J 2025

Probing X-Ray Timing and Spectral Variability in the Blazar PKS 2155-304 over a Decade of XMM-Newton Observations

BHATTA, Gopal; Suvas Chandra CHAUDHARY; Niraj DHITAL; Tek P. ADHIKARI; Maksym MOHORIAN et al.

Základní údaje

Originální název

Probing X-Ray Timing and Spectral Variability in the Blazar PKS 2155-304 over a Decade of XMM-Newton Observations

Autoři

BHATTA, Gopal; Suvas Chandra CHAUDHARY; Niraj DHITAL; Tek P. ADHIKARI; Maksym MOHORIAN; Adithiya DINESH; Radim PÁNIS; Raghav NEUPANE a Yogesh Singh MAHARJAN

Vydání

Astrophysical Journal, GB - Spojené království Velké Británie a, 2025, 0004-637X

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Odkazy

URL

Impakt faktor

Impact factor: 5.400 v roce 2024

Organizační jednotka

Fyzikální ústav v Opavě

DOI

https://doi.org/10.3847/1538-4357/adb0c9

UT WoS

001436916100001

EID Scopus

2-s2.0-105000124548

Klíčová slova anglicky

Term optical variability;active galactic nuclei;log parabolic spectra;BL lacertae objects;MRK 421;particle acceleration;intraday variability;TeV blazars;synchronton emission;flux distibution

Štítky

RIV26, SGS-30-2023, UF

Příznaky

Mezinárodní význam, Recenzováno

Návaznosti

GA23-07043S, projekt VaV.
Změněno: 28. 1. 2026 12:22, Mgr. Pavlína Jalůvková

Anotace

V originále

Blazars, a class of active galactic nuclei (AGN) powered by supermassive black holes, are known for their remarkable variability across multiple timescales and wavelengths. Despite significant advancements in our understanding of AGN central engines, thanks to both ground- and space-based telescopes, the details of the mechanisms driving this variability remain elusive. The primary objective of this study is to constrain the X-ray variability properties of the TeV blazar PKS 2155-304. We conducted a comprehensive X-ray spectral and timing analysis, focusing on both long-term and intraday variability (IDV), using data from 22 epochs of XMM-Newton observations collected over 15 yr (2000-2014). For the timing analysis, we estimated the fractional variability, variability amplitude, minimum variability timescales, flux distribution, and power spectral density. In the spectral analysis, we fitted the X-ray spectra using power-law, log-parabola, and broken power-law models to determine the best-fitting parameters. We observed moderate IDV in the majority of the light curves (LCs). Seven out of the 22 observations showed a clear bimodal flux distribution, indicating the presence of two distinct flux states. Our analysis revealed a variable power spectral slope. Most hardness ratio plots did not show significant variation with flux, except for two observations, where the hardness ratio changed considerably with flux. The fitted X-ray spectra favored the broken power-law model for the majority of observations, indicating a break in the spectral profiles. The findings of this work shed light on the IDV of blazars, providing insights into the nonthermal jet processes that drive the observed flux variations.
Zobrazeno: 30. 1. 2026 06:57