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ICRANet Newsletter



Bulletin ICRANet
Juillet/Aout/Septembre 2022



RÉSUMÉ
1. Communiqué de presse ICRA - ICRANet "GRB 190829A - A Showcase of Binary Late Evolution"
2. La 6ème Bego Rencontre Summer School, 4 - 14 Juillet 2022, Nice et en ligne
3. Annonce du 5ème Zeldovich meeting, 12 - 17 Juin 2023, Erevan (Arménie)
4. La Nuit européenne des chercheurs, 30 Septembre 2022, meeting en ligne
5. Nouveaux accords de coopération signés par ICRANet
6. Participation d'ICRANet au meeting IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics, 5-9 Septembre 2022, Guatemala et en ligne
7. Participation d'ICRANet à la Bad Honnef Physics School, 5-9 Septembre 2022, Bad Honnef (Allemagne)
8. Participation d'ICRANet au 31ème Texas Symposium on Relativistic Astrophysics, 12-16 Septembre 2022, Prague (République Tchèque)
9. Participation du Prof. Ruffini à la conférence "La diplomatie culturelle entre l'Italie et les Amériques", 7 Juillet 2022, Sénat italien à Rome (Italie)
10. Le Prof. Massimo Della Valle, Président du Comité scientifique d'ICRANet, nommé membre correspondant de l'Académie des Lincei
11. Numéro spécial de Philosophical Transactions A de la Royal Society Publishing "The future of mathematical cosmology (part 1)", collectionné et édité par le Prof. Spiros Cotsakis et le Prof. Alexander Yefremov
12. Visites scientifiques auprès d'ICRANet
13. Publications récentes


1. Communiqué de presse ICRA - ICRANet "GRB 190829A - A Showcase of Binary Late Evolution"

GRB 190829A is the fourth closest gamma-ray burst (GRB) to date (z = 0.0785). Owing to its wide range of radio, optical, X-ray, and especially the very-high-energy (VHE) observations by H.E.S.S., it has become an essential new source examined by various models with complementary approaches.


Fig 1. Ongoing accretion process onto the νNS and the NS companion simulated in Becerra et al. (2019). The νNS is located at the center of the dark blue spot, and is accreting the surrounding material. The SN ejecta are also being accreted by the NS companion, which is located at the center of the green spot. We also notice that the expansion of SN ejecta is distorted by the companion NS and a part of the SN ejecta is flowing back to the νNS. This process creates a unique feature of BdHNe: the fallback accretion onto the νNS is enhanced creating a second peak of accretion at about an orbital-period time after the SN explosion (see, e.g., Becerra et al. 2019, for more details).


The traditional fireball model of GRBs is based on a single system, at times indicated as a "collapsar", possibly a Black Hole (BH), giving origin to an ultra-relativistic jetted emission. The slowing down of such a jet in the interstellar medium has been assumed to explain the main properties of the GRBs in all wavelengths. These results have been expressed, prior to 2002, in many reviews, see e.g. Shemi and Piran 1990, Fishman and Meegan 1995, Piran 2000, Van Paradijs et al 2000, Meszaros 2002. The review of Meszaros traces back the historical developments of GRB theories at a time the observations were the domain of gamma-ray astronomy observed by the BATSE instrument in the 20 to 600 KeV and the EGRET instrument in the 20 MeV to 30 GeV both on board the Compton CGRO satellite.
Our model based on a binary system was proposed in 2012 (Rueda & Ruffini 2012) and has been in development for one decade. Our approach was motivated by an alternative set of data following the launching of the Beppo-SAX satellite with on board the Wide Field X-rays camera which promoted a direct collaboration between the gamma-ray community and the much larger X-ray community. In the meantime, indeed following the UHURU satellite, a large number of X-ray missions including the Einstein telescope, the Chandra telescope, and the XMM were developed leasing to the discovery of the first black hole in our galaxy , Cygnus X1, the binary X-ray sources, and the structure galactic halos. The extragalactic origin of the GRBs, made possible by the discovery of the X-ray afterglow, did open an additional collaboration with the new class of large optical telescopes including Keck and the VLT. A new era linking GRBs to supernovae started. New space missions followed by the AGILE telescope in the GeV range, the Neil Gehrels Swift Observatory and the Fermi telescope in the MeV, GeV and TeV, recently involving also the MAGIC telescopes. A detailed high-quality data from the new observations made clear the new complexity of the GRB structure, composed of selected independent episodes each one characterized by a specific spectral feature observed in their rest frame. We advanced in 2012 a basic change of paradigm based on binary systems: the Binary driven Hypernovae (BdHN). The physical picture evolved gradually including the needed physics that allowed to study of a wide range of binary parameters including the explosion energy, the mass, the binary separation, the density profile, the equations of state and et al., as well as the statistical analysis of different GRB components (Ruffini et al. 1999, 2000, 2010, 2015; Wang et al. 2015; Ruffini et al. 2018a,b; Wang et al. 2018; Ruffini et al. 2018c; Wang et al. 2019b; Ruffini et al. 2019; Rueda et al. 2020; Rueda & Ruffini 2020; Moradi et al. 2021b; Ruffini et al. 2021). The numerical simulations of the occurring physical processes have been upgraded from one dimension (Fryer et al. 2014) to two-dimensions (Becerra et al. 2015), to three-dimensions (Becerra et al. 2016, 2019). The latest simulations (Becerra et al. 2019) implemented a smoothed particle-hydrodynamics (SPH) method, and examined a large selection of initial conditions and the outcomes of the binary system after the SN explosion, see Fig 2, Rueda et al. (2019) and Rueda et al. (2021) have reviewed the entire development process. The case of GRB 190829A is indeed the first detailed verification of the validity of a BDHN model in view of the exceptionality of the available data.


Fig. 2: Luminosity of GRB 190829A including the data from H.E.S.S (yellow) for TeV, Fermi-GBM (orange dots), Swift- BAT (purple triangles) for the prompt emission of hard X-ray and gamma-ray, Swift-XRT (blue crosses) for the soft X-ray (absorbed), GTC (green diamonds) for the optical i band, from which the SN 2019yw is extracted (red diamonds), the optical signal of SN over-shots the optical emission from the synchrotron, and AMI-LA (brown stars) for the radio observation. Top right corner: The count rate of GRB 190829A prompt emission from the raw data of Fermi-GBM: The first pulse is from −0.75 s to 8.05 s, indicated by the orange dotted line, and the second pulse is from 46.50 s to 64.00 s, indicated by the green dashed line.


Unlike the traditional fireball model, the BdHN model considers a central engine that arises in the final evolutionary stage of the CO core in the presence of a binary NS companion. An SN explosion occurs, it triggers the GRB emission and generates a νNS. Therefore, in addition to the physical processes of single-star collapse models, we need to consider not only the binary interactions but also the appearance of the νNS, see Fig 2. The most influential interactions are the accretion of SN ejecta onto the NS companion and the fallback accretion onto the νNS spins it up. The afterglow is produced by the mildly relativistic expanding SN ejecta which contains a large number of electrons accelerated by the kinetic energy of the SN and the energy injection from the rapidly spinning νNS and its subsequently spin-down. Unlike the BdHN I, which were by the hypercritical accretion of the SN ejecta into the NS companion form a BH, here we describe GRB 190829A by a BdHN II where no BH is formed but a more massive NS.
The low redshift characteristic of GRB 190829A makes it possible to have detailed temporal observations of various bands, hence GRB 190829A becomes the first GRB to fully exhibit the final evolution of this special class of binary systems. Our BdHN II model has been successfully applied on this burst, explaining its prompt emission composed of two pulses, its radio, optical and X-ray afterglow, as well as the emergence of the SN signal, as follows:
As the COcore gravitationally collapses, an SN explosion occurs and a newborn NS (νNS) originates at its center. Most of the SN energy (~ 1053 erg) is deposited in the neutrino, about a few percent of energy goes to the kinetic energy of SN ejecta (~1051−1052 erg), which expands outward at velocities of around 0.1 c. The low-density outermost layer has the highest speed while the denser regions expand with slower velocities. After a few minutes, the SN ejecta reaches the companion NS, and the hypercritical accretion starts. The accretion rate onto the companion NS rises exponentially and peaks in a few minutes. The numerical simulations show that the entire hypercritical accretion process may last for hundreds of minutes, but the peak accretion rate of more than 10−4 Mā˜‰ s−1, supplied by the high density and slow-moving part of the SN ejecta, holds only for tens of seconds to tens of minutes depending on the binary separation, see Fig. 1, The accretion translates into an electromagnetic power of 1048-1049 erg s−1 assuming a 10% of efficiency in the conversion from gravitational to radiation energy. This procedure of accretion onto the companion NS in a 20-40 minutes orbital period binary system well explains the first prompt pulse of GRB 190829A.
In the meanwhile, some matter falls back leading to an accretion process onto the νNS, see Fig 2. This fallback accretion is significantly amplified by the companion NS which alters the trajectory of a partial SN ejecta that flows back to the νNS. The accretion onto the νNS has two components, the first is the typical fallback matter the same as the case of the SN from a single star, it leads the accretion rate to reach a peak to then decay nearly as a power-law with time. The peak luminosity produced by it is weak < 1048 erg s−1 and can hardly be seen for cosmological distances. The second is the unique feature of the binary system, the presence of the companion enhances the fallback onto the νNS creating the second peak of accretion, see Fig 1. The second part contributes most to the accreting mass for a duration of about an orbital-period time. The fallback accretion also transfers angular momentum to the νNS, spinning it up to a rotation period of a few milliseconds. So the peak luminosity from the fallback accretion is in the order of 1048-1049 erg s−1. The fallback accretion onto the νNS explains the second prompt pulse of GRB 190829A.
The fallback accretion continues as a source injecting energy into the mildly relativistic expanding SN ejecta, as well as the spin-down energy from the νNS. The synchrotron emission from the SN ejecta leads to the afterglow. We adopt the associated synchrotron emission for explaining the radio, optical and X-ray afterglow emissions. Contrary to the traditional model which assumes the origin of synchrotron emission from an ultra-relativistic jet, we here assume that the ejecta expands at a constant velocity at a wide angle. Second, our magnetic field is from the νNS, we assume that at large distances from the νNS, beyond its light cylinder, the magnetic field decreases linearly with distance. This implies that the magnetic field strength felt by the expanding ejecta evolves with time. Third, the energy injection in the synchrotron originates from the fallback accretion and the spin-down of νNS. Our numerical computation shows that a νNS spinning at an 8 ms period with a dipole field of 5 × 1012 Gauss and quadruple field of about 1 × 1014 Gauss, and an SN ejecta moving at 109 cm s-1 generates the observed radio, optical and X-ray afterglows.
We do not explain the origin of VHE emission observed in the 0.2-4 TeV energy band of H.E.S.S. neither by the above synchrotron model, nor the synchrotron self-Compton process: the synchrotron self-Compton emission peaks at a few hundreds of MeV, cutoffs at < 10 GeV, and has a lower luminosity to the observed in the H.E.S.S. energy bandwidth. However, the similar power-law behavior of the VHE and the X-ray light curves observed as well in GRB 190114C and GRB 180720B see e.g. Acciari et al., 2019 and Abdalla et al., 2019 allow us to advance the hypothesis the VHE can be related to some transient activity possibly related to a new physics originating in the νNS.
The BdHN model naturally contains an SN, which produces ~0.4Mā˜‰ nickel whose radioactive decay energy is emitted mainly at optical wavelengths with a corresponding flux that peaks around ~13 days in the source rest-frame, common to all other GRBs (Aimuratov et al 2022, in preparation), and indeed it was observed by GTC.
Having succeeded in this special case of BdHN II GRB 190829A we are now progressing in the explanation of the BdHN I GRB 910114C and in the case of BdHN III GRB 170215A.

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2. The 6th Bego Rencontre Summer School, July 4 - 14, 2022, Nice and online

The 6th Bego Rencontre Summer School, 4 - 14 Juillet 2022, Nice et en ligne
La 6ème Bego Rencontre Summer School a eu lieu du 4 au 14 Juillet 2022 à la fois en personne auprès du Siège ICRANet de Villa Ratti à Nice (France) et en ligne.

L'école aimait à discuter des développements récents dans la théorie et les observations des sursauts gamma (GRBs), des noyaux galactiques actifs (AGNs) et de la matière sombre (DM). Certains sujets discuté concernant les GRBs et les AGNs étaient:
• le procès d'extraction d'énergie de un trous noir rotatifs (BHs) dans la inner engine de l'émission à haute énergie des GRBs longs et des AGNs. Une attention particulière a été donnée aux inner engines qui comprennent un trous noir de Kerr immergé dans un champ magnétique et un plasma ionisé. Les développements récents sur ce sujet ont été illustrés, en particulier le problème du criblage du champ, de la décharge électrique, des propriétés de radiation, de la physique des trous noirs, de la magnétohydrodynamique et du maximum de charge électrique admissible dans les inner engines;
• les évolutions récents dans la théorie des GRB, par exemple dans le model de binary-driven hypernova (BdHN). Ça inclut l'explication physique de la phase d'émission prompte ultra relativiste (UPE) dans le régime de MeV, l'émission des dernières lueurs dans les rayons X, les longueurs d'onde optiques et radio et l'émission de GeV;
• La Supernova associé aux GRBs et le rôle de l'explosion de la supernova dans l'émission de un GRB long;
• GRBs fortement décalées et cosmologie des GRB;
• l'émission des cocons GRB (observations);
• l'émission de M87* (théorie et observations).

Certains sujets discuté concernant la matière sombre ont été:
• matière sombre fermionique et bosonique: microphysique;
• matière sombre fermionique et bosonique: macrophysique;
• développements récents dans la description du centre galactique (Sgr A*) en tant que cœur de la matière sombre;
• dernières observations astrométriques des étoiles orbitant Sgr A* et contraintes observationnelles sur la nature de Sgr A*;
• Dernières nouvelles sur le contenu baryonique dans les galaxies;
• Forte lentille gravitationnelle;
• Matière sombre dans la cosmologie primordiale, simulations cosmologiques et formation du halo de matière sombre.


Plus de 90 participants de 19 différents pays ont participé au meeting conférence et plusieurs conférences ont été présentées par les Profs. Yerlan Aimuratov, Lorenzo Amati, Carlos Raul Arguelles, Davide Astesiano, Laura Becerra, Carlo Luciano Bianco, Stefano Bondani, Kunatay Boshkayev, Valentina Crespi, Mariateresa Crosta, Maria Giovanna Dainotti, Massimo Della Valle, Christopher Fryer Daniele Gregoris, Luca Izzo, Petr Kotlarik, Liang Li, Francesco Longo, Wentao Luo, Nick Mavromatos, Massimo Meneghetti, Martin Mestre, Felix Mirabel, Rahim Moradi, Ehud Nakar, Florian Peissker, Vahe Petrosian, Tsvi Piran, Federico Re, Paola Re Fiorentin, José Rodriguez, Piero Rosati, Jorge Rueda, Narek Sahakyan, Costantino Sigismondi, Alessandro Spagna, Eleonora Troja, Gregory Vereshchagin, Matteo Viel, Yu Wang, Eli Waxman, Shesheng Xue, Rafael Yunis et Bing Zhang.
Le site web de la conférence est disponible au suivant lien: https://indico.icranet.org/event/4/
Les enregistrements des différentes sessions sont disponibles sur le canal YouTube d' ICRANet: https://www.youtube.com/channel/UCU19scWRGvlIiKBcN1QXCRQ



3. Annonce du 5ème Zeldovich meeting, 12 - 17 Juin 2023, Erevan (Arménie)


C'est avec plaisir que nous vous informons que l'ICRANet est en train d'organiser le 5ème Zeldovich meeting, une conférence internationale en l'honneur de Ya. B. Zeldovich, qui se tiendra à Erevan (Arménie) du 12 au 17 Juin 2023. Cette conférence fera suite à une série de conférences internationales très réussies en l'honneur de Ya. B. Zeldovich, qui ont eu lieu respectivement à Minsk en 2009, 2014, 2018 et en ligne en 2020.
Les sujets qui seront couverts pendant cette conférence incluent l'exceptionnellement vaste gamme d'intérêts de recherche de Ya. B. Zeldovich, qui vont de la chimie physique, des particules élémentaires et de la physique nucléaire à l'astrophysique et la cosmologie:
• astrophysique multimessanger;
• Univers primordial, structure de grandes-échelles, micro-ondes cosmique de fond;
• étoiles à neutrons, trous noirs, sursauts gamma, supernovae, hypernovae;
• ondes gravitationnelles;
• quantum et gravité.

Traditionnellement, entre les orateur invités, il y auront des membres de l'école scientifique d'astrophysique et cosmologie fondée par Ya. B. Zeldovich, bien connue dans tout le monde.
L'inscription au meeting est maintenant ouverte.
Toutes les informations sur cette conférence seront disponible sur son site web: http://www.icranet.org/zeldovich5



4. La Nuit européenne des chercheurs, 30 Septembre 2022, meeting en ligne

à l'occasion de la Nuit européenne des chercheurs 2022, l'ICRANet, en collaboration avec le Prof. Costantino Sigismondi (collaborateur d'ICRANet) a organisé une conférence en ligne, afin de créer une occasion agréable de discussion entre les chercheurs et les étudiants. Cette manifestation, comme chaque année, a attiré beaucoup de monde, en offrant aux participants une opportunité pour prendre partie dans les activités scientifiques qui visent à illustrer encore mieux le rôle fondamental jouée par la science.
Le meeting en ligne a eu lieu Vendredi 30 Septembre 2022 à partir de 16 :30 h. Après les remarques d'ouverture, le Prof. Remo Ruffini, Directeur d'ICRANet, a présenté une conférence sur les Supernovae et les développements récents de l'astrophysique relativiste. Après lui, le Prof. Liang Li et le Prof. Wang Yu, tous les deux Professeurs de la Faculté d'ICRANet, ont présenté 2 conférences respectivement sur les progénitures des Supernovae et sur les modèles numériques. Ensuite, le Prof. Costantino Sigismondi a parlé de Antares et de la variabilité stellaire, de la mesure du radius de la Terre, ainsi que de l'ICRANet et son rapport avec les lycées. Il a aussi discuté avec les participants des perspectives présentes et à venir de la science concernant les Supernovae et les étoiles binaires.


Fig. 3: 456 observations de Antares en 2014.

Il a expliqué que la plupart des étoiles se trouvent dans des systèmes multiples et les interactions entre leurs composants peuvent déterminer le déclanchement pour l'explosion d'une Supernova, le phénomène le plus lumineux dans l'Univers. Les systèmes des étoiles binaires et les progénitures des Supernovae sont 2 sujets qui ont attiré les études théoriques depuis longtemps. Les modèles numériques sophistiqués, basés sur les équations de la Relativité Générale, nécessaires quand la masse et la dimension de l'objet stellaire puissent la matière à surmonter la densité du noyau atomique, nous permettent, aujourd'hui, de représenter les données d'observations avec grande précision. Au même temps, les données d'observations s'enrichissent d'informations multi-spectrales reçues d'un nombre toujours croissant d'instruments, consacrés à la détection du ciel dans toutes ses longueurs d'ondes, à la fois de la Terre et de l'espace: ça c'est ce qui a été présenté par le Profs. Li et Wang.


Fig. 4: schéma géométrique du méthode de Ératosthène pour la mesure du radius de la Terre (Federico Battistol, Liceo Scarpa di Motta di Livenza (TV)

L'observation de la variabilité stellaire de la rouge et super géant Antares, registrée dans les dernières 8 années, a été le principal sujet présenté et commenté par le Prof. Sigismondi: gammes de quelques centièmes de magnitudes sont visibles aussi à l'œil nu, à condition que soit corrigée, pour l'extinction atmosphérique, la comparaison avec des étoiles de même luminosité, qui se trouvent à une dizaine de degrés loin de Antares. Les observations faites par le satellite SOHO complètent le cadre. Le concept de magnitude et l'échelle logarithmique des luminosités, à la base d'une interprétation correcte des phénomènes astrophysiques, ont été présenté aussi aux étudiants.



5. Nouveaux accords de coopération signés par ICRANet

Nouveau accord de collaboration entre l'ICRANet et le Fesenkov Astrophysical Institute (Kazakhstan), 5 Aout 2022


Le 5 Aout 2022, l'ICRANet a signé un nouveau protocole de coopération avec le Fesenkov Astrophysical Institute en Kazakhstan. Ce protocole a été signé par le Prof. Chingis Omarov (Directeur du Fesenkov Astrophysical Institute), par le Prof. Yerlan Aimuratov (Fesenkov Astrophysical Institute), par le Prof. Remo Ruffini (Directeur d'ICRANet) et par le Prof. Jorge Rueda (Professeur de la Faculté d'ICRANet).
Ce protocole demeurera valide pour 5 années et les principales activités conjointes qui seront développées dans le cadre de cet accord comptent: la promotion des activités de recherche et d'observation dans le champ de l'astrophysique relativiste; la collaboration entre des membres de la Faculté, des chercheurs, des post-doctorat fellows et des étudiants; l'organisation de séminaires, conférences, workshops, cours de formations et de recherche, et publications conjointes.
Pour le texte du protocole: http://www.icranet.org/index.php?option=com_content&task=view&id=1451


Nouveau accord de collaboration entre l'ICRANet et AEROSPACIFIC (Colombie), 1 Septembre 2022


Le 1 Septembre 2022, l'ICRANet a signé un nouveau protocole de coopération avec l'AEROSPACIFIC cluster en Colombie. Ce protocole a été signé par le Dr Cesar Augusto Rodriguez Adaim (Président de AEROSPACIFIC) et par le Prof. Remo Ruffini (Directeur d'ICRANet).
Ce protocole demeurera valide pour 5 années et les principales activités conjointes qui seront développées dans le cadre de cet accord comptent: la promotion des activités de recherche et d'observation dans le champ de l'astrophysique relativiste; la collaboration entre des membres de la Faculté, des chercheurs, des post-doctorat fellows et des étudiants; l'organisation de séminaires, conférences, workshops, cours de formations et de recherche, et publications conjointes.
Pour le texte du protocole: http://www.icranet.org/index.php?option=com_content&task=view&id=1452


Nouveau accord de collaboration entre l'ICRANet et l'Iranian National Observatory (INO), 8 Septembre 2022


Le 8 Septembre 2022, l'ICRANet a signé un nouveau protocole de coopération avec l'Iranian National Observatory (INO) en Iran. Ce protocole a été signé par le Prof. Habib Khosroshahi (Directeur de l'INO) et par le Prof. Remo Ruffini (Directeur d'ICRANet).
Ce protocole demeurera valide pour 5 années et les principales activités conjointes qui seront développées dans le cadre de cet accord comptent: la promotion des activités de recherche et d'observation dans le champ de l'astrophysique relativiste; la collaboration entre des membres de la Faculté, des chercheurs, des post-doctorat fellows et des étudiants; l'organisation de séminaires, conférences, workshops, cours de formations et de recherche, et publications conjointes.
Pour le texte du protocole: http://www.icranet.org/documents/agreementICRANet-INO.pdf


Nouveau accord de collaboration entre l'ICRANet et l'Indian Center for Space Physics, 21 Septembre 2022


Le 21 Septembre 2022, l'ICRANet a signé un nouveau protocole de coopération avec l'Indian Center for Space Physics en Inde. Ce protocole a été signé par le Prof. Sandip Chakrabarti (Directeur de l'Indian Center for Space Physics) et par le Prof. Remo Ruffini (Directeur d'ICRANet).
Ce protocole demeurera valide pour 5 années et les principales activités conjointes qui seront développées dans le cadre de cet accord comptent: la promotion des activités de recherche et d'observation dans le champ de l'astrophysique relativiste; la collaboration entre des membres de la Faculté, des chercheurs, des post-doctorat fellows et des étudiants; l'organisation de séminaires, conférences, workshops, cours de formations et de recherche, et publications conjointes.
Pour le texte du protocole: http://www.icranet.org/index.php?option=com_content&task=view&id=1453



6. Participation d'ICRANet au meeting IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics, 5-9 Septembre 2022, Guatemala et en ligne

Du 5 au 9 Septembre 2022, le Professeur Remo Ruffini, Directeur d'ICRANet a été invite à donner une conférence plénière à l'occasion du meeting "IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics". Ce meeting était le 10ème d'une série de meetings, qui réunit les scientifiques qui travaillent dans le domaine de la physique des astroparticules, de la cosmologie, de la gravitation, de la physique nucléaire et des domaines connexes. Le meeting a eu lieu à la fois en personne en Guatemala et en ligne.


Le lundi 5 Septembre, le Prof. Ruffini a donné sa présentation en ligne, titrée "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs", voici ci-dessous le résumé:
A profound difference has occurred in the analysis of GRBs initially analyzed in the domain of Gamma-ray astronomy with the Compton Gamma Ray Observatory and the BATSE Detector with the extension to X-Ray Astronomy and optical astronomy introduced by Beppo SAX and the KEK and VLT optical observatory, followed by the AGILE, Fermi mission, Niels Gehrels SWIFT mission as well as HEHSS and MAGIC observations.
An authentic "Copernican revolution" has occurred in the transition from the traditional model of GRBs originating in a single star progenitor (collapsar) to GRBs with a binary progenitor composed of a CO core and a companion NS.
We evidence from 24 SN observations related to GRBs that all of them, once analyzed with the general relativistic corrections can be identified with I Bc Sn with a common value of the Luminosity and common time of occurrence of the peak of the optical emission .this can be understood in term of a precursor composed of a CO core and a binary NS companion. By contrast, the GRBs differ profoundly in their energetic which can be expressed in terms of 3 different classes of BDHNe: BDHNI, BDHNII, BDHN III, also originating from Precursors composed of a CO core and a Binary companion.
It is pointed out how the analysis of these systems has profoundly modified the concept of the BH and the associated fundamental physics necessary for their description since the "introducing of the Black Hole" by Ruffini and Wheeler in 1971. At first, it is illustrated how the most radical change has occurred in the introduction of the effective BH charge, with an electric field only function of the BH dimensionless spin and a background magnetic field Bo. This definitely indicates the abandon of the Kerr-Newmann solution in favor of the Kerr metric, for energy extraction processes in BH physics. We then enter in the detailed description of the "seven Seals", the seven Episodes characterizing GRB 190114c and the associated SN 1998 bW.

Le proceedings du meeting seront publiés par Astronomische Nachrichten.
Pour le site web du meeting: https://indico.cern.ch/event/921532/



7. Participation d'ICRANet à la Bad Honnef Physics School, 5-9 Septembre 2022, Bad Honnef (Allemagne)

Du 5 au 9 Septembre 2022, le Professeur Remo Ruffini, Directeur d'ICRANet a été invite à présenter une conférence à l'occasion de la Bad Honnef Physics School à Bad Honnef (Allemagne), avec le Prof. Liang Li et le Prof. Rahim Moradi (tous les deux Professeurs de la Faculté d'ICRANet).
Cette école était dédiée aux aspects observationnels, théoriques et aussi épistémologique de la physiques des trous noirs et portaient sur les thèmes suivants: définition provisoire d'un trous noir, évidence d'observation et possibles explications alternatives pour les trous noirs, formation d'un trou noir, structure global et causalité de l'espace-temps du trous noir, définition rigoureuse d'un trou noir, théorème de la singularité, unicité des solutions du trou noir (théorème no-hair), propriétés de stabilité, trous noirs dans les théories généralisées de la gravité, trous noirs dans modèles avec gravité analogue, domaine quantique dans l' espace-temps du trous noir, trous noirs en propre gravité quantique, aspects épistémologiques et philosophiques des trous noirs. Ce meeting a été co-organisé par le Prof. Dr. Domenico Giulini (ITP, Université de Hanovre & ZARM, Université de Brème), la Dr. Eva Hackmann (ZARM, Université de Brème) et le Prof. Dr. Claus Lämmerzahl (ZARM, Université de Brème).
Le jeudi 8 Septembre, le Prof. Ruffini, suivi par le Prof. Li et le Prof. Moradi, a donné une conférence titrée "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs", voici ci-dessous le résumé:
A profound difference has occurred in the analysis of GRBs initially analyzed in the domain of Gamma-ray astronomy with the Compton Gamma Ray Observatory and the BATSE Detector with the extension to X-Ray Astronomy and optical astronomy introduced by Beppo SAX and the KEK and VLT optical observatory, followed by the AGILE, Fermi mission, Niels Gehrels SWIFT mission as well as HEHSS and MAGIC observations.
An authentic "Copernican revolution" has occurred in the transition from the traditional model of GRBs originating in a single star progenitor (collapsar) to GRBs with a binary progenitor composed of a CO core and a companion NS.
We evidence from 24 SN observations related to GRBs that all of them, once analyzed with the general relativistic corrections can be identified with I Bc Sn with a common value of the Luminosity and common time of occurrence of the peak of the optical emission .this can be understood in term of a precursor composed of a CO core and a binary NS companion. By contrast, the GRBs differ profoundly in their energetic which can be expressed in terms of 3 different classes of BDHNe: BDHNI, BDHNII, BDHN III, also originating from Precursors composed of a CO core and a Binary companion.
It is pointed out how the analysis of these systems has profoundly modified the concept of the BH and the associated fundamental physics necessary for their description since the "Introducing of the Black Hole" by Ruffini and Wheeler in 1971. At first, it is illustrated how the most radical change has occurred in the introduction of the effective BH charge, with an electric field only function of the BH dimensionless spin and a background magnetic field Bo. This definitely indicates the abandonment of the Kerr-Newmann solution in favor of the Kerr metric, for energy extraction processes in BH physics. After we enter in the detailed description of the "seven Seals", the seven Episodes characterizing GRB 190114c and the associated SN 1998 bW. We finally enter into the quantum and classic electro dynamical process describing the energy extraction of a BH in the UPE phase of GRBs, in the GeV emission of GRBs, in the emission of synchrotron radiation from spinning NS. Turn then to specific examples in GRB 190114c (Moradi and Liang Li) in GRB 171205 A and GRB 190829A (Wang Yu). Possible presence of Jorge if compatible with Space-time situation.

Pour le site web de l'école: https://www.dpg-physik.de/veranstaltungen/2022/black-holes



8. Participation d'ICRANet au 3ème Texas Symposium on Relativistic Astrophysics, 12-16 Septembre 2022, Prague (République Tchèque)

Du 12 au 16 Septembre 2022, le Professeur Remo Ruffini, Directeur d'ICRANet a été invite à présenter une conférence à l'occasion du 31ème Texas Symposium on Relativistic Astrophysics, qui a eu lieu à Prague (République Tchèque). Avec lui, aussi le Prof. Rahim Moradi et le Prof. Yu Wang (tous les deux Professeurs de la Faculté d'ICRANet) ont été invités à présenter une conférence à cette occasion.


Fig. 5: photo de group de tous les participants au 3ème Texas Symposium on Relativistic Astrophysics à Prague.

Depuis 1963, le Texas Symposium à été un des meetings principales en Astrophysique Relativiste. Traditionnellement, il se déplace dans tout le monde et a lieu chaque 2 années dans des villes différentes. Le principaux sujets abordés pendant la conférence étaient la gravité (classique, numérique, quantum, modifié, tests), la relativité (trous noirs, étoiles à neutrons, accrétion, réacteurs), multimessanger (rayons cosmiques, neutrinos, rayons gamma, rayons X, ondes gravitationnelles), la cosmologie (fond diffus cosmologique, re-ionisation, Univers primordial, structure à grande échelle, matière sombre), ainsi que des sessions spéciales dédiées au Télescope Event Horizon, à GRAVITY, Polarimétrie des rayons X et au James Webb Space Telescope.

Le mercredi 14 Septembre, le Prof. Ruffini a présenté sa conférence, titrée "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs", voici ci-dessous le résumé:


Fig. 6: Le Prof. Remo Ruffini pendant la présentation de sa conférence à l'occasion du 31ème Texas Symposium on Relativistic Astrophysics à Prague, 14 Septembre 2022.

Following the Beppo SAX mission, the exponential growth of observatories in all wavelengths ranging from radio optical, all the way to X-ray, Mev, Gev, Tev radiation prolific of an exponential growth of data which have been following in the recent 25 years. For this, the BDHN model was started by the concept of induced gravitational collapse (Rueda and Ruffini 2012), evolved collaboration with Los Alamos National Lab and Chris Freyer. The binary model assumes as a progenitor a binary system composed of a Co Core and a binary NS companion see FiG. Three different BDHN types exist mainly as a function of their binary period. The collapse of the Co Core leads to the SN explosion with the creation of a νNS (pulsar) which originates the X-ray afterglow. Starting from these results we can as well pose new problems to be addressed: 1) the possible nature of SN 1054 as a GRB; 2) The universality of the X-ray afterglow in all long GRBs originating from the pulsar; 3) the understanding of the Supernova explosion, including the formation of the new neutron star (pulsar).

Dans le même jour, le Prof. Yu Wang a présenté sa conférence, titrée "GRB 190829A - A Showcase of Binary Late Evolution", voici ci-dessous le résumé:


Fig. 7: Le Prof. Yu Wang pendant la présentation de sa conférence à l'occasion du 31ème Texas Symposium on Relativistic Astrophysics à Prague, 14 Septembre 2022.

GRB 190829A is the fourth closest gamma-ray burst (GRB) to date (z=0.0785). We show in GRB 190829A, that the double-prompt pulses and the multiwavelength afterglows are consistent with the type II binary-driven hypernova (BdHN II) model. The progenitor is a binary composed of a carbon-oxygen (CO) star and a neutron star (NS) companion. The gravitational collapse of the iron core of the CO star produces a supernova (SN) explosion and leaves behind a new neutron star (νNS) at its center. The accretion of the SN ejecta onto the NS companion and onto the νNS via matter fallback spins up the NSs and produces the double-peak prompt emission. The synchrotron emission from the expanding SN ejecta with the energy injection from the rapidly spinning νNS and its subsequent spin-down leads to the afterglow in the radio, optical, and X-ray. We model the sequence of physical and related radiation processes in BdHNe and focus on individuating the binary properties that play the relevant roles.

Le jeudi 15 Septembre, le Prof. Rahim Moradi a présenté sa conférence, titrée "Nature of the ultra-relativistic prompt emission (UPE) phase in GRB 180720B and GRB 190114C", voici ci-dessous le résumé:


Fig. 8: Le Prof. Rahim Moradi pendant la présentation de sa conférence à l'occasion du 31ème Texas Symposium on Relativistic Astrophysics à Prague, 15 Septembre 2022.

We investigate the ultra relativistic prompt emission (UPE) of GRB 180720B and GRB 190114C, observed by Fermi-GBM. The time-resolved spectral analysis performed in time sub-intervals reveals the UPE hierarchical structure: the spectrum in each shorter time interval is always fitted by a composite blackbody plus cutoff power-law model. This structure is explained using the inner engine of a binary-driven hypernova (BdHN) model operating in the quantum electrodynamics (QED) regime. The electric field induced by the gravitomagnetic interaction of the newborn Kerr BH with the surrounding magnetic field is overcritical in this regime. The overcritical field polarizes the vacuum, resulting in an electron-positron pair plasma that loads baryons from its surroundings during its expansion. The dynamics of the self-acceleration of pair-electromagnetic-baryon (PEMB) pulses to their point of transparency are calculated. The radiation timescale, Lorentz factors, and transparency radius of the PEMB pulses are determined to characterize the quantum vacuum polarization process in the sequences of decreasing time bins of the UPE. We also estimate the strength of the surrounding magnetic field and derive a lower limit to the BH mass, and a corresponding upper limit to the spin parameter, under the assumption that the UPE is powered by Kerr BH extractable energy and its mass is bound from below by the NS critical mass.

Pour le site web du meeting: https://texas2021.org/



9. Participation du Prof. Ruffini à la conférence "La diplomatie culturelle entre l'Italie et les Amériques", 7 Juillet 2022, Sénat italien à Rome (Italie)

Le 7 Juillet 2022, le Prof. Ruffini a été invite à participer à la conférence "La diplomatie culturelle entre l'Italie et les Amériques", qui a eu lieu dans la sala Capitolare du Sénat italien à Rome (Italie).
La conférence a été organisée par le Sénateur italien Pier Ferdinando Casini, en collaboration avec le groupe de réflexion américain Renaissance Evolution, et vise à la promotion de la culture en tant que moteur pour le dialogue, l'harmonie et la richesse antre les personnes et les pays. Certaines personnalités éminentes ont participé à la conférence et ont pris la parole, telles que le Ministre italien pour la culture Dario Franceschini, l'Archevêque Vincenzo Paglia, l'Ambassadeur d'Italie à Santo Domingo Stefano Queirolos Palmas, le secrétaire général de l'organisation internationale italien- latin - américaine Antonella Cavallari, ainsi que l'expert de géopolitique Michele Pavan et l'analyste politique Tim Phillips.
Pour la vidéo de la conférence: https://www.youtube.com/watch?v=xTDPZFOTuHI



10. Le Prof. Massimo Della Valle, Président du Comité scientifique d'ICRANet, nommé membre correspondant de l'Académie des Lincei

C'est avec grand plaisir que nous vous informons que le Prof. Massimo Della Valle, Directeur de l'Observatoire astronomique de Capodimonte et Prédisent du Comité scientifique d'ICRANet a été nommé membre correspondant de l'Académie des Lincei le 28 Juillet 2022, pour la division de Sciences physiques.
Pour lire la nouvelle sur le site web de l'Académie des Lincei: https://www.lincei.it/it/news/nuovi-soci-2022



11. Numéro spécial de Philosophical Transactions A de la Royal Society Publishing "The future of mathematical cosmology (part 1)", collectionné et édité par le Prof. Spiros Cotsakis et le Prof. Alexander Yefremov

La Royal Society Publishing a récemment publié un numéro spécial de Philosophical Transactions A, titré "The future of mathematical cosmology (part 1)" collectionné et édité par le Prof. Spiros Cotsakis et le Prof. Alexander P. Yefremov. Voici ci-dessous le résumé:
What are the main achievements in theoretical cosmology in the past 100 years? What is its present status and future prospects? What do we know about the big bang, dark energy, the future of the universe, the shape of spacetime, the multiverse, and the quantum nature of the cosmos? Mathematical cosmology was born in 1917 when Albert Einstein showed us how to build entire universes consistent with the laws of physics. Since then, it has developed into a fascinating field providing explanations for the new data and observations. This theme issue is the first devoted solely to the intricate nature of the universe, and provides a clear outline for future developments in this fundamental area of modern science.

Les articles peuvent être consultés directement au suivant lien: http://www.bit.ly/TransA-2222



12. Visites scientifiques auprès d'ICRANet

• Prof. Soroush Shakeri (Isfahan University of Technology, Iran), 2 Juillet - 17 Aout 2022
• Prof. Massimo Della Valle (Observatoire astronomique de Capodimonte, Italie), 6 - 9 Juillet 2022
• Prof. Carlos Raul Arguelles (UNLP Argentin), 6 - 20 Juillet 2022
• Prof. Yerlan Aimuratov (Fesenkov Astrophysical Institute et Al-Farabi Kazakh National University), 11 Juin - 31 Juillet 2022
• Tursynbek Yernazarov (Al-Farabi Kazakh National University), 23 Juin - 9 Septembre 2022
• Prof. Behzad Eslam Panah (Université de Mazandaran, Iran), 1 - 25 Septembre 2022
• Prof. Sergio Torres (Centro Internacional de Fisica, Bogotà, Colombie), 13 - 16 Septembre 2022

Prof. Soroush Shakeri Prof. Massimo Della Valle Prof. Carlos Arguelles Prof. Yerlan Aimuratov Tursynbek Yernazarov Prof. Behzad Eslam Panah Prof. Sergio Torres


Pendant leur visite, ils ont eu l'opportunité de discuter de leur travaux de recherché et d'avoir des intéressants échanges d'opinion avec les autres chercheurs ICRANet de toutes les parties du monde.



13. Publications récentes

F. Rastegarnia, R. Moradi, J. A. Rueda, R. Ruffini, Liang Li, S. Eslamzadeh, Y. Wang & S. S. Xue, The structure of the ultrarelativistic prompt emission phase and the properties of the black hole in GRB 180720B, published on September 2, 2022 in the European Physical Journal C, volume 82, article number 778.
In analogy with GRB 190114C, we here analyze the ultrarelativistic prompt emission (UPE) of GRB 180720B observed in the rest-frame time interval trf=4.84-10.89 s by Fermi-GBM. We reveal the UPE hierarchical structure from the time-resolved spectral analysis performed in time sub-intervals: the spectrum in each shorter time interval is always fitted by a composite blackbody plus cutoff power-law model. We explain this structure with the inner engine of binary-driven hypernova (BdHN) model operating in a quantum electrodynamics (QED) regime. In this regime, the electric field induced by the gravitomagnetic interaction of the newborn Kerr BH with the surrounding magnetic field is overcritical, i.e., E ≥ Ec, where Ec=m2e3/(eā„). The overcritical field polarizes the vacuum leading to an e+ e pair plasma that loads baryons from the surroundings during its expansion. We calculate the dynamics of the self-acceleration of the pair-electromagnetic-baryon (PEMB) pulses to their point of transparency. We characterize the quantum vacuum polarization process in the sequences of decreasing time bins of the UPE by determining the radiation timescale, Lorentz factors, and transparency radius of the PEMB pulses. We also estimate the strength of the surrounding magnetic field ∼1014 G, and obtain a lower limit to the BH mass, M=2.4 MāŠ™, and correspondingly an upper limit to the spin, α=0.6, from the conditions that the UPE is powered by the Kerr BH extractable energy and its mass is bound from below by the NS critical mass.
DOI: https://doi.org/10.1140/epjc/s10052-022-10750-x


Wang, Yu; Rueda, J. A.; Ruffini, R.; Moradi, R.; Li, Liang; Aimuratov, Y.; Rastegarnia, F.; Eslamzadeh, S.; Sahakyan, N.; Zheng, Yunlong, GRB 190829A-A Showcase of Binary Late Evolution, published on September 14, 2022 in The Astrophysical Journal, Volume 936, Issue 2, id.190.
GRB 190829A is the fourth-closest gamma-ray burst to date (z = 0.0785). Owing to its wide range of radio, optical, X-ray, and very-high-energy observations by HESS, it has become an essential new source that has been examined by various models with complementary approaches. Here, we show in GRB 190829A that the double prompt pulses and the three multiwavelength afterglows are consistent with the type II binary-driven hypernova model. The progenitor is a binary composed of a carbon-oxygen (CO) star and a neutron star (NS) companion. The gravitational collapse of the iron core of the CO star produces a supernova (SN) explosion and leaves behind a new NS (νNS) at its center. The accretion of the SN ejecta onto the NS companion and onto the νNS via matter fallback spins up the NSs and produces the double-peak prompt emission. The synchrotron emission from the expanding SN ejecta, with energy injection from the rapidly spinning νNS and its subsequent spindown, leads to the afterglow in the radio, optical, and X-ray bands. We model the sequence of physical and related radiation processes in BdHNe, and focus on individuating the binary properties that play the relevant roles.
DOI: https://doi.org/10.3847/1538-4357/ac7da3


Becerra, L. M.; Moradi, R.; Rueda, J. A.; Ruffini, R.; Wang, Y, The first minutes of a binary-driven hypernova, accepted for publication on September 21, 2022 in Physical Review D.
We simulate the first minutes of the evolution of a binary-driven hypernova (BdHN) event, with a special focus on the associated accretion processes of supernova (SN) ejecta onto the newborn neutron star (νNS) and the NS companion. We calculate the rotational evolution of the νNS and the NS under the torques exerted by the accreted matter and the magnetic field. We take into account general relativistic effects and use realistic hypercritical accretion rates obtained from three-dimensional smoothed-particle-hydrodynamics (SPH) numerical simulations of the BdHN for a variety of orbital periods. We show that the rotation power of the νNS has a unique double-peak structure while that of the NS has a single peak. These peaks are of comparable intensity and can occur very close in time or even simultaneously depending on the orbital period and the initial angular momentum of the stars. We outline the consequences of the above features in the early emission and their consequent observation in long gamma-ray bursts (GRBs).
ArXiv: https://arxiv.org/abs/2208.03069


Rueda, J. A.; Ruffini, R.; Li, L.; Moradi, R.; Rodriguez, J. F.; Wang, Y., Evidence for the transition of a Jacobi ellipsoid into a Maclaurin spheroid in gamma-ray bursts, accepted for publication on September 21, 2022 in Physical Review D.
In the binary-driven hypernova (BdHN) scenario, long gamma-ray bursts (GRBs) originate in a cataclysmic event that occurs in a binary system composed of a carbon-oxygen (CO) star and a neutron star (NS) companion in close orbit. The collapse of the CO star generates at its center a newborn NS (νNS), and a supernova (SN) explosion. Matter from the ejecta is accreted both onto the νNS because of fallback and onto the NS companion, leading to the collapse of the latter into a black hole (BH). Each of the ingredients of the above system leads to observable emission episodes in a GRB. In particular, the νNS is expected to show up (hereafter νNS-rise) in the early GRB emission, nearly contemporary or superimposed to the ultrarelativistic prompt emission (UPE) phase, but with a different spectral signature. Following the νNS-rise, the νNS powers the afterglow emission by injecting energy into the expanding ejecta leading to synchrotron radiation. We here show that the νNS-rise and the subsequent afterglow emission in both systems, GRB 180720B and GRB 190114C, are powered by the release of rotational energy of a Maclaurin spheroid, starting from the bifurcation point to the Jacobi ellipsoid sequence. This implies that the νNS evolves from a triaxial Jacobi configuration, prior to the νNS-rise, into the axially symmetric Maclaurin configuration observed in the GRB. The triaxial νNS configuration is short-lived (less than a second) due to a copious emission of gravitational waves, before the GRB emission, and it could be in principle detected for sources located at distances closer than 100 Mpc. This appears to be the sole process of emission of gravitational waves in long GRBs.
ArXiv: https://arxiv.org/abs/2203.16876


G. Vereshchagin, M. Prakapenia, Kinetics of Degenerate Electron-Positron Plasmas, published on September 9, 2022 in Universe.
Relativistic plasma can be formed in strong electromagnetic or gravitational fields. Such conditions exist in compact astrophysical objects, such as white dwarfs and neutron stars, as well as in accretion discs around neutron stars and black holes. Relativistic plasma may also be produced in the laboratory during interactions of ultra-intense lasers with solid targets or laser beams between themselves. The process of thermalization in relativistic plasma can be affected by quantum degeneracy, as reaction rates are either suppressed by Pauli blocking or intensified by Bose enhancement. In addition, specific quantum phenomena, such as Bose-Einstein condensation, may occur in such a plasma. In this review, the process of plasma thermalization is discussed and illustrated with several examples. The conditions for quantum condensation of photons are formulated. Similarly, the conditions for thermalization delay due to the quantum degeneracy of fermions are analyzed. Finally, the process of formation of such relativistic plasma originating from an overcritical electric field is discussed. All these results are relevant for relativistic astrophysics as well as for laboratory experiments with ultra-intense lasers.
DOI: https://www.mdpi.com/2218-1997/8/9/473


J. Sedaghat, S.M. Zebarjad, G.H.Bordbar, B. Eslam Panah, R. Moradi, Is the remnant of GW190425 a strange quark star?, published on August 18, 2022 in Physics Letters B, Volume 833, 10 October 2022, 137388.
This study investigates the effects of different QCD models on the structure of strange quark stars (SQS). In these models, the running coupling constant has a finite value in the infrared region of energy. By imposing some constraints on the strange quark matter (SQM) and exploiting the analytic and background perturbation theories, the equations of states for the SQM are obtained. Then, the properties of SQSs in general relativity are evaluated. By using component masses of GW190425 [1] as well as some conversion relations between the baryonic mass and the gravitational mass, the remnant mass of GW190425 is obtained. Our results for the maximum gravitational mass of SQS are then compared with the remnant mass of GW190425. The results indicate that the obtained maximum gravitational masses are comparable to the remnant mass of GW190425. Therefore, it is proposed that the remnant mass of GW190425 might be a SQS.
DOI: https://doi.org/10.1016/j.physletb.2022.137388
 
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