X-Ray Spectral Variability of Thirteen TeV High Energy Peaked Blazars with XMM-Newton

Abstract

We present a comprehensive study of the X-ray spectral variability observed in 13 TeV photon emitting high energy peaked BL Lacs(HBLs). These data come from 54 XMM-Newton EPIC-PN pointed observations made during its operational period from June 2001 through July 2023. We performed spectral studies in the energy range 0.6-10 keV by fitting X-ray spectra of the pointed observations with power law (PL) and log parabolic (LP) models. We found at 99% confidence level that 31 of these X-ray spectra were best fitted with a range of LP models with local photon indices (at 1.0 keV), alpha in the range of 1.75-2.66, and convex curvature parameter beta in the range of 0.02-0.25. PL models with photon index Gamma in the range of 1.78-2.68 best described the spectra of fourteen-pointed observations. Nine PN spectra resulted in negative curvature parameters in fitting an LP model, and eight among them were significant (beta is at least twice beta_err). We fitted broken power law (BPL) models to these eight X-ray spectra and found spectral hardening (Delta_Gamma) in the range of 0.06-0.54 for these observations. EPIC-MOS spectra were also studied for those eight observations to search for similar trends, and we were able to find them in only two, one observation each of PKS 0548-322 and Mrk 501. This indicates the possibility of the co-existence of an inverse Compton component along with the dominant synchrotron component for these two observations. We also performed correlation studies between various log-parabolic spectral parameters and briefly discuss their possible implications.

51 pages, 7 tables, 6 figures Accepted for publication in ApJ/ApJS

References in corpus (35)

• HI4PI: A full-sky HI survey based on EBHIS and GASS
• MAGIC discovery of VHE Emission from the FSRQ PKS 1222+21
• New constraints on the Mid-IR EBL from the HESS discovery of VHE gamma rays from 1ES 0229+200
• Multiwavelength Observations of Markarian 421 in March 2001: an Unprecedented View on the X-ray/TeV Correlated Variability
• The Spectral Energy Distributions of Fermi Blazars
• The XMM-Newton EPIC Background and the production of Background Blank Sky Event Files
• X-ray spectral evolution of TeV BL Lac objects: eleven years of observations with BeppoSAX, XMM-Newton and SWIFT satellites
• Signatures of synchrotron emission and of electron acceleration in the X-ray spectra of Mrk 421
• Discovery of VHE gamma-rays from the distant BL Lac 1ES 0347-121
• Simultaneous multiwavelength observations of the blazar 1ES1959+650 at a low TeV flux
• On the redshift of TeV BL Lac objects
• Multiwavelength observations of Mrk 501 in 2008
• New hard-TeV extreme blazars detected with the MAGIC telescopes
• Long-term Monitoring on Mrk 501 for Its VHE gamma Emission and a Flare in October 2011
• X-ray spectra, light-curves and SEDs of blazars frequently observed by Swift
• Study of the variable broadband emission of Markarian 501 during the most extreme Swift X-ray activity
• Investigating Broadband Variability of the TeV Blazar 1ES 1959+650
• XMM-Newton observations of the TeV BL Lac object PKS 2155--304 in 2006: signature of inverse Compton X-ray emission?
• Detection of X-ray Polarization from the Blazar 1ES 1959+650 with the Imaging X-ray Polarimetry Explorer
• Very High Energy outburst of Markarian 501 in May 2009
• Swift observations of Mrk\,421 in selected epochs. iii. Extreme x-ray timing/spectral properties and multiwavelength lognormality in 2015\,December--2018\,April
• An intermittent extreme BL Lac: MWL study of 1ES 2344+514 in an enhanced state
• Multiwavelength Observations of 1ES 1959+650, One Year After the Strong Outburst of 2002
• The Hard X-ray emission of the blazar PKS 2155--304
• Swift XRT and UVOT deep observations of the high energy peaked BL Lac object PKS 0548-322 close to its brightest state
• X-ray Intraday Variability of HBL Blazars with XMM-Newton
• X-ray timing and spectral variability properties of blazars S5 0716+714, OJ 287, Mrk 501, and RBS 2070
• Broadband Study of High-Synchrotron-Peaked BL Lac Object 1ES 1218+304
• Probing the Transition Between the Synchrotron and Inverse-compton Spectral Components of 1ES 1959+650
• X-ray spectral variations of synchrotron peak in BL Lacs
• Multi-year characterisation of the broad-band emission from the intermittent extreme BL Lac 1ES~2344+514
• Search for TeV $\gamma$--ray emission from blazar 1ES1218+304 with TACTIC telescope during March-April 2013
• X-ray Studies of Blazar 1ES 1959+650 Using SWIFT & XMM-NEWTON Satellite
• Constraining X-ray emission in HBL blazars using multiwavelength observations
• NuSTAR View of TeV Blazar Mrk 501

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