ItemArticle

X-Ray Spectral Variability of the TeV High-energy Peaked Blazar PG 1553+113 with XMM-Newton

Title
X-Ray Spectral Variability of the TeV High-energy Peaked Blazar PG 1553+113 with XMM-Newton
Creator
Devanand, P.U.; Gupta, Alok C.; Wiita, Paul J.; Jithesh, V.; Gupta, Archana
Description
We present an extensive X-ray spectral variability study of the TeV photon-emitting high-energy-peaked BL Lacertae object PG 1553+113, using the data from the EPIC-PN camera of XMM-Newton, which observed the source during its operational period from 2001 September to 2024 November. X-ray spectra in the energy range, 0.67.0 keV, were fitted with absorbed power-law (PL) and absorbed log-parabola (LP) models. We found with 99% confidence that 14 of them were fit well by LP models having parameters in the range ??2.132.80, and ??0.040.18, one spectrum flavors an LP model with ?<0, while simple PL models with ??2.532.69 were sufficient to describe the X-ray spectra of the remaining 15. Of these 30 observations, 2 showed strong signatures of an additional inverse Compton component, while 1 showed weaker indications. On fitting joint Optical Monitor and EPIC-PN data with LP models, we found synchrotron peaks in the energy range of ?s?4.5948.61 eV. This indicates that the spectral evolution is probably caused by variations in particle acceleration or cooling conditions within the jet. 2026. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the https://creativecommons.org/licenses/by/4.0/. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Source
Astrophysical Journal;Volume;1002;Issue;2;Article No.;157;
Date
01-01-2026
Publisher
American Astronomical Society
Subject
BL Lacertae objects (158); Blazars (164); X-ray active galactic nuclei (2035)
Coverage
Devanand P.U., Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital, 263001, India, Department of Applied Physics/Physics, Mahatma Jyotiba Phule Rohilkhand University, Bareilly, 243006, India; Gupta A.C., Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital, 263001, India; Wiita P.J., Department of Physics, The College of New Jersey, 2000 Pennington Rd, Ewing, 08628-0718, NJ, United States; Jithesh V., Department of Physics and Electronics, Christ University, Hosur Main Rd, Bengaluru, 560029, India; Gupta A., Department of Applied Physics/Physics, Mahatma Jyotiba Phule Rohilkhand University, Bareilly, 243006, India
Rights
All Open Access; Gold Open Access; Green Open Access
Relation
ISSN: 0004637X;
Format
online
Language
English
Type
Article

Citation

Devanand, P.U.; Gupta, Alok C.; Wiita, Paul J.; Jithesh, V.; Gupta, Archana, “X-Ray Spectral Variability of the TeV High-energy Peaked Blazar PG 1553+113 with XMM-Newton,” CHRIST (Deemed To Be University) Institutional Repository, accessed June 21, 2026, https://archives.christuniversity.in/items/show/23592.

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