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Newsletter English July/August/September 2022 Print E-mail


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ICRANet Newsletter



ICRANet Newsletter
July/August/September 2022



SUMMARY
1. ICRA - ICRANet press release "GRB 190829A - A Showcase of Binary Late Evolution"
2. The 6th Bego Rencontre Summer School, July 4 - 14, 2022, Nice and online
3. Announcement of the 5th Zeldovich meeting, June 12 - 17, 2023, Yerevan (Armenia)
4. The European Researchers' Night, September 30, 2022, online event
5. New collaboration agreements signed by ICRANet
6. ICRANet participation at the IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics, September 5-9, 2022, Guatemala and online
7. ICRANet participation at the Bad Honnef Physics School, September 5-9, 2022, Bad Honnef (Germany)
8. ICRANet participation at the 31st Texas Symposium on Relativistic Astrophysics, September 12-16, 2022, Prague (Czech Republic)
9. Prof. Ruffini participation at the event "The cultural diplomacy between Italy and America", July 7, 2022, Italian Senate in Rome (Italy)
10. Prof. Massimo Della Valle, President of the ICRANet Scientific Committee, appointed correspondent member of the Academy of Lincei
11. Royal Society Publishing special issue of Philosophical Transactions A "The future of mathematical cosmology (part 1)", compiled and edited by Prof. Spiros Cotsakis and Prof. Alexander Yefremov
12. Scientific visits to ICRANet
13. Recent publications


1. ICRA - ICRANet press release "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.

References:
Abdalla, H., Adam, R., Aharonian, F., et al. 2019, Nature, 575, 464, doi: 10.1038/s41586-019-1743-9
Becerra, L., Bianco, C. L., Fryer, C. L., Rueda, J. A., & Ruffini, R. 2016, ApJ, 833, 107, doi: 10.3847/1538-4357/833/1/107
Becerra, L., Cipolletta, F., Fryer, C. L., Rueda, J. A., & Ruffini, R. 2015, ApJ, 812, 100, doi: 10.1088/0004-637X/812/2/100
Becerra, L., Ellinger, C. L., Fryer, C. L., Rueda, J. A., & Ruffini, R. 2019, ApJ, 871, 14, doi: 10.3847/1538-4357/aaf6b3
Fishman, G. J., & Meegan, C. A. 1995, ARA&A, 33, 415, doi: 10.1146/annurev.aa.33.090195.002215
Fryer, C. L., Rueda, J. A., & Ruffini, R. 2014, ApJL, 793, L36, doi: 10.1088/2041-8205/793/2/L36
MAGIC Collaboration, Acciari, V. A., Ansoldi, S., et al. 2019, Nature, 575, 455, doi: 10.1038/s41586-019-1750-x
Meszaros, P. 2002, ARA&A, 40, 137, doi: 10.1146/annurev.astro.40.060401.093821
Moradi, R., Rueda, J. A., Ruffini, R., & Wang, Y. 2021, A&A, 649, A75, doi: 10.1051/0004-6361/201937135
Piran, T. 2000, PhR, 333, 529, doi: 10.1016/S0370-1573(00)00036-3
Rueda, J. A., & Ruffini, R. 2012, ApJL, 758, L7, doi: 10.1088/2041-8205/758/1/L7
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Rueda, J. A., Ruffini, R., Karlica, M., Moradi, R., & Wang, Y. 2020, ApJ, 893, 148, doi: 10.3847/1538-4357/ab80b9
Rueda, J. A., Ruffini, R., Moradi, R., & Wang, Y. 2021, International Journal of Modern Physics D, 30, 2130007, doi: 10.1142/S021827182130007X
Rueda, J. A., Ruffini, R., & Wang, Y. 2019, Universe, 5, 110, doi: 10.3390/universe5050110
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Ruffini, R., Becerra, L., Bianco, C. L., et al. 2018c, ApJ, 869, 151, doi: 10.3847/1538-4357/aaee68
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2. The 6th Bego Rencontre Summer School, July 4 - 14, 2022, Nice and online

The 6th Bego Rencontre Summer School has been held from July 4 to 14, 2022 as an hybrid event, both in person at the ICRANet Seat Villa Ratti in Nice (France) and online.
The School aimed to discuss recent developments in the theory and observations of gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and dark matter (DM).

Some relevant topics discussed about GRBs and AGNs have been:
• the energy extraction process from rotating black holes (BHs) in the inner engine of the high-energy (e.g. GeV) emission of long GRBs and AGNs. Special attention is given to inner engines comprising a Kerr BH immersed in a magnetic field and ionized plasma. Recent developments on the topic, especially the problem of field screening, electric discharge, radiation properties, black hole physics, magneto hydrodynamics, and the maximum electric charge allowed in the inner engines;
• the recent progress in GRB theory, for instance in the binary-driven hypernova (BdHN) model. This includes the physical explanation of the ultra relativistic prompt emission (UPE) phase in the MeV regime, the afterglow emission in the X-rays, optical, and radio wavelengths, and the GeV emission;
• the Supernova associated with GRBs and the role of the supernova explosion in the entire emission of a long GRB;
• GRBs at high-redshift and GRB-cosmology;
• the emission of GRB cocoons (observations);
• the emission of M87* (theory and observations).

Some relevant topics discussed about dark matter have been:
• Fermionic and bosonic dark matter: microphysics;
• Fermionic and bosonic dark matter: macrophysics;
• Recent developments in the description of the Galactic center (Sgr A*) as a core of dark matter;
• Latest astrometric observations of stars orbiting Sgr A* and observational constraints on the nature of Sgr A*;
• Latest news on the baryonic content in galaxies;
• Strong gravitational lensing;
• Dark matter in early cosmology, cosmological simulations and dark matter halo formation.


More than 90 participants from 19 different countries joined the conference, and several lecture have been presented by 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 and Bing Zhang.
The meeting webpage is available at the following link: https://indico.icranet.org/event/4/
The recordings of the different sessions are now available on the ICRANet YouTube channel, at the following link: https://www.youtube.com/channel/UCU19scWRGvlIiKBcN1QXCRQ



3. Announcement of the 5th Zeldovich meeting, June 12 - 17, 2023, Yerevan (Armenia)


We are happy to inform you that ICRANet is organizing the 5th Zeldovich meeting, an international conference in honor of Ya. B. Zeldovich, which will be held in Yerevan (Armenia) on June 12-17, 2023. This conference will follow a series of very successful international conferences in honor of Ya. B. Zeldovich, respectively held in Minsk in 2009, 2014, 2018 and online in 2020.
Exceptionally wide research interests of Ya. B. Zeldovich, ranging from chemical physics, elementary particle and nuclear physics to astrophysics and cosmology, provide the topics to be covered during the conference:
• multimessanger astrophysics;
• early universe, large scale structure, cosmic microwave background;
• neutron stars, black holes, gamma-ray bursts, supernovae, hypernovae;
• gravitational waves;
• quantum and gravity.

Traditionally, among the invited speakers, there will be members of the world-famous scientific school in astrophysics and cosmology, founded by Ya. B. Zeldovich.
The registration to this meeting has just started.
All the information on this event are posted on its official website: http://www.icranet.org/zeldovich5



4. The European Researchers' Night, September 30, 2022, online event

On the occasion of the European Researchers' Night 2022, ICRANet, in collaboration with Prof. Costantino Sigismondi (ICRANet collaborator), organized an online event, in order to create a nice occasion for discussion among researchers and students. This event attracted a lot of people, as every year, and offered to the participants a unique opportunity to take part in science activities aiming to showcase both the fascination of research as a career and its significant societal impact.
The online meeting was held on Friday September 30, 2044, starting from 4:30 PM. After the opening remarks, Prof. Remo Ruffini, Director of ICRANet, presented a talk on the Supernovae and the recent development in the field of Relativistic astrophysics. After him, Prof. Liang Li and Prof. Wang Yu, both ICRANet Faculty Professors, presented 2 lectures respectively on the Supernovae's progenitors and the numerical models. Then Prof. Costantino Sigismondi spoke about Antares and the stellar variability, about the measurement of the Earth radius, as well as about ICRANet and high school. He also discussed with participants about the present and future perspectives of science and about Supernovae and binary Stars.


Fig. 3: 456 observations of Antares in 2014.

He explained that the majority of the stars are in multiple systems and the interactions among their components can determine the trigger for the explosion of a Supernova, the most luminous phenomenon in the Universe. The binary Stars' systems and the Supernovae's progenitors are 2 topics which attracted theoretical studies for a long time. Sophisticated numerical models, based on the General Relativity equations, necessary when the mass and the dimension of the stellar object lead the material to overcome the density of the atomic nucleus, allow to represent today the observational data with high accuracy. At the same time, the observational data are enhanced by multi-spectral information received by a constantly increasing number of instruments, devoted to the detection of the sky in its different wavelengths, both from Earth and from Space: this is what Prof. Li and Wang presented.


Fig. 4: Geometrical schema of the method of Eratostene for the measurement of the Earth radius (Federico Battistol, Liceo Scarpa di Motta di Livenza (TV)

The observation of the stellar variability of the red and binary supergiant Antares, registered in the last 8 years, has been the main topics presented and commented by Prof. Sigismondi: ranges of few hundredth of magnitude are visible at naked eye, provided that it should be corrected, for the atmospheric extinction, the comparison with stars similarly bright, which are distant from Antares several tens of grades. The observations made by the satellite SOHO complete the framework. The concept of magnitude and the logarithmic scale of luminosities, at the base of a correct interpretation of the astrophysical phenomena, have been also presented to the students.



5. New collaboration agreements signed by ICRANet

New collaboration agreement between ICRANet and the Fesenkov Astrophysical Institute (Kazakhstan), August 5, 2022


On August 5, 2022 ICRANet has signed a new Cooperation protocol with the Fesenkov Astrophysical Institute in Kazakhstan. The Cooperation Protocol has been signed by Prof. Chingis Omarov (Director of the Fesenkov Astrophysical Institute), by Prof. Yerlan Aimuratov (Fesenkov Astrophysical Institute), by Prof. Remo Ruffini (Director of ICRANet) and by Prof. Jorge Rueda (ICRANet Faculty Professor).
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=1451


New collaboration agreement between ICRANet and AEROSPACIFIC (Colombia), September 1, 2022


On September 1, 2022 ICRANet has signed a new Cooperation protocol with the AEROSPACIFIC cluster in Colombia. The Cooperation Protocol has been signed by Dr Cesar Augusto Rodriguez Adaim (President of AEROSPACIFIC) and by Prof. Remo Ruffini (Director of ICRANet).
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=1452


New collaboration agreement between ICRANet and the Iranian National Observatory (INO), September 8, 2022


On September 8, 2022 ICRANet has signed a new Cooperation protocol with the Iranian National Observatory (INO) in Iran. The Cooperation Protocol has been signed by Prof. Habib Khosroshahi (Director of INO) and by Prof. Remo Ruffini (Director of ICRANet). 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/documents/agreementICRANet-INO.pdf


New collaboration agreement between ICRANet and the Indian Center for Space Physics, September 21, 2022


On September 21, 2022 ICRANet has signed a new Cooperation protocol with the Indian Center for Space Physics in India. The Cooperation Protocol has been signed by Prof. Sandip Chakrabarti (Director of the Indian Center for Space Physics) and by Prof. Remo Ruffini (Director of ICRANet).
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=1453



6. ICRANet participation at the IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics, September 5-9, 2022, Guatemala and online

From September 5 to 9, 2022 Professor Remo Ruffini, Director of ICRANet has been invited to deliver a plenary lecture on the occasion of the meeting "IWARA 2022. The 10th international workshop on Astronomy and Relativistic Astrophysics". This meeting was the tenth in a series of meetings, gathering scientists working on astroparticle physics, cosmology, gravitation, nuclear physics, and related fields. The event has been held in an hybrid format, both in person in Guatemala and online.


On Monday, September 5, Prof. Ruffini presented online a lecture titled "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs", here below the abstract:
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.

The proceedings of the meeting will be published by the Astronomische Nachrichten.
For the website of the meeting: https://indico.cern.ch/event/921532/



7. ICRANet participation at the Bad Honnef Physics School, September 5-9, 2022, Bad Honnef (Germany)

From September 5 to 9, 2022 Professor Remo Ruffini, Director of ICRANet has been invited to present a lecture on the occasion of the Bad Honnef Physics School in Bad Honnef (Germany), together with Prof. Liang Li and Prof. Rahim Moradi (both ICRANet Faculty Professors).
This School was dedicated to the observational, theoretical and also epistemological aspects of Black Hole physics and covered the following topics: tentative definition of a Black Hole, observational evidence and possible alternative explanations for Black Holes, formation of Black Holes, global structure and causality of Black Hole space times, rigorous definition of a Black Hole, singularity theorems, uniqueness of Black Hole solutions (no-hair theorems), stability properties, Black Holes in generalized theories of gravity, modeling Black Holes in analog-gravity models, quantum fields in Black Hole-space times, Black Holes in quantum gravity proper, epistemological and philosophical aspects of Black Holes. The meeting has been co-organized by Prof. Dr. Domenico Giulini (ITP, University of Hannover & ZARM, University of Bremen), Dr. Eva Hackmann (ZARM, University of Bremen) and Prof. Dr. Claus Lämmerzahl (ZARM, University of Bremen).
On Thursday, September 8, Prof. Ruffini, followed by Prof. Li and Prof. Moradi, presented a lecture titled "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs". Here below the abstract: 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.

For the website of the School: https://www.dpg-physik.de/veranstaltungen/2022/black-holes



8. ICRANet participation at the 31st Texas Symposium on Relativistic Astrophysics, September 12-16, 2022, Prague (Czech Republic)

From September 12 to 16, 2022 Professor Remo Ruffini, Director of ICRANet has been invited to present a lecture on the occasion of 31st Texas Symposium on Relativistic Astrophysics, held in Prague (Czech Republic). Together with him, also Prof. Rahim Moradi and Prof. Yu Wang (both ICRANet Faculty Professors) have been invited to present a lecture on that occasion.


Fig. 5: group photo of all the participants to the 31st Texas Symposium on Relativistic Astrophysics in Prague.

Since 1963, the Texas Symposium has been one of the major meetings on Relativistic Astrophysics. Traditionally, it moves around the globe and takes place in different cities every 2 years. The main topics addressed during the conference have been Gravity (Classical, Numerical, Quantum, Modified, Tests), Relativity (Black Holes, Neutron Stars, Accretion, Jets), Multimessanger (Cosmic Rays, Neutrinos, Gamma Rays, X Rays, Gravitational Waves), Cosmology (Cosmic Microwave Background, Reionization, Early Universe, Large Scale Structure, Dark Matter), as well as special sessions on the Event Horizon Telescope, GRAVITY, X-ray Polarimetry and the James Webb Space Telescope.

On Wednesday, September 14, Prof. Ruffini presented a lecture titled "The role of a standard family of Ic Supernovae in BdHN I, BDHN II and BDHN III GRBs". Here below the abstract:


Fig. 6: Prof. Remo Ruffini presenting his lecture at the 31st Texas Symposium on Relativistic Astrophysics in Prague, September 14, 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).

On the same day, Prof. Yu Wang (ICRANet Faculty Professor) presented a lecture titled "GRB 190829A - A Showcase of Binary Late Evolution". Here below the abstract:


Fig. 7: Prof. Yu Wang presenting his lecture at the 31st Texas Symposium on Relativistic Astrophysics in Prague, September 14, 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.

On Thursday, September 15, 2022, Prof. Rahim Moradi presented a lecture titled "Nature of the ultra-relativistic prompt emission (UPE) phase in GRB 180720B and GRB 190114C". Here below the abstract:


Fig. 8: Prof. Rahim Moradi presenting his lecture at the 31st Texas Symposium on Relativistic Astrophysics in Prague, September 15, 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.

For the website of the meeting: https://texas2021.org/



9. Prof. Ruffini participation at the event "The cultural diplomacy between Italy and America", July 7, 2022, Italian Senate in Rome (Italy)

On July 7, 2022 Prof. Ruffini has been invited to participate to the event "The cultural diplomacy between Italy and America", held in the sala Capitolare of the Italian Senate in Rome (Italy).
The conference has been organized by the Italian Senator Pier Ferdinando Casini, in collaboration with the American think tank Renaissance Evolution, aiming at the promotion of culture as the engine for dialogue, harmony and wealth among people and countries. Several eminent personalities joined the conference and took the floor, such as the Italian Ministry of Culture Dario Franceschini, the Archbishop Vincenzo Paglia, the Italian Ambassador in Santo Domingo Stefano Queirolos Palmas, the Secretary general of the International Organization Italian- Latin- American Antonella Cavallari, as well as the expert in geopolitics Michele Pavan and the political analyst Tim Phillips.
For the video of the event: https://www.youtube.com/watch?v=xTDPZFOTuHI



10. Prof. Massimo Della Valle, President of the ICRANet Scientific Committee, appointed correspondent member of the Academy of Lincei

It is our pleasure to announce that Prof. Massimo Della Valle, Director of the Capodimonte Astronomical Observatory and President of the ICRANet Scientific Committee, has been appointed correspondent member of the Academy of Lincei on July 28, 2022, for the division of Physical Sciences.
For the news on the Academy of Lincei website: https://www.lincei.it/it/news/nuovi-soci-2022



11. Royal Society Publishing special issue of Philosophical Transactions A "The future of mathematical cosmology (part 1)", compiled and edited by Prof. Spiros Cotsakis and Prof. Alexander Yefremov

Royal Society Publishing has recently published a special issue of Philosophical Transactions A entitled The future of mathematical cosmology (part 1), compiled and edited by Spiros Cotsakis and Alexander P. Yefremov. Here below the abstract:
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.

The articles can be accessed directly at the following link: http://www.bit.ly/TransA-2222



12. Scientific visits to ICRANet

• Prof. Soroush Shakeri (Isfahan University of Technology, Iran), July 2 - August 17, 2022
• Prof. Massimo Della Valle (Osservatorio di Capodimonte - Italy), July 6 - 9, 2022
• Prof. Carlos Raul Arguelles (UNLP Argentina), July 6 - 20, 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 9, 2022
• Prof. Behzad Eslam Panah (University of Mazandaran, Iran), September 1 - 25, 2022
• Prof. Sergio Torres (Centro Internacional de Fisica, Bogotà, Colombia), September 13 - 16, 2022

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


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

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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