Abstract Details
| Name: Devanand P U |
| Affiliation: Aryabhatta Research Institute of Observational Sciences |
| Conference ID: ASI2026_333 |
| Title: X-ray spectral variability studies of TeV HBL PG 1553+113 using XMM-Newton |
| Abstract Type: Poster |
| Abstract Category: High Energy Phenomena, Fundamental Physics and Astronomy |
| Author(s) and Co-Author(s) with Affiliation: P. U. Devanand(Aryabhatta Research Institute of Observational Sciences (ARIES, Nainital-263001, India), Alok C. Gupta(Aryabhatta Research Institute of Observational Sciences (ARIES, Nainital-263001, India), Paul J. Witta(Department of Physics, The College of New Jersey, 2000 Pennington Rd., Ewing, NJ 08628-0718, USA), V. Jithesh(Department of Physics and Electronics, Christ University, Hosur Main Road, Bengaluru 560029, India), Archana Gupta(Department of Applied Physics/Physics, Mahatma Jyotiba Phule Rohilkhand University, Bareilly 243006, India) |
| Abstract: We present a detailed study of TeV HBL PG 1553+113's X-ray spectral variability using data from XMM-Newton's EPIC PN camera in the energy range of 0.6-7.0 keV, covering the observation period from September 2001 to November 2024. We found 14 of the X-ray spectra to be fitted with absorbed log-parabolic (LP) models with local photon index α ≃ 2.13 − 2.80, and curvature parameter β ≃ 0.04 − 0.18. The PL model was sufficient to describe X-ray spectra of 15 of them with photon index in the range Γ ≃ 2.53 − 2.69. Two observations suggest a strong possibility of the existence of an additional IC component in their X-ray spectra. We fitted joint X-ray+Optical spectra with log parabola models to estimate synchrotron peaks in the energy range νs ≃ 4.59 − 48.61 eV. This suggests that spectral variation is likely produced by variations in particle accelerations and subsequent cooling within the jet. |