J/MNRAS/439/690 Optical/γ-ray variability in blazars (Hovatta+, 2014)
Connection between optical and γ-ray variability in blazars.
Hovatta T., Pavlidou V., King O.G., Mahabal A., Sesar B., Dancikova R.,
Djorgovski S.G., Drake A., Laher R., Levitan D., Max-Moerbeck W.,
Ofek E.O., Pearson T.J., Prince T.A., Readhead A.C.S., Richards J.L.,
Surace J.
<Mon. Not. R. Astron. Soc., 439, 690-702 (2014)>
=2014MNRAS.439..690H 2014MNRAS.439..690H
ADC_Keywords: BL Lac objects ; QSOs ; Gamma rays
Keywords: galaxies: active; BL Lacertae objects: general; galaxies: jets
quasars: general
Abstract:
We use optical data from the Palomar Transient Factory (PTF) and the
Catalina Real-Time Transient Survey (CRTS) to study the variability of
γ-ray-detected and non-detected objects in a large population of
active galactic nuclei selected from the Candidate Gamma-Ray Blazar
Survey and Fermi Gamma-Ray Space Telescope catalogues. Our
samples include 714 sources with PTF data and 1244 sources with CRTS
data. We calculate the intrinsic modulation index to quantify the
optical variability amplitude in these samples.
Description:
We use the AGN sample defined by Richards et al. (2011ApJS..194...29R 2011ApJS..194...29R,
Cat. J/ApJS/194/29) and monitored by them at 15GHz at the Owens
Valley Radio Observatory (OVRO) 40-m as the starting point for our
analysis. This sample of 1771 objects includes 1158 sources from the
Candidate Gamma-ray Blazar Survey (CGRaBS; Healey et al.,
2008ApJS..175...97H 2008ApJS..175...97H, Cat. J/ApJS/175/97) and all the sources above
declination -20° that have been detected by the LAT in the first
and second AGN catalogues (Abdo et al., 2010ApJ...715..429A 2010ApJ...715..429A, Cat.
J/ApJ/715/429; Ackermann et al., 2011ApJ...743..171A 2011ApJ...743..171A, Cat.
J/ApJ/743/171). The OVRO sample also includes a small number of
objects with interesting jet properties or that are being monitored by
other programs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 121 714 Sources in PTF sample (Palomar Transient Factory)
table3.dat 121 1244 Sources in CRTS sample (Catalina Real-Time
Transient Survey)
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See also:
J/ApJS/175/97 : CGRaBS: survey of gamma-ray blazar candidates (Healey+ 2008)
J/ApJ/715/429 : First Fermi-LAT AGN catalog (1LAC) (Abdo+, 2010)
J/ApJ/743/171 : The 2LAC catalog (Ackermann+, 2011)
J/ApJS/194/29 : Observations of blazars at 15GHz (Richards+, 2011)
J/MNRAS/438/3058 : 15GHz variability of gamma-ray blazars (Richards+, 2014)
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name OVRO (Owens Valley Radio Observatory) name
26- 27 I2 h RAh Right ascension (J2000)
29- 30 I2 min RAm Right ascension (J2000)
32- 36 F5.2 s RAs Right ascension (J2000)
38 A1 --- DE- Declination sign (J2000)
39- 40 I2 deg DEd Declination (J2000)
42- 43 I2 arcmin DEm Declination (J2000)
45- 49 F5.2 arcsec DEs Declination (J2000)
51- 66 A16 --- Fermi Fermi association
(1FGLJHHMM.m+DDMM or 2FGLJHHMM.m+DDMM)
68- 75 F8.6 --- z [0/3.9]?=- Redshift
77 I1 --- r_z ? Redshift reference (1)
79 A1 --- Cl Optical class (2)
81- 83 A3 --- SED SED class (3)
85- 89 F5.3 --- m [0/7]?=- Intrinsic modulation index (4)
91- 95 F5.3 --- e_m ?=- Error on m (lower value)
97-101 F5.3 --- E_m ?=- Error on m (upper value)
103-109 F7.3 Jy S0 ?=- Intrinsic mean optical flux density S0
111-115 F5.3 Jy e_S0 ?=- Error on S0 (lower value)
117-121 F5.3 Jy E_S0 ?=- Error on S0 (upper value)
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Note (1): Redshift references as follows:
1 = Healey et al. (2008ApJS..175...97H 2008ApJS..175...97H, Cat. J/ApJS/175/97)
2 = Abdo et al. (2010Natur.463..919A 2010Natur.463..919A)
3 = Ackermann et al. (2011ApJ...743..171A 2011ApJ...743..171A, Cat. J/ApJ/743/171)
4 = Landoni et al. (2012A&A...543A.116L 2012A&A...543A.116L)
Note (2): Optical class code as follows:
Q = FSRQ, flag spectrum radio quasar
B = BL Lac object
G = galaxy
A = active galactic nucleus
N = narrow-line Seyfert 1 galaxy
U = unidentified
Note (3): SED class from Ackermann et al. (2011, Cat. J/ApJ/715/429) as follows:
HSP = high-synchrotron-peaked blazar
ISP = intermediate-synchrotron-peaked blazar
LSP = low-synchrotron-peaked blazar
Note (4): Intrinsic modulation index m defined as m=σ0/S0 where
σ0 is the intrinsic standard deviation and S0 the intrinsic
mean flux density.
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History:
* 15-Dec-2014: From electronic version of the journal
* 06-May-2016: Some sign of declinations corrected in both tables
(End) Patricia Vannier [CDS] 15-Dec-2014