2021/04/21 by G. Ghirlanda, R. Salvaterra, M. Toffano +32
Engineering · Physics and Astronomy · #Afterglow #Astronomy and Astrophysical Research #CCD and CMOS Imaging Sensors #Collimated light #Ejecta #Gamma-ray burst #Gamma-ray bursts and supernovae #Redshift #Spectrometer #Stars #Synchrotron #Telescope #astro-ph.IM
paper · pdf · doi:10.1007/s10686-021-09763-3
Submitted to Experimental Astronomy
arxiv created 2021/04/21 · openalex created_date 2021/04/26 · openalex publication_date 2021/06/30 · arxiv updated 2021/07/07 · openalex updated_date 2026/08/05
Abstract Gamma-ray Bursts (GRBs) are the most powerful transients in the Universe, over–shining for a few seconds all other γ -ray sky sources. Their emission is produced within narrowly collimated relativistic jets launched after the core–collapse of massive stars or the merger of compact binaries. THESEUS will open a new window for the use of GRBs as cosmological tools by securing a statistically significant sample of high- z GRBs, as well as by providing a large number of GRBs at low–intermediate redshifts extending the current samples to low luminosities. The wide energy band and unprecedented sensitivity of the Soft X-ray Imager (SXI) and X-Gamma rays Imaging Spectrometer (XGIS) instruments provide us a new route to unveil the nature of the prompt emission. For the first time, a full characterisation of the prompt emission spectrum from 0.3 keV to 10 MeV with unprecedented large count statistics will be possible revealing the signatures of synchrotron emission. SXI spectra, extending down to 0.3 keV, will constrain the local metal absorption and, for the brightest events, the progenitors’ ejecta composition. Investigation of the nature of the internal energy dissipation mechanisms will be obtained through the systematic study with XGIS of the sub-second variability unexplored so far over such a wide energy range. THESEUS will follow the spectral evolution of the prompt emission down to the soft X–ray band during the early steep decay and through the plateau phase with the unique ability of extending above 10 keV the spectral study of these early afterglow emission phases.