Conveners
Gravitational Waves and Gamma-ray Bursts: Parallel-1
- Andreas von Kienlin (MPE)
Observations of the gravitational-wave event GW190425 registered by the LIGO/Virgo detectors with the Anti-Coincidence Shield (ACS) of the gamma-ray spectrometer SPI aboard the INTEGRAL observatory are presented. This is only the second event of binary neutron star merging type (> 99% probability) after GW170817. A weak gamma-ray burst, GRB190425, consisting of two pulses in 0.5 and 5.9 s...
The joint observation of GW170817 and GRB170817A proved that binary neutron star (BNS) mergers are progenitors of short Gamma-ray Bursts (SGRB): this established a direct link between the still unsettled SGRB central engine and the outcome of BNS mergers, whose nature depends on the equation of state (EOS) and on the masses of the NSs. We propose a novel method to probe the central engine of...
It is known from theoretical models and the observation of GW170817 that short gamma ray bursts (SGRBs) can be emitted by the merger of two neutron stars. The outcome of this merger may produce a short-lived (~ 100 ms) hypermassive neutron star (HMNS) before collapsing to a black hole. If the SGRB is emitted during the HMNS phase, it may be modulated by oscillations of the HMNS, with expected...
Being discovered more than 40 years ago, gamma-ray bursts (GRBs) remain one of the mysterious astrophysical objects. In fact, the physics of relativistic jets formation, their composition, dissipation processes are still some of the biggest unknown in GRBs. The inability to establish the radiative processes shaping the observed prompt emission spectra does not allow us to make a big step...
At last, after more than 40 years from their discovery, the long-lasting tension between predictions and observations of GRBs spectra could be solved. We realized that the observed spectra can be produced by the synchrotron process from a distribution of electrons truncated at low energies. This low energy cut-off demands that electrons do not completely cool. Evidence for incomplete cooling...
Very high energy astrophysical sources show flaring and transient behaviour on different timescales, from fraction of seconds to years. These transient sources are usually observed and monitored over the whole electromagnetic spectrum. This contribution will outline the very high energy (VHE, $E>100$ GeV) transient search program operated by the MAGIC telescopes. In this context, Imaging...
