J/A+A/562/A79 Variability of seven blazars in six bands (Sandrinelli+, 2014)
Long and short term variability of seven blazars in six near-infrared/optical
bands.
Sandrinelli A., Covino S., Treves A.
<Astron. Astrophys. 562, A79 (2014)>
=2014A&A...562A..79S 2014A&A...562A..79S
ADC_Keywords: QSOs ; Photometry, VRI ; Photometry, infrared
Keywords: BL Lacertae objects: general - galaxies: photometry - galaxies: active
Abstract:
We present the light curves of six BL Lac objects, PKS 0537-441,
PKS 0735+17, OJ 287, PKS 2005-489, PKS 2155- 304, W Comae, and of the
Flat Spectrum Radio Quasar PKS 1510-089, as a part of a photometric
monitoring program in the near-infrared/optical bands started in 2004.
All sources are Fermi Blazars. Our purpose is to investigate flux and
spectral variability at short and long time scales. Systematic
monitoring, independent of the activity of the source, guarantees high
statistics, and allows to draw an unbiased view of different activity
states on weekly/daily time scales for the whole timeframe, and on
nightly timescales for some epochs. Data were obtained with the REM
telescope located at the ESO premises of La Silla (Chile). Light
curves were gathered in the optical/near-infrared VRIJHK bands from
2005 April to 2012 June. Variability ≳3mag is observed in
PKS 0537-441, PKS 1510-089 and PKS 2155-304, the largest ranges
spanned in the near-infrared. The color intensity plots show rather
different morphologies. The spectral energy distributions in general
are well fitted by a power law, with some deviations which are more
apparent in low states. Some variability episodes during a night
interval are well documented for PKS 0537-441 and PKS 2155-304. For
the latter source the variability time scale implies a large
relativistic beaming factor.
Description:
The Rapid Eye Mounting Telescope (REM) is a robotic telescope located
at the ESO Cerro La Silla observatory (Chile). In this paper we
consider optical (from ROSS camera; Jonson-Cousins VRI filters) and
NIR (from REMIR camera) data in VRIJHK bands (from 0.55 to 2.15um),
collected from 2005 April 11 (53471 MJD) to 2012 June 30 (56108 MJD).
Instrumental magnitudes were obtained via aperture photometry, using
aperture radii of 5" and typically with 300s integration time in the
optical and 150s integration time in the NIR.
The table contains the photometry nightly averaged data related
to light curves in Fig. 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 7 Blazars sample
photom.dat 32 10220 Photometry related to the light curves in Fig.2
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See also:
J/ApJ/722/520 : Gamma-ray light curves of Fermi blazars (Abdo+, 2010)
J/A+AS/129/569 : BVRI photometry of OJ 287 (Jia Guibin+ 1998)
J/AJ/132/1256 : eim BATC photometry of OJ 287 (Wu+, 2006)
J/MNRAS/385/823 : UBVRI light curves of OJ 287 (Zheng+, 2008)
J/MNRAS/402/2087 : Optical polarization of OJ 287 (Villforth+, 2010)
J/AJ/141/65 : BATC ceimo light curves of OJ 287 (Dai+, 2011)
J/MNRAS/421/1861 : OJ287 polarization and VLBI jet direction (Valtonen+, 2012)
J/ApJS/192/12 : Photometry of the blazar PKS 0537-441 (Impiombato+, 2011)
J/A+A/469/503 : VRIJHK observations of PKS 2155-304 (Dolcini+, 2007)
J/A+A/531/A123 : Optical light curve of PKS 2155-304 (Kastendieck+, 2011)
J/A+A/539/A149 : Multiwavelength view of PKS 2155-304 (Abramowski+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 23 F5.2 s RAs Right ascension (J2000)
25 A1 --- DE- Declination sign (J2000)
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 36 F5.2 arcsec DEs Declination (J2000)
38- 43 A6 --- Class Optical class from Massaro et al., 2012,
Multifrequency Catalogue of Blazars
(3rd Edition) (ARACNE Ed.)
45- 47 A3 --- SED SED class (1)
49- 54 F6.4 --- z Redshift from SIMBAD
56 A1 --- TeV? [Y:] TeV source (2)
58 A1 --- Ref [a-e] Reference (3)
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Note (1): Classification from Abdo et al. (2010, Cat. J/ApJ/722/520) on the
Spectral Energy Distribution as follows:
LSP = low synchrotron peaked (νS<1014Hz, where νS is the
synchrotron peak frequency)
ISP = intermediate synchrotron peaked (1014Hz<νS<1015Hz)
HSP = high synchrotron peaked (νS>1015Hz) blazars
Note (2): TeV sources from TeVCat: http://tevcat.unichicago.edu/
Note (3): References as follows:
a = Zhang et al. (2013MNRAS.428.3630Z 2013MNRAS.428.3630Z), D'Ammando et al. (2013MNRAS.431.2481D 2013MNRAS.431.2481D),
Impiombato et al. (2011, Cat. J/ApJS/192/12), D'Ammando et al. (2011,
Advances in Space Research, 48, 76), D'Ammando et al. (2010, 38th COSPAR
Scientific Assembly, 38, 2240), Pucella et al. (2010A&A...522A.109P 2010A&A...522A.109P),
Impiombato et al. (2008, Blazar Variability across the Electromagnetic
Spectrum, 43), Pian et al. (2007ApJ...664..106P 2007ApJ...664..106P),
Dolcini et al. (2005A&A...443L..33D 2005A&A...443L..33D)
b = D'Ammando et al. (2013b, in prep.)
c = D'Ammando et al. (2011, Advances in Space Research, 48, 76),
D'Ammando et al. (2011, Journal of Physics Conference Series, 280, 012002),
D'Ammando et al. (2011A&A...529A.145D 2011A&A...529A.145D), D'Ammando et al. (2010, 38th
COSPAR Scientific Assembly, 38, 2240), D'Ammando et al. (2010, Accretion
and Ejection in AGN: a Global View, 427, 271), D'Ammando et al. (2010,
X-ray Astronomy 2009; Present Status, Multi-Wavelength Approach and Future
Perspectives, 1248, 415)
d = Covino et al. (2010, 38th COSPAR Scientific Assembly, 38, 2282),
Impiombato et al. (2008, Blazar Variability across the Electromagnetic
Spectrum, 43), Foschini et al. (2008A&A...484L..35F 2008A&A...484L..35F), Dolcini et al.
(2007, Cat. J/A+A/469/503)
e = D'Ammando et al. (2011, Advances in Space Research, 48, 76), D'Ammando et
al. (2011, Journal of Physics Conference Series, 280, 012002),
D'Ammando et al. (2010, 38th COSPAR Scientific Assembly, 38, 2240)
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Byte-by-byte Description of file: photom.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Source name
13 A1 --- Filt [VRIJHK] Filter
15- 19 I5 d MJD Modified Julian Date of observation
21- 26 F6.3 mag mag Magnitude in Filt (1)
28- 32 F5.3 mag e_mag Magnitude error
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Note (1): nightly weighted averaged apparent magnitude
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Acknowledgement:
Angella Sandrinelli, angela.sandrinelli( at )brera.inaf.it
(End) Angella Sandrinelli [Universita' dell'Insubria, Como] 14-Jul-2013