful for this common effort to the President, Frédérique Vidal, and the Vice President, Stéphane Ngô Maï, of the University of Nice Sofia Antipolis. We are grateful to the Mayor of Pescara, Marco Alessandrini, to the Mayor of Nice, Christian Estrosi, to the Adjunct for Science, Research and Culture, Dr. Agnes Rampal, to the President of the National Academy of Science of Armenia, Prof. Radik Martirosyan, and to the Director of CBPF in Rio de Janeiro, Prof. Ronald Shellard, for their generous support in granting to ICRANet the logistics of the Centers in their respective townships. Clearly, a special mention of satisfaction goes to all the Scientific Institutions and Research Centers which have signed with us a collaboration agreement which include Al-Farabi Kazakh National University (Kazakhstan); ASI (Italian Space Agency, Italy), BSU (Belarusian State University, Belarus), CAPES (Brazilian Fed. Agency for Support and Evaluation of Grad. Education), CBPF (Brazil), State Government of Ceará (Brazil), CNR (National Research Council, Italy), ENEA (National Agency for new technologies, energy and the economic sustainable development, Italy), FAPERJ (Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Brazil), GARR (Italy), ICTP (The Abdus Salam International Center for Theoretical Physics, Italy), IFCE (Instituto Federal de Educação Ciência e Tecnologia do Ceará, Brasil), IHEP (Institute of High Energy Physics, Chinese Academy of Sciences, China), IHES (Institut des Hautes Études Scientifiques, France), INFN (National Institute for Nuclear Physics, Italy), INPE (Instituto Nacional de Pesquisas Espaciais, Brasil), ITA (Instituto Tecnológico de Aeronáutica, Brazil), LeCosPa (Leung Center for Cosmology and Particle Astrophysics, Taiwan), NASB (National Academy of Sciences, Belarus), NAS RA (National Academy of Science, Armenia), Nice University Sophia Antipolis (France), Pescara University “D’Annunzio” (Italy), SCSA (State Committee of Science of Armenia), UAM (Universidad Autónoma Metropolitana, México), UERJ (Rio de Janeiro State University, Brazil), UFF (Universidade Federal Fluminense, Brazil), UFPB (Universidade Federal da Paraíba, Brazil), UFPE (Universidade Federal de Pernambuco, Brazil), UFRGS (Universidade Federal do Rio Grande do Sul, Brazil), UFSC (Universidade Federal de Santa Catarina, Brazil), UIS (Universidad Industrial de Santander, Colombia), UNAM (Universidad Nacional Autonoma De Mexico), UnB (Universidade de Brasília, Brazil), UNIFEI (Universidade Federal de Itajubà, Brazil), University of Rome “Sapienza” (Italy), UNS (Universidad Nacional del Sur, Argentina). ICRANet, as sponsor of the IRAP-PhD program, expresses its gratitude to AEI – Albert Einstein Institute – Potsdam (Germany); Bremen University (Germany); Carl von Ossietzky University of Oldenburg (Germany); CBPF – Brazilian Centre for Physics Research (Brazil); Ferrara University (Italy); Indian centre for space physics (India); INPE (Instituto Nacional de Pesquisas Espaciais, Brasil); Institut Hautes Etudes Scientifiques – IHES (France); Inst. of High Energy Physics of the Chinese Academy of Science – IHEP-CAS, China; Max-Planck-Institut für Radioastronomie – MPIfR (Germany); Nice University Sophia Antipolis (France); Observatory of the Côte d'Azur (France); Rome University – “Sapienza” (Italy); Savoie University (France); Shanghai Astronomical Observatory (China); Stockholm University (Sweden); Tartu Observatory (Estonia) for their joint effort in creating and activating this first European Ph.D. program in Relativistic Astrophysics which has obtained the official recognition of the Erasmus Mundus program of the European Community. All these activities were achieved thanks to the dedicated work of Prof. Pascal Chardonnet. Finally, thanks goes to the Physics Department of the University of Rome “Sapienza” for all the collaboration with ICRA in the teaching, in the electronic links and in the common research. A special mention of gratitude, of course, goes to the administrative, secretarial and technical staff of ICRANet and ICRA for their essential and efficient daily support. |