Conveners
Parallel 10: GRBs and Fast Transients- I
- Andreas von Kienlin (MPE)
The origin of gamma-ray bursts (GRBs) is still mysterious. We believe that binary neutron star (BNS) mergers produce short GRBs, while long GRBs are associated to the collapse of massive stars.
This GRB dichotomy, based on the duration of the prompt pulse, was recently challenged by the detection of the bright and relatively close (z=0.076) GRB 211211A. Despite its long duration (~30 s),...
LIGO, Virgo, and KAGRA will begin the fourth gravitational wave observing run in March 2023. Gamma-ray burst identification and localization are key to multimessenger studies with neutron star mergers, with scientific results spanning from fundamental physics to ultrarelativistic particle acceleration. We will detail the partnership and plans of the gravitational wave collaborations with Fermi...
Gamma-ray bursts (GRBs) emit cosmic high-energy gamma rays over a short period of time and the origin of gamma rays is still under debate. Recent gamma-ray observations in the GeV and TeV bands by Fermi and MAGIC revealed that some of the high-energy gamma rays are thought to originate from the forward shock of GRB jets. However, early-stage bright gamma-ray emissions are still poorly...
The origin of the large-scale magnetic fields in the Universe is one of the long-standing problems in cosmology. To discriminate among the different explanations it is crucial to measure the intergalactic magnetic field (IGMF) in the voids among the galaxies. Gamma-rays coming from extragalactic sources can be used to constrain the IGMF due to their interaction with the intergalactic medium....
Gamma-ray bursts (GRBs) are known to have the most relativistic jets, with initial expansion Lorentz factors of 100< Gamma_i <1000. Many of these objects have a plateau in their early X-ray light curves (up to thousands of seconds). In this phase, the X-ray flux decreases much slower than theoretically expected which has puzzled the community for many years. Here, we show that the observed...
Magnetars are a type of neutron star characterized by strong (10^14 − 10^15 G), short-lived (∼ 10^4 yr) magnetic fields. They display a range of high energy electromagnetic activity. The brightest and most energetic of these events, with Eiso ≈ 10^44 − 10^46 erg, is the magnetar giant flare (MGF). To date only 7 such events have been discovered, 3 of which occurred in our galactic...
Fast radio bursts (FRBs) are one of the most exciting new mysteries of astrophysics. Their origin is still unknown, but recent observations seem to link them to soft gamma repeaters and, in particular, to magnetar giant flares (MGFs). The recent detection of a MGF at GeV energies by the Fermi Large Area Telescope (LAT) motivated the search for GeV counterparts to the >1000 currently known...
