X-ray spectra, light-curves and SEDs of blazars frequently observed by Swift

Abstract

Blazars research is one of the hot topics of contemporary extra-galactic astrophysics. That is because these sources are the most abundant type of extra-galactic gamma-ray sources and are suspected to play a central role in multi-messenger astrophysics. We have used swift_xrtproc, a tool to carry out an accurate spectral and photometric analysis of the Swift-XRT data of all blazars observed by Swift at least 50 times between December 2004 and the end of 2020. We present a database of X-ray spectra, best-fit parameter values, count-rates and flux estimations in several energy bands of over 31,000 X-ray observations and single snapshots of 65 blazars. The results of the X-ray analysis have been combined with other multi-frequency archival data to assemble the broad-band Spectral Energy Distributions (SEDs) and the long-term light-curves of all sources in the sample. Our study shows that large X-ray luminosity variability on different timescales is present in all objects. Spectral changes are also frequently observed with a "harder-when-brighter" or "softer-when-brighter" behavior depending on the SED type of the blazars. The peak energy of the synchrotron component nu_peak in the SED of HBL blazars, estimated from the log-parabolic shape of their X-ray spectra, also exhibits very large changes in the same source, spanning a range of over two orders of magnitude in Mrk421 and Mrk501, the objects with the best data sets in our sample.

arXiv commentAccepted for publication in MNRAS

References in corpus (31)

• Unified Schemes for Radio-Loud Active Galactic Nuclei
• The Swift X-ray Telescope
• Fermi Large Area Telescope Fourth Source Catalog
• Neutrino emission from the direction of the blazar TXS 0506+056 prior to the IceCube-170922A alert
• The Spectral Energy Distribution of Fermi bright blazars
• Active Galactic Nuclei: what's in a name?
• The Connection between X-ray- and Radio-Selected BL Lacertae Objects
• The 5th edition of the Roma-BZCAT. A short presentation
• BeppoSAX Observations of Unprecedented Synchrotron Activity in the BL Lac Object Mkn 501
• SMARTS optical and infrared monitoring of 12 gamma-ray bright blazars
• Science with the Cherenkov Telescope Array
• Log-parabolic spectra and particle acceleration in blazars. III: SSC emission in the TeV band from Mkn 501
• Simultaneous Planck, Swift, and Fermi observations of X-ray and gamma-ray selected blazars
• Dissecting the region around IceCube-170922A: the blazar TXS 0506+056 as the first cosmic neutrino source
• Swift observations of the X-ray bright GRB 050315
• Chi-square and Poissonian Data: Biases Even in the High-Count Regime and How to Avoid them
• The 3HSP catalogue of Extreme & High Synchrotron Peaked Blazars
• Fermi Large Area Telescope Fourth Source Catalog Data Release 2
• Dissecting the regions around IceCube high-energy neutrinos: growing evidence for the blazar connection
• Progress in unveiling extreme particle acceleration in persistent astrophysical jets
• Connecting blazars with ultra high energy cosmic rays and astrophysical neutrinos
• Detection of Exceptional X-Ray Spectral Variability in the TeV BL Lac 1ES 2344+514
• The Open Universe VOU-Blazars tool
• Open Universe for Blazars: a new generation of astronomical products based on 14 years of Swift-XRT data
• Swift observations of Mrk\,421 in selected epochs. iii. Extreme x-ray timing/spectral properties and multiwavelength lognormality in 2015\,December--2018\,April
• AGILE and Swift simultaneous observations of the blazar S50716+714 during the bright flare of October 2007
• Multicolor Optical Monitoring of the Blazar S5 0716+714 from 2017 to 2019
• Systematic investigation of X-ray spectral variability of TeV blazars during flares in the $RXTE$ era
• The strange case of the transient HBL blazar 4FGL J1544.3-0649
• Detection of VHE gamma-ray transients with monitoring facilities
• The Open Universe survey of Swift-XRT GRB fields: a complete sample of HBL blazars

Cited by in corpus (23)

• A multi-messenger study of the blazar PKS 0735+178: a new major neutrino source candidate
• X-ray Polarization of BL Lacertae in Outburst
• X-ray Polarization Observations of BL Lacertae
• IXPE observation of PKS 2155-304 reveals the most highly polarized blazar
• A thirteen-year-long broadband view of BL Lac
• The first hard X-ray spectral catalogue of Blazars observed by NuSTAR
• Dissecting the broadband emission from γ-ray blazar PKS 0735+178 in search of neutrinos
• Modeling the time variable spectral energy distribution of the blazar CTA 102 from 2008 to 2022
• Can MAD accretion disks launching structured jets explain both GRB and AGN engines? Magnetically arrested accretion disks launching structured jets in application to GRB and AGN engines
• Long-term multi-wavelength study of 1ES 0647+250
• Correlated Short-Timescale Hard-Soft X-ray Variability of the Blazars Mrk 421 and 1ES 1959+650 using $\text{AstroSat}$
• A QPO in Mkn 421 from Archival RXTE Data
• Origin of multiwavelength emission from flaring high redshift blazar PKS 0537-286
• Unusual Hard X-ray Flares Caught in NICER Monitoring of the Binary Supermassive Black Hole Candidate AT2019cuk/Tick Tock/SDSS J1430+2303
• Hunting for neutrino emission from multi-frequency variable sources
• Multi-frequency Variability Study of Flat-Spectrum Radio Quasar PKS 0346-27
• Insights from leptohadronic modelling of the brightest blazar flare
• The Spectra of IceCube Neutrino (SIN) candidate sources -- IV. Spectral energy distributions and multi-wavelength variability
• X-Ray Spectral Variability of Thirteen TeV High Energy Peaked Blazars with XMM-Newton
• Central Engine and Spectral Energy Distribution Properties of High Redshift Gamma Ray Blazars
• The traveling-PWN modeling attempt on the enigmatic LHAASO dumbbell-like structure
• Detectability of Polarized Gamma-ray Emission from Blazar Flares with COSI
• On the origin of mid-infrared colors in $\gamma$-ray blazars