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ICRANet Newsletter
April/May/June 2022
SUMMARY
1. ICRA - ICRANet press release "Gravitomagnetic interaction of a Kerr black hole with a magnetic field as the source of the jetted GeV radiation of gamma-ray bursts" 2. ICRANet GCN 32169, June 26, 2022 3. Prof. Remo Ruffini Festschrift. A conference in celebration of Prof. Remo Ruffini 80th birthday, May 16-18, 2022, Nice and online 4. MG16 Awards ceremony, May 17, 2022 (Nice, France) and June 1, 2022 (Moscow, Russia) 5. "Lunar eclipse and Mersenne Prize ceremony", a parallel meeting to Prof. Remo Ruffini Festschrift, May 16 - 18, 2022, Pescara and online 6. "Gerbertus' Meeting in tour", Rome, May 12, 2022 7. Prof. Ruffini at the presentation of the book "Somnium. Urla dall’Universo" by Ambassador Bruno Scapini, May 27, 2022, Rome 8. Dr Eduar Becerra, ICRANet PhD student and UIS, won the 2022 ICTP-SAIFR Prize in Classical Gravity and Applications, June 2022 9. New collaboration agreement between ICRANet and the University of Tabriz (Iran), April 26, 2022 10. Renewal of 3 ICRANet cooperation agreements with Istituto Nazionale di Astrofisica (INAF), University of Novi Sad (Serbia) and the University of Belgrade (Serbia) 11. Seminar by Dr Stanislav Komarov at ICRANet center, May 27, 2027 12. Scientific visits to ICRANet 13. Recent publications
1. ICRA - ICRANet press release "Gravitomagnetic interaction of a Kerr black hole with a magnetic field as the source of the jetted GeV radiation of gamma-ray bursts"
The new article coauthored by Rueda, J. A., Ruffini R., and Kerr P. R., Gravitomagnetic Interaction of a Kerr Black Hole with a Magnetic Field as the Source of the Jetted GeV Radiation of Gamma-Ray Bursts, has been published in the Astrophysical Journal, Volume 929, Number 1 on April 12, 2022. On that occasion, ICRA and ICRANet released a press release titled "Gravitomagnetic interaction of a Kerr black hole with a magnetic field as the source of the jetted GeV radiation of gamma-ray bursts".
FIG. 1. Figures taken from [1] with the kind permission of the authors. Left panel: electric (light blue) and magnetic (orange) field lines surrounding the rotating black hole. Electrons located in these northern and southern hemisphere cones of semi aperture angle of nearly 60◦ are outwardly accelerated leading to GeV photons. Right panel: helical motion of an electron around the magnetic field lines in the vicinity of the black hole leading to synchrotron radiation. A new theory explains the high-energy (photon energies of gigaelectronvolts — GeV) observed in the energetic long-duration gamma-ray bursts (GRBs) as originated in the vicinity of the black hole horizon. The theory, published today in The Astrophysical Journal [1] (https://iopscience.iop.org/article/10.3847/1538-4357/ac5b6e), led by an ICRA-ICRANet research team (some INAF associates), is based on the "inner engine" previously introduced by the team [2, 3]. The theory, which is also shown to work in active galactic nuclei (AGNs), proofs that the rotational energy of a black hole can indeed be extracted from the horizon of the black hole, and efficiently used to power the most energetic and powerful objects in the Universe. GRBs and binary-driven hypernovae. GRBs are one of the most complex astrophysical systems observed from ground and space in a wide window of the electromagnetic spectrum, including radio, optical, X-rays, gamma-rays in the megaelectronvolt (MeV) and the gigaelectronvolt (GeV) regimes, and ultrahigh-energy cosmic rays (UHECRs). GRBs are the most powerful transient sources of energies in the sky, releasing up to a few 1054 erg in just a few seconds. Therefore, the luminosity of a GRB is comparable to the sum of the luminosities of all the stars in the Universe!. The emission of an energetic GRB is characterized by seven Episodes produced by specific physical processes with widely different characteristic evolution timescales ranging from 10−14 s to 107 s or longer [4]. Although researchers soon identified that black holes must fuel GRBs, it is hard to think that a single object can explain all the above complexity. Another crucial piece of information is that one of such Episodes is an associated supernova explosion. How can a single astrophysical object lead to a supernova explosion, a black hole, and all the observed emissions at the different wavelengths? An answer to this question arises from the binary-driven hypernova (BdHN) model (see, e.g., [4], and references therein). In the BdHN scenario, the GRB originates in a binary system composed of a carbon-oxygen (CO) star and a neutron star (NS) companion. The CO star undergoes a core-collapse supernova, forming at its center a newborn neutron star, while the ejected material causes a massive accretion process onto the neutron star companion. The entity of the accretion process depends mostly on the orbital period, and only in tight binaries with orbital periods as short as a few minutes the accretion onto the neutron star companion induces its gravitational collapse, forming a newborn black hole. Three-dimensional numerical simulations of the above process in a BdHN were presented in [5]. The different fates of the binary explains the variety of GRBs, while the different physical components of the binary powered the different emission Episodes. The binaries in which the black hole is formed are called BdHN of type I. In a BdHN I, the rotational energy of the fast rotating, newborn neutron star and its interaction with the ejected material in the supernova powers the synchrotron radiation that explains the radio, optical, and X-rays emissions (see, e.g., [6]). Only the observed GeV emission [3, 7] is associated with the black hole and the process of energy extraction that is the topic of the new publication. Black holes are storehouses of energy. Black holes were initially conceptualized either as "dead" objects or as sinks of energy. Subsequently, it was realized that much as the thermodynamical systems, black holes may interact with their surroundings exchanging energy [8, 9]. This result led to one of the most important concepts in black hole physics and astrophysics: the Christodoulou-Ruffini-Hawking black hole mass-energy formula [8-10]. In its most general form, for a rotating charged black hole, it relates the black hole mass-energy to three independent pieces: its "irreducible mass, its charge, and its angular momentum. It led to a corollary of paramount importance in astrophysics: up to 50% of the mass-energy of a charged black hole, and up to 29% of the one of a rotating black hole, could be in principle extracted!. This extraordinary result led to the alternative view of black holes as storehouses of energy which nature could potentially use, and since then this concept has permeated for fifty years as of this writing, relativistic astrophysics both theoretically and experimentally. How much energy do we need to extract from black holes?. As we have mentioned above, researchers think that stellar-mass (i.e., of a few solar masses) black holes are involved in the emission of GRBs while, AGNs, releasing 1046 erg s−1 for billion years, must be powered by supermassive black holes of up to a few billion solar masses. However, the specific physical mechanism leading to the emission is up-to-now unknown, and theoretical efforts to find how to extract the black-hole energy have evanesced by the implausibility of their realization in nature (see, e.g. [11]). The existing models of AGN explain the observed jetted emission with massive jets powered by accretion disks around black holes, and GRBs models have inherited the same idea. These models have avoided, in practice, solving the problem of energy extraction from a black hole. Therefore, finding an astrophysically viable process that extracts the energy from a black hole has remained elusive. Because the efficiency of accretion power is low and, as such, very costly for nature, there was a need for new physics!. From charge to effective charge. A much more efficient mechanism for the acceleration of particles should use electromagnetic fields instead of pure gravity. In particular, electric fields can be great accelerators of charged particles. One could think of allowing the black hole to have stably some net charge that produces a stable electric field. This has been a most debated topic in astrophysics because, in principle, a charged black hole could be rapidly neutralized by absorbing an electric charge of the opposite sign to its charge. In 1973, Ruffini and Treves calculated the ground state configuration of a conducting rotating sphere endowed with charge and magnetic field [12]. In classical electromagnetism, Faraday induction implies that a rotating conductor in an external magnetic field generates an electric field. Accounting for this effect, they obtained the electromagnetic field structure of the configuration and showed that in its ground state, the electric charge of the object is not a free parameter: it has a precise value that depends on the mass and size of the object, the angular momentum, and the magnetic field strength. In 1974, R. Wald studied a similar question by analyzing a rotating black hole in an external magnetic field [13]. In this case, Einstein’s theory of general relativity predicts a unique effect based on the concept of gravitomagnetism: the interaction of the gravitational field of the rotating black hole with the magnetic field induces an electric field. This is somehow analogous to the Faraday induction, but here there is no charge generating that electric field! If we think of this electric field as produced by some charge, an effective charge, then the value of such an effective charge turns out to be determined, again, only by the black-hole angular momentum and the magnetic field strength. The existence of electric fields without electric charge has led to the possibility of astrophysical black holes being efficient particle accelerators without being electrically charged objects! The new physical mechanism. The engine presented in the new publication uses the above purely general relativistic effect of gravitomagnetism by considering a rotating black hole in an external magnetic field that induces the an electric field (see Figure 1). The theory exploits this induced electric field to accelerate charged particles (e.g. electrons/protons) in the vicinity of the black hole. Along the black hole rotation axis, the electrons are accelerated to energies of even thousands of PeV, so stellar-mass black holes in GRBs and supermassive black holes in AGNs can contribute to the observed flux of UHECRs using this mechanism. At off-axis latitudes, electrons accelerate to energies of hundreds of GeV and emit synchrotron radiation at GeV energies. This process occurs within 60◦ around the black hole rotation axis, and due to the equatorial-symmetry, it forms a double-cone of outgoing radiation. The black hole energy extraction. The energy carried out by this electromagnetic radiation is paid by the black hole which, in turn, loses its mass and angular momentum with time. This proves that we can efficiently extract energy from a rotating black hole to power the high-energy jetted emissions of GRBs and AGNs. The jetted emission does not originate from an ultra-relativistic acceleration of matter in bulk (e.g., massive jets powered by accretion disks), but from very special energy-saving general relativistic and electrodynamical process. A long march of successive theoretical progress and new physics discovered using GRBs has brought to this long-awaited result for about fifty years of relativistic astrophysics. We refer the interested reader to [1] for further details. As pointed out by the Referee: this paper pursues a very important problem in astrophysics, the generation of GRBs ... the problem of ultra-high energy radiation production using clean general relativistic approach. [1] J. A. Rueda, R. Ruffini, and R. P. Kerr, Astroph. J. 929, 56 (2022), arXiv: 2203.03471. [2] J. A. Rueda and R. Ruffini, European Physical Journal C 80, 300 (2020), 1907.08066. [3] R. Ruffini, R. Moradi, J. A. Rueda, L. Becerra, C. L. Bianco, C. Cherubini, S. Filippi, Y. C. Chen, M. Karlica, N. Sahakyan, et al., Astroph. J. 886, 82 (2019), 1812.00354. [4] R. Ruffini, R. Moradi, J. A. Rueda, L. Li, N. Sahakyan, Y. C. Chen, Y. Wang, Y. Aimuratov, L. Becerra, C. L. Bianco, et al., MNRAS (2021), 2103.09142. [5] L. Becerra, C. L. Ellinger, C. L. Fryer, J. A. Rueda, and R. Ruffini, Astroph. J. 871, 14 (2019), 1803.04356. [6] J. A. Rueda, R. Ruffini, M. Karlica, R. Moradi, and Y. Wang, Astroph. J. 893, 148 (2020), 1905.11339. [7] R. Moradi, J. A. Rueda, R. Ruffini, and Y. Wang, Astron. Astroph. 649, A75 (2021), 1911.07552. [8] D. Christodoulou, Phys. Rev. Lett. 25, 1596 (1970). [9] D. Christodoulou and R. Ruffini, Phys. Rev. D 4, 3552 (1971). [10] S. W. Hawking, Physical Review Letters 26, 1344 (1971). [11] R. Penrose and R. M. Floyd, Nature Physical Science 229, 177 (1971). [12] R. Ruffini and A. Treves, Astroph. Lett. 13, 109 (1973). [13] R. M. Wald, Phys. Rev. D 10, 1680 (1974). Press release on ICRANet website: http://www.icranet.org/communication/
2. ICRANet GCN 32169, June 26, 2022
TITLE: GCN CIRCULAR
NUMBER: 32169 SUBJECT: GRB 220527A: A BdHN I with a clear UPE phase DATE: 22/06/06 15:33:00 GMT FROM: Remo Rufinni at ICRA ruffini@icra.it R. Ruffini, Y. Aimuratov, L. Becerra, C.L. Bianco, Y.-C. Chen, C. Cherubini, S. Eslamzadeh, S. Filippi, M. Karlica, L. Li, G.J. Mathews, R. Moradi, M. Muccino, G.B. Pisani, F. Rastegarnia, J.A. Rueda, N. Sahakyan, Y. Wang, S.-S. Xue, on behalf of the ICRA, ICRANet-INAF team, report: GRB 220527A is observed by AGILE (Ursi et al. 2022, GCN 32129), Fermi (GCN 32130, Bissaldi et al. 2022, GCN 32131, Mangan et al. 2022, GCN 32133), Swift (B. Sbarufatti et al. 2022 GCN 32135, A. Tohuvavohu. 2022, GCN 32136), CALET (Yamaoka et al. 2022, GCN 32139), AstroSat (Gopalakrishnan et al. 2022, GCN 32140), and Konus-Wind (Lysenko et al. 2022, GCN 32152). With the redshift z = 0.857 of GRB 220527A (D. Xu et al. 2022, GCN 32141), the isotropic energy of this GRB in 10 keV - 10 MeV, and 20 keV - 16 MeV ranges are E_iso=(2.60 +\- 0.14)x10^{53} erg, and E_iso=1.22(-0.06,+0.07)x10^{53} erg, respectively (A. Lysenko et al. 2022, GCN 32152). The ultra-relativistic prompt emission phase of this GRB, originating from the over-criticl electric field around the black hole (Moradi et al 2021, Phys. Rev. D 104, 063043) extends from rest-frame time of 3.7s to 5.4s. The UPE phase is best fitted by a cutoff power-law plus blackbody spectrum (CPL+BB) with best fit parameters of: alpha = -0.57, Ep = 109.5 keV, beta = -2.36, kT = 47.8 keV. In addition to the above observations, the following observation of the GeV emission (E. Bissaldi et al. 2022, GCN 32131), originated from the newborn black hole (R. Ruffini et al. 2019 ApJ 886 82) and the afterglow emission (B. Sbarufatti et al. 2022 GCN 32135, A. Tohuvavohu. 2022, GCN 32136) originated from the newborn neutron star (J.A. Rueda et al. 2020 ApJ 893 148), confirm this GRB is a BDHN I. Following Ruffini et al. 2021 (MNRAS, 504, 5301,doi:10.1093/mnras/stab724), we predict the emergence of an optical supernova peak to be detected at (25.1+/-3.5) days after the trigger (June 21th 2022, uncertainty from June 18th 2022 to June 24th 2022), with the bolometric optical luminosity of L_SN,b=(9.0+/-2.7)x10^{42} erg/s. Follow-up optical observations for the SN peak are encouraged.
3. Prof. Remo Ruffini Festschrift. A conference in celebration of Prof. Remo Ruffini 80th birthday, May 16-18, 2022, Nice and online
Prof. Remo Ruffini Festschrift, a conference in celebration of Prof. Ruffini’s 80th birthday, has been held from May 16 to 18, 2022 at ICRANet Seat Villa Ratti in Nice (France). An hybrid event, both face-to-face and online, was adopted.
More than 90 speakers from 26 different countries joined the conference, delivering scientific presentations, remembering the important role played by Prof. Ruffini in the field of Relativistic Astrophysics, or just sharing with the audience some good memories with Prof. Ruffini and their warmest greetings. Among them: Yerlan Aimuratov (ICRANet, Fesenkov Astrophysical Institute), Lorenzo Amati (INAF OAS), Stefano Ansoldi (University of Udine), Carlos Arguelles (UNLP, CONICET), Xinhe Bao (President of USTC), Laura Becerra (Pontificia Universidad Católica de Chile), Donato Bini (CNR), Yifu Cai (USTC), Pascal Chardonnet (attaché for scientific cooperation at the French Embassy in Algeria), Pisin Chen (LeCoSpa), Christian Cherubini (University Campus Bio-medico of Rome), Demetrios Christodoulou (ETH Zurich), Zigao Dai (USTC, Nanjing University), Thibault Damour (IHES), Massimo Della Valle (INAF), Nathalie Deruelle (IHES), Hansjoerg Dittus (ZARM, University of Bremen), Simonetta Filippi (University Campus Bio-medico of Rome), Christopher Fryer (Los Alamos National Laboratory), Jiangong Gao, Daniele Gregoris (Jiangsu University of Science and Technology), Mimoza Hafizi (University of Tirana), Wenbiao Han (SHAO), Luca Izzo (University of Copenhagen), Robert Jantzen (Villanova University), Vladimir Karas (Czech Academy of Sciences), Roy Kerr (University of Canterbury, New Zeland), Claus Laemmerzahl (ZARM, University of Bremen), Giovanni Lamanna (LAPP), Liang Li (ICRANet), Manuel Malheiro (Istituto Tecnologico de Aereonautica -ITA), Grant Mathews (University of Notre Dame), Felix Mirabel (IAFE Argentina, CEA Saclay), Rahim Moradi (ICRANet), Ehud Nakar (Tel Aviv University), Tsvi Piran (Hebrew University of Jerusalem), Peter Predehl (MPE), Brian Punsly (ICRANet), Sang Pyo Kim (Gunsan National University), Hernando Quevedo (UNAM), Johann Rafelski (University of Arizona), José Rodriguez (UIS, ICRANet), Jorge Rueda (ICRANet Ferrara), Sara Saghafi (University of Mazandaran), Narek Sahakyan (Director ICRANet Seat in Armenia), Stefano Scopel (Sogang University, CQeST), Soroush Shakeri (Isfahan University of Technology), Zhiqiang Shen (Director General SHAO), Costantino Sigismondi (ICRANet), Yousef Sobouti (IASBS), Rashid Sunyaev (IKI, Russian Academy of Sciences), Marco Tavani (INAF), Saken Toktarbay (Al-Farabi Kazakh University), Aldo Treves (University of Insubria), Gregory Vereshchagin (ICRANet), Yu Wang (ICRANet), Hyung Won Lee (Inje University), Shesheng Xue (ICRANet), Yefei Yuan (USTC), Alexander Zakharov (ITEP), Cesar Zen Vasconcellos (UFRGS), Bing Zhang (University of Nevada) and Yunlong Zheng (USTC). Fig. 2: From left to right: Dr Agnès Rampal, assistant of the Mayor of Nice, Dr Xavier Latour, Vice-president of the Métropole Nice Côte d’Azur, Prof. Pascal Chardonnet and Prof. Jorge Rueda, visiting the ICRANet Seat at Villa Ratti during their visit on May 17, 2022. Some of these speakers, participated in person and went to Villa Ratti in Nice to join Prof. Ruffini. Also Dr Agnès Rampal, assistant of the Mayor of Nice and Dr Xavier Latour, Vice-president of the Métropole Nice Côte d’Azur joined the meeting in person on May 17, the day of Prof. Ruffini’s birthday, in order to express him their sincere greetings, also on behalf of the Mayor of Nice, H.E. Christian Estrosi. The rich program of the meeting was articulated in 4 main sessions, in order to accommodate all the different time zones and to facilitate the participation of many speakers from all over the world. The one organized every day in the early morning was mainly devoted to the connections with China, Korea and Iran. This was followed by a morning session, a lunch break one (which both saw the participation of many scientists from Europe) as well as by an afternoon one, mainly attended by scientist from North and South America. The meeting webpage is available at the following link: https://indico.icranet.org/event/3/. The recordings of the different sessions are now available on the ICRANet YouTube channel, at the following link: https://www.youtube.com/playlist?list=PLr5RLbSWSonvwinAmihhTf675um9A_GqZ
4. MG16 Awards ceremony, May 17, 2022 (Nice, France) and June 1, 2022 (Moscow, Russia)
On the occasion of the conference in celebration of Prof. Ruffini’s 80th birthday, the official ceremony to deliver the MG16 Awards’ statues in person to the Awardees has been also organized. The MG16 meeting took place from July 5 to 10, 2021 only online, in observance of the Covid-19 safety regulations which then imposed strict restrictions to travels and meetings’ organization. The MG16 Awards have been therefore presented at ICRANet Seat in Villa Ratti in Nice on May 18, 2022 by Prof. Nathalie Deruelle, Prof. Jorge Rueda and Prof. Narek Sahakyan to Prof. Tsvi Piran (Hebrew University of Jerusalem), Prof. Peter Predehl (on behalf of Max Planck Institute for Extraterrestrial Physics - MPE) and Prof. Rashid Sunyaev (on behalf of Space Research Institute IKI of the Russian Academy of Sciences).
At the end of the MG16 Awards ceremony, Prof. Piran and Prof. Sunyaev left their signatures on the wall of Villa Ratti, next to those of other eminent personalities (scientists, politicians, artists, ...) who visited the center. On June 1, 2022 the MG16 Award has been delivered in person to Prof. Alexander Shirshakov (on behalf of S.A. Lavochkin Association, part of Roskosmos), who received this award back in 2021. The solemn ceremony was organized in the museum of the enterprise in Moscow (Russia). This award has been attributed for "the unique achievements in the study of Black Holes, in particular for the very precise X-ray map of the sky". "Spektr-RG is a great project. This is really so. So much has been done. I wish to add that this project allowed to grow the whole new generation of engineers, developers and manufacturers. I sincerely believe that this award is not the last one." - said the first deputy Director, Aleksandr Shirshakov during the delivery of the award. "The award is cast is silver and represents the projection of particle orbits around the rapidly rotating Black Holes" - said the PI of the Spektr-RG project, the head of the division of high energy astrophysics in the Institute for Space Research (IKI) of the Russian Academy of Sciences, Rashid Sunyaev. "This is almost the limiting rotation of the black hole, and here is a number of particle trajectories represented" - he said, giving the award to the first deputy Director of the Lavochkin association.
Some press relases on that event (in Russian) are available at the following links: • https://360tv.ru/news/mosobl/npo-imeni-lavochkina-v-himkah-poluchil-mezhdunarodnuju-premiju/?utm_source=yxnews&utm_medium=desktop • https://www.laspace.ru/press/news/events/010620222/ • https://tass.ru/kosmos/14791015?utm_source=google.com&utm_medium=organic&utm_campaign=google.com&utm_referrer=google.com • https://novosti-kosmonavtiki.ru/news/83790/ • https://www.interfax.ru/russia/844440
5. "Lunar eclipse and Mersenne Prize ceremony", a parallel meeting to Prof. Remo Ruffini Festschrift, May 16 - 18, 2022, Pescara and online
On the occasion of the 80th birthday of Prof. Remo Ruffini, Director of ICRANet and President of ICRA, as well as on the occasion of the total eclipse of the Moon in 2022, Prof. Costantino Sigismondi, ICRANet collaborator, organized and chaired a parallel meeting at the ICRANet center in Pescara from May 16 to 18, 2022.
The meeting was attended by the students from 2 classes of Galileo Galilei High School in Pescara, under the supervision of their tutor, Prof. Tiziana Pompa. It started on Monday, May 16 from 4 to 6 AM in Lanciano (Abruzzo, Italy) with the online lunar eclipse observations and the sunrise at 256 m above the sea level, horizon's depression and refraction. The meeting went on from 3 to 4 PM at the ICRANet center in Pescara, starting with a visit of the center by the students. Then, Prof. Sigismondi presented a talk on the differential measures of ΔUT1 at the meridian line of Santa Maria degli Angeli in Rome and Prof. J.M. Pasachoff (by remote connection), presented a talk titled "preliminary analysis on the Lunar Total Eclipse of May 16,2022: is there still science with eclipses?". From 8 to 10 PM, Prof. Sigismondi organized an observation of the sunset behind the hills and of the moonrise from the canal harbor of Pescara, still in opposition to the Sun, as well as an observation of the transit of the international space station and of its instant immersion in the shadow of the Earth (as has been for the eclipse of Moon) at h 21:01:24. On Tuesday May 17, Prof. Sigismondi organized in Pescara. from 5 to 6 AM, the observation of Venus, Jupiter, Mars and Saturn and Sunrise at the sea level. These observation have been followed in the afternoon by a presentation on the solar forcing to climate change. Immediately after, there was an official ceremony for the attribution of the Mersenne Prizes 2022 by Dr Carlo Masci, Mayor of Pescara, in honor of Prof. Remo Ruffini’s 80th birthday. This event was in fact broadcasted and inserted in the program of Prof. Ruffini Festschrift, which was ongoing. Inspired by the figure of Marino Mersenne (1588-1648), than European referent for all the scientists, ICRANet promoted and established this prize in 2019, with the sponsorship of the IAU Commission on History of Astronomy (Commission C3) and ideally continues his work in the field of Relativistic Astrophysics, representing a strong network of scientists from all over the world. Several eminent students have been awarded by the Mayor of Pescara, namely Daniele Spalletti (Galileo Ferraris Technical Institute- Rome), Gabriele Orsini (Galileo Ferraris Technical Institute- Rome) and Giulia Andreasi Bassi (Galileo Ferraris Technical Institute- Rome) for the 2022 edition of the Mersenne Prize; Aurora Delli Rocioli (Galileo Galilei High School- Pescara) and Diego Guglielmi (Galileo Ferraris Technical Institute- Rome) for the 2021 edition; and Christian Genghini (IIS Federico Caffè- Rome), Francesco Di Iacovo (IIS Federico Caffè- Rome), Gabriele Becagli (IIS Federico Caffè- Rome) and Roberta Chaicchiaretta (Galileo Galilei High School- Pescara) for the 2020 edition. For the press release on that event: http://www.icranet.org/communication/16052022/ita.pdf For the article appeared on the local newspaper "Il Centro": https://www.ilcentro.it/pescara/studenti-scienziati-i-premiati-1.2876541 This theoretical section was also integrated with the podcast materials prepared by Prof. Sigismondi. The program of the event and all the relevant podcast materials, can be found at the following link: http://www.icranet.org/index.php?option=com_content&task=view&id=1444
6. "Gerbertus' Meeting in tour", Rome, May 12, 2022
The annual congress in honor of Gerbert of Aurillac, scientist, scholastic astronomer and Pope, took place on May 12, 202 and has been coordinated, as the previous ones, by Prof. Costantino Sigismondi, ICRANet collaborator, at international level. This year, it has been organized as a "meeting in tour" in 3 main places, symbolic for Gerbertus.
The meeting started at 11 AM on Thursday May 12, 2022 from the papal Basilica of Santa Maria Maggiore in Rome. The Sun and the Moon in the apse of this Basilica have been made by Jacopo Torriti in the 13th century. The Latin inscription below Jesus and Mary says "Maria Virgo Assumpta Est ad Aethereum Thalamum in quo Rex Regum Stellato Sedet Solio". The Virgin Mary has been assumpted at the heavenly thalamus, where the King of kings sits on the starry throne where Gerbert-Sylvester II guided a famous procession in the night of August 15, 1000 to the Lateran. After this visit, the meeting moved to the Basilica of Santa Croce in Gerusalemme, where Gerbert celebrated mass on May 3, 1003 and started to be ill. A legend appeared in 1080 AD (William of Malmesbury) attributed to Gerbert the invention of an automat. It predicted that Gerbert will not die if not going to Jerusalem, and the mass in Santa Croce "in Jerusalem" represented the violation to the "immortality condition" obtained by the magic automat. The meeting moved then to the Basilica of San Giovanni in Laterano, where the epitaph of Gerbertus’ tomb is still there, included by Francesco Borromini in the renovation of the Basilica in 1648, upon the will of Pope Benedict XIV (founder of the Pontifical Academy of Sciences). Beyond the legend of his tomb, which would emit humidity for the death of a Pope or a Cardinal, and beyond another one about his body cut in pieces (false, upon verification in 1648), Gerbert of Aurillac (ca 938-12 May 1003) was renowned as the greatest scholar of his time. Bishop of Reims, Ravenna and Rome he "jumped from R to R in R" in his three archbishoprics, in a period of time characterized by the rule that a Bishop could not change site. Gerbert of Aurillac introduced in Europe the Astrolabe and the Abacus from the Arabs, even inventing new algorithms for speeding their calculations. He was also a music theorist and organ builder, as well as a philosopher who anticipated Scholastic school. His epistolary is the vaster of his time, showing a fine politician, geographer, scientist, teacher and pastor. A special guest of this event was Prof. Luca Montecchio (UniEcampus), historian and author of "Gerberto d'Aurillac. Silvestro II" with graphe.it (2011). For the website of the meeting: http://www.icra.it/gerbertus/gerb-tour2022.htm For the history of the previous meetings since 2003: http://www.icra.it/gerbertus
7. Prof. Ruffini at the presentation of the book "Somnium. Urla dall’Universo" by Ambassador Bruno Scapini, May 27, 2022, Rome
On May 27, 2022, Prof. Ruffini has been invited to intervene on the occasion of the presentation of the book "Somnium. Urla dall’Universo" by Ambassador Bruno Scapini, former Ambassador of Italy in the Republic of Armenia.
The book, edited by Calibano, has been presented in the conference room of Hotel Donna Laura Palace in Rome (Italy). Ambassador Scapini claims that geopolitics is now moving also to the space and that its militarization could be the risk that humanity could face in the future. In this work, Scapini reports the story of Timothy Sanders, young astrophysicist and aspirant astronaut of NASA, who detects from the Observatory of Mount Palomar, the approaching of a mysterious object not identified. This discovery involves him in a tricky espionage affair between USA and Russia, as well as in a dangerous love story. Anyway, Sanders will discover the creator of this nefarious militarization project only after a series of adventures in which he will also risk his life. The event has been moderated by Dr Maria Grazia De Angelis, President of the italian association for the study of the work for the organizational development and saw the participation of the literary critic, Prof. Marina Pratici, and of Prof. Remo Ruffini, Director of ICRANet. During his intervention, Prof. Ruffini thanked Ambassador Scapini for his kind invitation and illustrated his recent research and results achieved also thanks to the constant collaboration with his research group as well as with scientists from all over the world. Every day, every minute and every second, thanks to the observations and to the data analysis, they are making new discoveries which contribute to understand always more the structure of our Universe. For more information about that event (in Italian): http://www.ln-international.net/home/news/10597/bruno-scapini--presenta-a-roma-il-suo-ultimo-romanzo--somnium-urla-dall-universo https://kmetro0.it/2022/05/29/somnium-urla-dalluniverso-fantapolitica-o-realta/
8. Dr Eduar Becerra, ICRANet PhD student and UIS, won the 2022 ICTP-SAIFR Prize in Classical Gravity and Applications, June 2022
It is our pleasure to announce that Dr Eduar Becerra (ICRANet PhD student and Universidad Industrial de Santander-Bucaramanga, Colombia) obtained an honorable mention for the 2022 ICTP-SAIFR Prize in Classical Gravity and Applications for "Geodesics in space-time of self-gravitating dark matter and its application to stellardynamics around the Galactic center".
The annual competition for the 2022 ICTP-SAIFR Prize in Classical Gravity and Applications has been created to stimulate the growth of a Latin-American community in the rapidly evolving research areas related to gravitational wave observations. This prize recognizes doctoral thesis research of outstanding quality and achievement in the area of classical gravity and its applications in gravitational wave physics, astrophysics and cosmology. The annual award consists of $1000 Brazilian reais, a certificate, and travel and local expenses to present an invited talk at the annual ICTP-SAIFR Workshop on Classical Gravity and Applications. For the webpage of the Prize: https://www.ictp-saifr.org/gravityprize/
9. New collaboration agreement between ICRANet and the University of Tabriz (Iran), April 26, 2022
On April 26, 2022 ICRANet has signed a new Cooperation protocol with the University of Tabriz in Iran. The Cooperation Protocol has been signed by Dr Safar Nasrollahzadeh (Chancellor of the University of Tabriz), by Prof. Amin Rezaei Akbarieh (Faculty of Physics at University of Tabriz), by Prof. Remo Ruffini (Director of ICRANet) and by Prof. Narek Sahakyan (Director of ICRANet Seat in Armenia).
The agreement will be valid for 5 years and the main joint activities to be developed under their framework include: the promotion of theoretical and observational activities within the field of Relativistic Astrophysics; the institutional exchange of faculty members, researchers, post-doctorate fellows and students; the promotion of technological developments; the development of Data Centers for Astrophysical data in all wavebands; the organization of training and teaching courses, seminars, conferences, workshops or short courses, the development of inter-institutional research areas associated to local graduate programs and joint publications. For the text of the agreement: http://www.icranet.org/index.php?option=com_content&task=view&id=1445
10. Renewal of 3 ICRANet cooperation agreements with Istituto Nazionale di Astrofisica (INAF), University of Novi Sad (Serbia) and the University of Belgrade (Serbia)
Renewal of the cooperation agreement between ICRANet and Istituto Nazionale di Astrofisica (INAF), March 25, 2022
On April 7, 2022, ICRANet has received the official confirmation that the agreement between ICRANet and Istituto Nazionale di Astrofisica (INAF) has been renewed. The renewal was signed on March 25, 2022 by Prof. Marco Tavani (President of INAF) and by Prof. Remo Ruffini (Director of ICRANet). This agreement will be valid for further 3 years and the main joint activities to be developed under its framework include: the promotion of theoretical and observational activities within the field of Relativistic Astrophysics; the institutional exchange of faculty members, researchers, post-doctorate fellows and students; the promotion of technological developments; the development of Data Centers for Astrophysical data in all wavebands; the organization of training and teaching courses, seminars, conferences, workshops or short courses, the development of inter-institutional research areas associated to local graduate programs and joint publications.
For the text of the agreement: http://www.icranet.org/inaf
Renewal of the cooperation agreement between ICRANet and the University of Novi Sad (Serbia), May 27, 2022
On May 27, 2022, the cooperation protocol between ICRANet and the University of Novi Sad (UNS) has been renewed. The renewal was signed by Prof. Dejan Madić (Rector of UNS), by Prof. Milica Pavkov-Hrvojević (Dean Faculty of Sciences UNS), by Prof. Remo Ruffini (Director of ICRANet) and by Prof. Jorge Rueda (ICRANet Faculty Professor). This agreement will be valid for further 5 years and the main joint activities to be developed under its framework include: the promotion of theoretical and observational activities within the field of Relativistic Astrophysics; the institutional exchange of faculty members, researchers, post-doctorate fellows and students; the promotion of technological developments; the development of Data Centers for Astrophysical data in all wavebands; the organization of training and teaching courses, seminars, conferences, workshops or short courses, the development of inter-institutional research areas associated to local graduate programs and joint publications.
For the text of the agreement: http://www.icranet.org/novi-sad
Renewal of the cooperation agreement between ICRANet and the University of Belgrade (Serbia), June 21, 2022
On June 21, 2022, the cooperation protocol between ICRANet and the University of Belgrade sad has been renewed. The renewal was signed by Prof. Vladan Đokić (Rector of the University of Belgrade) and by Prof. Remo Ruffini (Director of ICRANet). This agreement will be valid for further 5 years and the main joint activities to be developed under its framework include: the promotion of theoretical and observational activities within the field of Relativistic Astrophysics; the institutional exchange of faculty members, researchers, post-doctorate fellows and students; the promotion of technological developments; the development of Data Centers for Astrophysical data in all wavebands; the organization of training and teaching courses, seminars, conferences, workshops or short courses, the development of inter-institutional research areas associated to local graduate programs and joint publications.
For the text of the agreement: http://www.icranet.org/belgrade
11. Seminar by Dr Stanislav Komarov at ICRANet center, May 27, 2027
On Friday, May 27, 2022, Dr Stanislav Komarov (Belarusian State University and ICRANet center in Minsk) presented a seminar titled "Spectrum of electromagnetic radiation of a particle, falling into Schwarzschild black hole" with the following abstract:
The purpose of the work is determination of electromagnetic field of a test charge moving in the vicinity of a black hole, as well as determination of the spectrum of its electromagnetic radiation. We use multiple expansion of electromagnetic potential to find solution of the problem. The announcement of the seminar has also been published on ICRANet website: http://www.icranet.org/index.php?option=com_content&task=blogcategory&id=89&Itemid=781
12. Scientific visits to ICRANet
• Prof. Massimo Della Valle (Osservatorio di Capodimonte - Italy), April 11 - 12, 2022
• Dr. Stanislav Komarov (Belarusian State University, ICRANet center in Minsk - Belarus), May 9 - 30, 2022 • Prof. Yerlan Aimuratov (Fesenkov Astrophysical Institute and al-Farabi Kazakh National University), June 11 - July 31, 2022 • Tursynbek Yernazarov (Al-Farabi Kazakh National University), June 23 - September 10, 2022 • Mohamed Gadri (University of Tripoli), June 28 - July 2, 2022 During their visit, those scientists had an opportunity to discuss their scientific research and to have fruitful exchange of ideas with other researchers from ICRANet and from different parts of the world.
13. Recent publications
J. A. Rueda, R. Ruffini, R. P. Kerr, Gravitomagnetic Interaction of a Kerr Black Hole with a Magnetic Field as the Source of the Jetted GeV Radiation of Gamma-Ray Bursts, published on Aprile 12, 2022 on ApJ, Volume 929, Number 1.
We show that the gravitomagnetic interaction of a Kerr black hole (BH) with a surrounding magnetic field induces an electric field that accelerates charged particles to ultra-relativistic energies in the vicinity of the BH. Along the BH rotation axis, these electrons/protons can reach energies of even thousands of petaelectronvolts, so stellar-mass BHs in long gamma-ray bursts (GRBs) and supermassive BHs in active galactic nuclei can contribute to the ultrahigh-energy cosmic rays thorough this mechanism. At off-axis latitudes, the particles accelerate to energies of hundreds of gigaelectronvolts and emit synchrotron radiation at gigaelectronvolt energies. This process occurs within 60° around the BH rotation axis, and due to the equatorial symmetry, it forms a double-cone emission. We outline the theoretical framework describing these acceleration and radiation processes, how they extract the rotational energy of the Kerr BH and the consequences for the astrophysics of GRBs. DOI: https://doi.org/10.3847/1538-4357/ac5b6e J. Sedaghata, S.M. Zebarjadab, G.H. Bordbarac, B. Eslam Panah, Structure of Magnetized Strange Quark Star in Perturbative QCD, published in Physics Letters B 829 (2022), 137032. We have performed the leading order perturbative calculation to obtain the equation of state (EoS) of the strange quark matter (SQM) at zero temperature under the magnetic field B= 1018 G. The SQM comprises two massless quark flavors (up and down) and one massive quark flavor (strange). Consequently, we have used the obtained EoS to calculate the maximum gravitational mass and the corresponding radius of the magnetized strange quark star (SQS). We have employed two approaches, including the regular perturbation theory (RPT) and the background perturbation theory (BPT). In RPT the infrared (IR) freezing effect of the coupling constant has not been accounted for, while this effect has been included in BPT. We have obtained the value of the maximum gravitational mass to be more than three times the solar mass. The validity of isotropic structure calculations for SQS has also been investigated. Our results show that the threshold magnetic field from which an anisotropic approach begins to be significant lies in the interval 2 x 1018 G < B < 3 x 1018 G . Furthermore, we have computed the redshift, compactness and Buchdahl-Bondi bound of the SQS to show that this compact object cannot be a black hole. DOI: https://doi.org/10.1016/j.physletb.2022.137032 Hajar Noshad, Seyed Hossein Hendi and Behzad Eslam Panah, Neutron Stars in Mimetic Gravity, published on May 3, 2022 in European Physical Journal C 82 (2022) 394. In this paper, a modified version of the hydrostatic equilibrium equation based on the mimetic gravity in the presence of perfect fluid is revisited. By using the different known equation of states, the structural properties of neutron stars are investigated in general relativity and mimetic gravity. Comparing the obtained results, we show that, unlike general relativity, we can find the appropriate equation of states that support observational data in the context of mimetic gravity. We also find that the results of relativistic mean-field-based models of the equation of states are in better agreement with observational data than non-relativistic models. DOI: https://doi.org/10.1140/epjc/s10052-022-10358-1 Sahakyan, N.; Giommi, P., A thirteen-year-long broadband view of BL Lac, accepted for publication in MNRAS on April 12, 2022. We present the results of an extensive analysis of the optical, ultraviolet, X-ray and γ-ray data collected from the observations of the BL Lac objects prototype BL Lacertae carried out over a period of nearly 13 years, between August 2008 and March 2021. The source is characterized by strongly variable emission at all frequencies, often accompanied by spectral changes. In the γ-ray band several prominent flares have been detected, the largest one reaching the flux of Fγ( > 196.7 MeV) = (4.39 ± 1.01) × 10-6 photon cm-2 s-1. The X-ray spectral variability of the source during the brightest flare on MJD 59128.18 (06 October 2020) was characterized by a softer-when-brighter trend due to a shift of the synchrotron peak to ~1016 Hz, well into the HBL domain. The widely changing multiwavelength emission of BL Lacertae was systematically investigated by fitting leptonic models that include synchrotron self-Compton and external Compton components to 511 high-quality and quasi-simultaneous broad-band spectral energy distributions (SEDs). The majority of selected SEDs can be adequately fitted within a one-zone model with reasonable parameters. Only 46 SEDs with soft and bright X-ray spectra and when the source was observed in very high energy γ-ray bands can be explained in a two-zone leptonic scenario. The HBL behaviour observed during the brightest X-ray flare is interpreted as due to the emergence of synchrotron emission from freshly accelerated particles in a second emission zone located beyond the broad line region. DOI: https://doi.org/10.1093/mnras/stac1011 Middei, Riccardo; Giommi, Paolo; Perri, Matteo; Turriziani, Sara; Sahakyan, Narek; Chang, Y. L.; Leto, C.; Verrecchia, F., The first hard X-ray spectral catalogue of Blazars observed by NuSTAR, accepted for publication in MNRAS on May 2022. Blazars are a peculiar class of active galactic nuclei (AGNs) that enlighten the sky at all wavelengths. The electromagnetic emission of these sources is jet-dominated resulting in a spectral energy distribution (SED) that has a typical double-humped shape. X-ray photons provide a wealth of information on the physics of each source as in the X-ray band we can observe the tail of SED first peak, the rise of the second one or the transition between the two. NuSTAR, thanks to its capability of focusing X-rays up to 79 keV provides broadband data particularly suitable to compute SEDs in a still poorly explored part of the spectrum. In the context of the Open Universe initiative we developed a dedicated pipeline, NuSTAR_Spectra, a shell-script that automatically downloads data from the archive, generates scientific products and carries out a complete spectral analysis. The script homogeneously extracts high level scientific products for both NuSTAR's telescopes and the spectral characterisation is performed testing two phenomenological models. The corresponding X-ray properties are derived from the data best-fit and the SEDs are also computed. The systematic processing of all blazar observations of the NuSTAR public archive allowed us to release the first hard X-ray spectroscopic catalogue of blazars (NuBlazar). The catalogue, updated to September 30th, 2021, includes 253 observations of 126 distinct blazars, 30 of which have been multiply observed. ArXiv: https://arxiv.org/abs/2205.05089 MAGIC collaboration, Proton acceleration in thermonuclear nova explosions revealed by gamma rays, published on April 14, 2022 in Nature Astronomy. Classical novae are cataclysmic binary star systems in which the matter of a companion star is accreted on a white dwarf1,2. Accumulation of hydrogen in a layer eventually causes a thermonuclear explosion on the surface of the white dwarf3, brightening the white dwarf to ~105 solar luminosities and triggering ejection of the accumulated matter. Novae provide the extreme conditions required to accelerate particles, electrons or protons, to high energies. Here we present the detection of gamma rays by the MAGIC telescopes from the 2021 outburst of RS Ophiuchi, a recurrent nova with a red giant companion, which allowed us to accurately characterize the emission from a nova in the 60 GeV to 250 GeV energy range. The theoretical interpretation of the combined Fermi LAT and MAGIC data suggests that protons are accelerated to hundreds of gigaelectronvolts in the nova shock. Such protons should create bubbles of enhanced cosmic ray density, of the order of 10 pc, from the recurrent novae. DOI: https://doi.org/10.1038/s41550-022-01640-z Shesheng Xue, Spontaneous Peccei-Quinn symmetry breaking renders sterile neutrino, axion and χboson to be candidates for dark matter particles, accepted for publication in Nuclear Physics B. We study the Peccei-Quinn (PQ) symmetry of the sterile right-handed neutrino sector and the gauge symmetries of the Standard Model. Due to four-fermion interactions, spontaneous breaking of these symmetries at the electroweak scale generates top-quark Dirac mass and sterile-neutrino Majorana mass. The top quark channel yields massive Higgs, W± and Z0 bosons. The sterile neutrino channel yields the heaviest sterile neutrino Majorana mass, sterile Nambu-Goldstone axion (or majoron) and massive scalar χboson. Four-fermion operators effectively induce their tiny couplings to SM particles. We show that a sterile QCD axion is the PQ solution to the strong CP problem. The lightest and heaviest sterile neutrinos (meN∼102 keV and mtN∼102 GeV), a sterile QCD axion (ma<10−8 eV, gaγ<10−13GeV−1) and a Higgs-like χboson (mχ∼102 GeV) can be dark matter particle candidates, for the constraints of their tiny couplings and long lifetimes inferred from the W-boson decay width, Xenon1T and precision fine-structure-constant experiments. The axion and χboson couplings to SM particles are below the values reached by current laboratory experiments and astrophysical observations for directly or indirectly detecting dark matter particles. ArXiv: https://arxiv.org/abs/2012.04648 |