The origin of the soft excess in the luminous quasar HE 1029-1401

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Vaia, B., Ursini, F., Matt, G., Ballantyne, D. R., Bianchi, S., De Rosa, A., Middei, R., Petrucci, P. O., Piconcelli, E., Tortosa, A.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917753331384320
author Vaia, B.
Ursini, F.
Matt, G.
Ballantyne, D. R.
Bianchi, S.
De Rosa, A.
Middei, R.
Petrucci, P. O.
Piconcelli, E.
Tortosa, A.
author_facet Vaia, B.
Ursini, F.
Matt, G.
Ballantyne, D. R.
Bianchi, S.
De Rosa, A.
Middei, R.
Petrucci, P. O.
Piconcelli, E.
Tortosa, A.
contents The enigmatic and intriguing phenomenon of the "soft excess" observed in the X-ray spectra of luminous quasars continues to be a subject of considerable interest and debate in the field of high-energy astrophysics. This study focuses on the quasar HE 1029-1401 ($z=0.086$, $\log(L_{\rm{bol}}/[\rm{erg\,s^{-1}}])= 46.0 \pm 0.2$), with a particular emphasis on investigating the properties of the hot corona and the physical origin of the soft excess. In this study, we present the results of a joint \textit{XMM-Newton}/\textit{NuSTAR} monitoring campaign of this quasar conducted in May 2022. The source exhibits a cold and narrow Fe $\rm{K}α$ emission line at 6.4 keV, in addition to the detection of a broad component. Our findings suggest that the soft excess observed in HE 1029-1401 can be adequately explained by Comptonized emission originating from a warm corona. Specifically, fitting the spectra with two \nthcomp\, component we found that the warm corona is characterized by a photon index ($Γ^{w}$) of $2.75\pm0.05$ and by an electron temperature ($kT_{e}^{w}$) of $0.39^{+0.06}_{-0.04}$ keV, while the optical depth ($τ^{w}$) is found to be $23\pm3$. We also test more physical models for the warm corona, corresponding to two scenarios: pure Comptonization and Comptonization plus reflection. Both models provide a good fit to the data, and are in agreement with a radially extended warm corona having a size of a few tens of gravitational radii.
format Preprint
id arxiv_https___arxiv_org_abs_2405_13479
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle The origin of the soft excess in the luminous quasar HE 1029-1401
Vaia, B.
Ursini, F.
Matt, G.
Ballantyne, D. R.
Bianchi, S.
De Rosa, A.
Middei, R.
Petrucci, P. O.
Piconcelli, E.
Tortosa, A.
High Energy Astrophysical Phenomena
The enigmatic and intriguing phenomenon of the "soft excess" observed in the X-ray spectra of luminous quasars continues to be a subject of considerable interest and debate in the field of high-energy astrophysics. This study focuses on the quasar HE 1029-1401 ($z=0.086$, $\log(L_{\rm{bol}}/[\rm{erg\,s^{-1}}])= 46.0 \pm 0.2$), with a particular emphasis on investigating the properties of the hot corona and the physical origin of the soft excess. In this study, we present the results of a joint \textit{XMM-Newton}/\textit{NuSTAR} monitoring campaign of this quasar conducted in May 2022. The source exhibits a cold and narrow Fe $\rm{K}α$ emission line at 6.4 keV, in addition to the detection of a broad component. Our findings suggest that the soft excess observed in HE 1029-1401 can be adequately explained by Comptonized emission originating from a warm corona. Specifically, fitting the spectra with two \nthcomp\, component we found that the warm corona is characterized by a photon index ($Γ^{w}$) of $2.75\pm0.05$ and by an electron temperature ($kT_{e}^{w}$) of $0.39^{+0.06}_{-0.04}$ keV, while the optical depth ($τ^{w}$) is found to be $23\pm3$. We also test more physical models for the warm corona, corresponding to two scenarios: pure Comptonization and Comptonization plus reflection. Both models provide a good fit to the data, and are in agreement with a radially extended warm corona having a size of a few tens of gravitational radii.
title The origin of the soft excess in the luminous quasar HE 1029-1401
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2405.13479