Seminario A.Tsvetkova

Il giorno 20 dicembre alle ore 20 presso l'aula 412 Anastasia Tsvetkova (Max Planck Institure for extraterrestrial physics, Munich) terra' un seminario dal titolo:

Prospects for cosmological and population GRB studies with Konus-Wind

Abstract

Gamma-ray bursts (GRBs) with measured redshifts (z) may provide essential insights into cosmology and GRB population. We present the results of a systematic study of temporal and spectral parameters, as well as energetics of GRBs with known z detected by Konus-Wind (KW). The first part of this work comprises 171 events detected in the triggered mode from 1997 February to 2019 March. The second part includes the bursts detected simultaneously by KW in the waiting mode and by the Swift/BAT (BAT) telescope during the period from 2005 January to the end of 2018. By taking advantage of the high sensitivity of BAT and the wide spectral band of KW, we were able to constrain the peak spectral energies, the broadband energy fluences, and the peak fluxes for the joint KW–BAT sample of 167 weak, relatively soft GRBs. Thus, the whole sample of KW GRBs with known z comprises 338 events, which makes it the largest set of cosmological GRBs studied to date over a broad energy band. 
Based on the GRB redshifts, which span the range 0.04 < z < 9.4, we estimate the rest frame isotropic-equivalent energy and peak luminosity. For 46 GRBs with reasonably constrained jet breaks, we provide the collimation-corrected values of the energetics. With the full KW sample, accounting for the instrumental bias, we explore GRB rest-frame properties, including the hardness–intensity correlations, GRB luminosity evolution, luminosity and isotropic-energy functions, and the evolution of the GRB formation rate.