| Weekly Seminars for November 2015 |
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Monday November 9th,
2015 - 2,30 pm
Aula Conversi (Physics Dept., Marconi Building, 1st Floor)
Joint Astrophysics Seminar - Department of Physics and ICRA
Speaker: Dr. Omar Tibolla
Institution: Mesoamerican Centre for Theoretical Physics (MCTP), Mexico Title: The origin of Cosmic Rays: the possible role of Unidentified High Energy sources
Abstract:
The riddle of the origin of Cosmic Rays is open since more than one century.
Gamma ray observations above 100 MeV reveal the sites of cosmic ray acceleration and recently we got the experimental proof of hadronic acceleration in Supernovae Remnants, however new questions rised and no final answer has been provided so far. In the last years the knowledge in this field of research widely increased, however almost 50% of the TeV (> 10^{12} eV) Galactic sources are still unidentified; at GeV (> 10^9 eV) energies, 67% of EGRET sources were unidentified and also with the newer generation of gamma-ray satellites we have the same result: in fact, at low Galactic latitudes (b <10 deg), 62% of the Fermi LAT detected sources have no formal counterpart. Hence understanding the high energy unidentified sources will be a crucial brick in solving the whole riddle of Cosmic Rays origin. Several examples will be shown, underlining the importance of the so-called "dark sources". Both theoretical aspects (with particular emphasis to the so-called Ancient Pulsar Wind Nebulae scenario) and their observational proofs will be discussed.
N.B. - In the following link, you can find the official announcement on the Physics Department website: http://www.phys.uniroma1.it/fisica/sites/default/files/bollettini/bollettino09112015.pdf
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La Segreteria ICRA
c/o Dipartimento di Fisica
Sapienza Università di Roma
P.le A. Moro, 5 I - 00185 ROMA, Italy tel.: +39 06 4991 4 254 fax: +39 06 4454992 email: segreteria@icra.it
Thursday November 12th,
2015 - 12,00 pm
Sala Cassini (inside the headquarters of the Italian Space Agency in Tor Vergata)
ASI (Italian Space Agency) Seminar
Speaker: Prof. Paolo Giommi
Institution: Italian Space Agency - ASI Title: The Extragalactic multi-frequency multi-messenger sky
Abstract:
Our knowledge of the extragalactic sky is evolving very rapidly as new multi-frequency data is becoming available at ever-increasing rates.
This is particularly true in the high-energy domain (GeV and VHE-TeV gamma-ray bands) where space (AGILE and Fermi satellites) and ground-based observatories (Cherenkov telescopes) are discovering thousands of new sources. The possibile association of astronomical objects with cosmic "messengers" like neutrinos and Ultra High Energy Cosmic Rays (UHECRs) as detected by the current generation of cosmic-ray observatories like Auger and IceCube is pushing the exciting new frontier of multi-messenger astrophysics. In my seminar I will present recent results on the gamma-ray emission from extragalactic sources based on the latest Fermi-LAT catalogs (3FGL-3LAC and 2FHL) and on new large samples of multi-frequency selected gamma-ray and VHE emitting blazars (1WHSP and 2WHSP). I will also discuss some predictions for future observations with the upcoming Cherenkov Telescope Array (CTA) and the prospects for the opening of the multi-messenger window in astrophysics, including the possible contribution of blazars to the extragalactic Neutrino background.
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La Segreteria ICRA
c/o Dipartimento di Fisica
Sapienza Università di Roma
P.le A. Moro, 5 I - 00185 ROMA, Italy tel.: +39 06 4991 4 254 fax: +39 06 4454992 email: segreteria@icra.it
Thursday November 19th,
2015 - 3,30pm
ICRANet Pescara
ICRANet Seminar
Speaker: Prof. Maxim KHLOPOV
Institution: APC laboratory, Paris, France and National Research Nuclear University MEPHI, Moscow Russia Title: Primordial nonlinear structures in the Universe from particle physics beyond the Standard model
Abstract:
The pattern of particle symmetry breaking in the extensions of the Standard model can reflect in various macroscopic cosmological structures, created in very early Universe. The an example of a simple global U(1) symmetry, broken spotaneously and then manifestly such structures as: large scale correlations in the distribution of energy density of axion field oscillations in the cosmology of invisibble axion; clouds of massive primordial blck holes as possible pregalactic seeds for AGN formation and antimatter globular clusters in bbaryon asymmetric Universe will be discussed.
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ICRANet Secretariat
ICRANet
Piazza della Repubblica 10 65122 Pescara (PE) Italy tel.: +39 085 23054200 fax: +39 085 4219252 email: secretariat@icranet.org |