Marco Tavani

Time resolved GRB spectroscopy

We present the main results of a study of time-resolved spectra of 43 intense GRBs detected by BATSE. We considered the 4-parameter Band model and the Optically Thin Synchrotron Shock model (OTSSM). We find that the large majority of time-resolved spectra of GRBs are in remarkable agreement with the OTSSM. However, about 15% of initial GRB pulses show an apparent low-energy photon suppression. This phenomenon indicates that complex radiative conditions modifying optically thin emission may occur during the initial phases of some GRBs.

AGILE hunts gravitational waves counterparts

After the breakthrough discovery of gravitational waves by the LIGO-Virgo collaboration in 2015, the quest for electromagnetic counterparts to extreme gravitational events is now open. We report the results of an extensive search through AGILE data for a high-energy counterpart to the first gravitational wave event ever detected: GW150914. The Italian Space Agency satellite AGILE devoted to gamma-ray astrophysics is operating nominally since its launch on April 23, 2007, and it is continuosly monitoring the sky in a spinning observation mode. With the potential of covering ∼80% of the entire sky with its gamma-ray instrument more than 100 times a day, AGILE is currently at the forefront in the hunt for electromagnetic counterparts of gravitational waves. Even though a gamma-ray counterpart of the GW150914 event was not detected, the prospects for future AGILE observations of GW sources are shown to be very promising

Measuring The Variability Of Gamma-Ray Sources With AGILE

Variability in the gamma‐ray flux above 100 MeV at various time scales is one of the primary characteristics of the sources detected by EGRET, both allowing the identification of individual sources and constraining the unidentified source classes. We present a detailed simulation of the capacity of AGILE to characterize the variability of gamma‐ray sources, discussing the implications for source population studies.