Conveners
Searches for Galactic astrophysical sources - 2
- Silvia Celli (Istituto Nazionale di Fisica Nucleare)
Massive stars are rarely born alone and are generally found in binary or triple systems as part of star clusters and associations. The stars emit copious thermal radiation from radio to X-rays, and wind-wind collisions enable particle acceleration with associated broadband non-thermal emission. In this talk I will review some of the astrophysics of binary star systems and young massive...
Supernova remnants (SNRs) are likely to be significant sources of cosmic rays (CRs) up to the knee of the CR spectrum. They produce gamma rays in the very-high-energy (VHE) range. About a dozen SNRs emitting VHE gamma rays have been detected by current instruments and it is expected that many more will be detected by future instruments.
However, the details of particle acceleration at SNRs,...
Massive Star Clusters (SCs) have been proposed as additional contributors to Galactic Cosmic rays (CRs), to overcome the limitations of supernova remnants (SNR) to reach the highest energy end of the CR spectrum. Thanks to fast mass losses due to the collective stellar winds, the environment around SCs is potentially suitable for particle acceleration up to PeV energies and the energetics is...
Since the discovery of TeV halos around the Geminga and B0656+14 pulsars by the HAWC experiment in 2017, many theoretical efforts have been dedicated to understanding this source class. Indeed, assuming that they are probing the environment outside their parent supernova remnant (SNR), the gamma-ray emission hints at a confinement of high energy particles that challenges our current...
RS Ophiuchi is a recurrent nova which explodes on average every 15 years. These explosions result in nova shocks from which non-thermal particles and radiation are produced. In fact, the most recent outburst of RS Ophiuchi in 2021 has been observed by a few different gamma-ray instruments including FERMI-LAT, HESS and MAGIC. Interestingly, the highest TeV gamma rays are only detected about two...
The fourth catalag of Fermi Large Area Telescope (LAT) consists of
2157 unassociated gamma ray sources. These are gamma-ray sources whose
counterparts in other wavelengths (such as radio, X-ray, or optical) have not
been identified. Their nature remains a mystery making them fascinating
objects to study. The Direct Search Analysis (DSA) , a novel method also
utilised to analyse continuous...
Many star-forming regions have been detected in the gamma-ray band in recent years and are gaining a lot of interest as possible contributors to the Galactic hadronic cosmic-ray sea. However, not much emphasis has been put so far in the contribution of cosmic-ray electrons to their gamma-ray emission.
In our presentation we develop a novel approach to investigate the origin of the gamma-ray...
