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J/MNRAS/458/56 TeV gamma-ray blazar X-ray spectral studies (Wierzcholska+, 2016)

X-ray spectral studies of TeV gamma-ray emitting blazars. Wierzcholska A., Wagner S.J. <Mon. Not. R. Astron. Soc., 458, 56-83 (2016)> =2016MNRAS.458...56W (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Gamma rays ; X-ray sources ; Redshifts Keywords: radiation mechanisms: non-thermal - galaxies: active - BL Lacertae objects: general - galaxies: jets Abstract: This work is a summary of the X-ray spectral studies of 29TeV (1012eV, tera-electron-volt) γ-ray emitting blazars observed with Swift/XRT, especially focusing on sources for which the X-ray regime allows us to study the low- and the high-energy ends of the particle distribution function. Variability studies require simultaneous coverage, ideally sampling different flux states of each source. This is achieved using X-ray observations by disentangling the high-energy end of the synchrotron emission and the low-energy end of the Compton emission, which are produced by the same electron population. We focused on a sample of 29 TeV γ-ray emitting blazars with the best signal-to-noise X-ray observations collected with Swift/XRT in the energy range 0.3-10keV during 10yr of Swift/XRT operations. We investigate the X-ray spectral shapes and the effects of different corrections for neutral hydrogen absorption and decompose the synchrotron and inverse Compton components. For five sources (3C 66A, S5 0716+714, W Comae, 4C +21.35 and BL Lacertae) a superposition of both components is observed in the X-ray band, permitting simultaneous, time-resolved studies of both ends of the electron distribution. The analysis of multi-epoch observations revealed that the break energy of the X-ray spectrum varies only by a small factor with flux changes. Flux variability is more pronounced in the synchrotron domain (high-energy end of the electron distribution) than in the Compton domain (low-energy end of the electron distribution). The spectral shape of the Compton domain is stable, while the flux of the synchrotron domain is variable. These changes cannot be described by simple variations of the cut-off energy, suggesting that the high-energy end of the electron distribution is not generally well described by cooling only. Description: The catalogue of TeV sources (TeVCat, http://tevcat.uchicago.edu) includes 161 objects and 58 of them are classified as blazars. All of the blazars have been observed several times with Swift/XRT. The main properties of the TeV blazars, as well as the total exposure in the PC mode and integrated flux for the energy range 0.3-10keV obtained using the online analysis of Swift/XRT data (Evans et al., 2009, Cat. J/MNRAS/397/1177), are collected in Table 1. For the 29 selected blazars, the Swift/XRT data were analysed using HEASoft package v. 6.16 software with CALDB v. 20140120. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 145 59 Summary of tera-electron-volt blazars refs.dat 157 91 References table2.dat 79 58 Comparison of Galactic column density values table3.dat 63 116 Fit parameters for the log-parabola fits for 29 sources table4.dat 67 116 Fit parameters for power-law fits for 29 sources table5.dat 76 20 Fit parameters for broken power-law fits for 5 sources
See also: J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 21 A21 --- Name Object name 23- 24 A2 --- r_Name TeV detection reference, in refs.dat file 26- 27 I2 h RAh Right ascension (J2000) 29- 30 I2 min RAm Right ascension (J2000) 32- 35 F4.1 s RAs Right ascension (J2000) 37 A1 --- DE- Declination sign (J2000) 38- 39 I2 deg DEd Declination (J2000) 41- 42 I2 arcmin DEm Declination (J2000) 44- 45 I2 arcsec DEs Declination (J2000) 47- 50 A4 --- Type Type of blazar 52 A1 --- l_z Limit flag on z 53- 58 F6.4 --- z ?=9.999 Redshift 59- 60 A2 --- r_z Redshift reference, in refs.dat file 62- 67 F6.2 10-15W/m2 FPC ? Integrated flux for Swift/XRT observations in PC mode in the energy range 0.3-10keV 69- 73 F5.1 ks ExpPC ? Exposure for Swift/XRT observations in PC mode in the energy range 0.3-10keV 75- 79 F5.2 10-18W/cm2 FPCxExpPC ? Product FPC and ExpPC (in 10-11erg/cm2) 81 A1 --- Flag [+] + for blazars selected for further detailed studies 83-145 A63 --- Note Note
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 2 A2 --- Ref Reference code 4- 22 A19 --- BibCode BibCode 24- 60 A37 --- Aut Author's name 62-157 A96 --- Com Comments
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 21 A21 --- Name Object Name 24- 28 F5.2 10+20cm-2 NHLAB NH value provided by Kalberla et al. (2005A&A...440..775K, Cat. VIII/76) 30- 34 F5.2 10+20cm-2 NHDL NH value provided by Dickey & Lockman (1990ARA&A..28..215D) 36- 40 F5.2 10+20cm-2 NHH2 NH2 value provided by Willingale et al. (2013MNRAS.431..394W) 42- 46 F5.2 10+20cm-2 NHWill NH value provided by Willingale13 48- 52 F5.2 10+20cm-2 NHLPFree ?=- Free NH value obtained with log-parabola model fitted 54- 57 F4.2 10+20cm-2 e_NHLPFree ?=- rms uncertainty on NHLPFree 59- 63 F5.2 10+20cm-2 NHPLFree ?=- Free NH value obtained with power-law model fitted 65- 68 F4.2 10+20cm-2 e_NHPLFree ?=- rms uncertainty on NHPLFree 70- 74 F5.2 10+20cm-2 NHBPFree ?=- Free NH value obtained with broken power-law model fitted 76- 79 F4.2 10+20cm-2 e_NHBPFree ?=- rms uncertainty on NHBPFree
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Object name 17- 20 A4 --- Ref Source of NH value (G1) 22- 25 F4.2 --- alpha α parameter 27- 30 F4.2 --- e_alpha rms uncertainty on alpha 32- 36 F5.2 --- beta β parameter 38- 41 F4.2 --- e_beta rms uncertainty on beta 43- 47 F5.3 10-2/cm2/s/keV Nl Normalization for the log-parabola fit defined in Section 3 49- 53 F5.3 10-2/cm2/s/keV e_Nl rms uncertainty on Nl 55- 59 F5.3 --- rchi2 Reduced χ2 value 60 A1 --- --- [/] 61- 63 I3 --- DOF Number of degrees of freedom
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Object name 17- 20 A4 --- Ref Source of NH value (G1) 22- 25 F4.2 --- GAMMA Spectral index 27- 30 F4.2 --- e_GAMMA rms uncertainty on GAMMA 32- 36 F5.3 10-2/cm2/c/keV Np Normalization for the power-law fit defined in Sect.3 38- 42 F5.3 10-2/cm2/c/keV e_Np rms uncertainty on Np 44- 48 F5.3 --- rchi2 Reduced χ2 value 50- 52 I3 --- DOF Number of degrees of freedom 54- 58 F5.1 --- F Test statistics value for F-test 60- 64 E5.2 --- pvalue Probability 66- 67 A2 --- Model Preferable model (1)
Note (1): Preferable model as follows: PO = power-law LP = log-parabola model
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Name Object name 15- 18 A4 --- Ref Source of NH value (G1) 20- 24 F5.3 --- GAMMA1 First spectral index 26- 30 F5.3 --- e_GAMMA1 rms uncertainty on GAMMA1 32- 36 F5.3 --- GAMMA2 Second spectral index 38- 42 F5.3 --- e_GAMMA2 rms uncertainty on GAMMA2 44- 48 F5.3 10-2/cm2/s/keV Nb Normalization for the power-law fit defined in Sect.3 50- 54 F5.3 10-2/cm2/s/keV e_Nb rms uncertainty on Nb 56- 60 F5.3 keV Eb Break energy for the broken power-law fit defined in Sect. 3 62- 66 F5.3 keV e_Eb rms uncertainty on Eb 68- 72 F5.3 --- rchi2 Reduced χ2 value 74- 76 I3 --- DOF Number of degrees of freedom
Global notes: Note (G1): Source of NH value as follows: LAB = Kalberla et al. (2005A&A...440..775K, Cat. VIII/76) DL = Dickey & Lockman (1990ARA&A..28..215D) Will = Willingale et al. (2013MNRAS.431..394W) Free = free NH value
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 25-Nov-2016
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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