Spectral analysis of the AMXP during its 2018 outburst

The Accreting Millisecond X-ray Pulsar IGR J17591-2342 is a Low Mass X-ray Binary (LMXB) system that went in outburst on 2018 August and it was monitored by the NICER observatory and partially by other facilities. We aim to study how the spectral emission of this source evolved during the outburst by exploiting the whole X-ray data repository of simultaneous observations. The continuum emission of the combined broad-band spectra is on average well described by an absorbed Comptonization component scattering blackbody-distributed photons peaking at (0.8 +/- 0.5) keV by a moderately optically thick corona (tau = 2.3 +/- 0.5) with temperature of (34 +/- 9) keV. A blackbody component with tempe…