A dataset provided by the European Space Agency

Proposal ID 0520037
Obs ID 05200370001
Title Spectral variability of NGC 4151
Download Data Associated to the proposal https://isla.esac.esa.int/tap/download/bundle?format=ascii_curl&product_id=prop_id:0520037
DOI https://doi.org/10.57780/esa-bn1qckm
Author Walter
Abstract We propose to monitor NGC 4151 with INTEGRAL to accurately and simultaneously measure the spectral shape up to above 200 keV and to study large amplitude variations with an unprecedented sensitivity and time coverage at high energy. We will correlate the high energy spectral cutoff with other continuum parameters to confirm thermal comptonisation and determine the main physical mechanism driving the variability. We will also disentangle the reflection hump and its variations from the primary continuum and intrinsic absorption and correlate those with the narrow iron line variability to determine the nature of the thick reprocessing medium and the geometry of cold matter surrounding the source. We will finally probe for the existence of a hard non thermal tail which will constrain the electrons acceleration mechanisms. We request 4 observations of 400 ksec each.
Publications
Temporal Coverage 2007-12-22T17:53:27Z / 2007-12-31T01:54:24Z
Version 1.0
Mission Description The INTEGRAL (International Gamma-Ray Astrophysics Laboratory) mission, launched by the European Space Agency (ESA) on October 17, 2002, was designed to study high-energy phenomena in the universe. INTEGRAL was operating until february 2025 and it was equipped with three high-energy instruments: the Imager on Board the INTEGRAL Satellite (IBIS), the Spectrometer on INTEGRAL (SPI), and the JEM-X (Joint European Monitor for X-rays). Its Optical Monitoring Camera (OMC) provided optical V-band magnitude measurements, complementing the high-energy observations.
Creator Contact https://www.cosmos.esa.int/web/integral/helpdesk
Date Published 2025-03-25T09:54:34Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, Walter, 2025, 'Spectral variability of NGC 4151', 1.0, European Space Agency, https://doi.org/10.57780/esa-bn1qckm