J/ApJS/237/30 6-yr light curves of 10 blazars (Meng+, 2018)
Multi-color optical monitoring of 10 blazars from 2005 to 2011.
Meng N., Zhang X., Wu J., Ma J., Zhou Xu
<Astrophys. J. Suppl. Ser., 237, 30 (2018)>
=2018ApJS..237...30M 2018ApJS..237...30M
ADC_Keywords: BL Lac objects; QSOs; Photometry; Optical; Spectroscopy
Keywords: BL Lacertae objects: general ; galaxies: active ; galaxies: photometry
Abstract:
We carried out multi-color optical monitoring of a sample of 10
blazars from 2005 to 2011. The sample contains 3 LBLs, 2 IBLs, 4 HBLs,
and 1 FSRQ. Our monitoring focused on the long-term variability and
the sample included nine BL Lac objects and one flat-spectrum radio
quasar (FSRQ). A total of 14,799 data points were collected. This is
one of the largest optical databases for a sample of 10 blazars. All
objects showed significant variability except for OT 546. Because of
the low sampling on each single night, only BL Lacertae were observed
to have intraday variability on 2006 November 6. Most BL Lac objects
showed a bluer-when-brighter (BWB) chromatism, while the FSRQ, 3C
454.3, displayed a redder-when-brighter trend. The BWB color behaviors
of most BL Lacs can be at least partly attributed to the trend of
increasing variation amplitude with increasing frequency observed in
these objects. The average spectral index of LBLs is around 1.5, as
expected from the model dominated by synchrotron self-Compton loss.
The optical emission of HBL is probably contaminated by the thermal
emission from the host galaxies. Correlation analysis did not reveal
any time delay between variations at different wavelengths.
Description:
Our monitoring program was performed with a 60/90cm Schmidt telescope
located at the Xinglong Station of the National Astronomical
Observatories, Chinese Academy of Sciences (NAOC). This telescope is
equipped with 15 intermediate-band filters, covering the wavelengths
from 300 to 1000nm.
Five filters were adopted for our multi-color quasi-simultaneous
observation:
---------------------------------------
Filter Central Wavelength Bandwith
(Å) (Å)
---------------------------------------
c 4206 289
e 4885 372
i 6685 514
m 8013 287
o 9173 248
---------------------------------------
In our program, 10 blazars were monitored from 2005 January 29 to 2011
June 13. The observation details of our targets are listed in Table 2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
blazars.dat 125 36 Observation details of the 10 objects (table 2) and
Galactic extinction in each band (table 4)
lc.dat 72 14916 Light curves for all 36 observations of the blazars
(compilation from the separated files
in apjsaacffet3_mrt.tar.gz, by CDS)
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Description of file: On the FTP, apjsaacffet3_mrt.tar.gz contains the original
68 files in mrt and ascii for each object in one band and an associated
ReadMe file.
See also:
J/A+AS/109/267 : Radio to X-Ray distribution of BL Lac Objects (Giommi+, 1995)
J/AJ/112/628 : BATC Color Survey of M67 (Fan+ 1996)
J/A+AS/130/109 : BV(RI)c photometry of ON 231 (Tosti+ 1998)
J/ApJ/537/101 : Optical Study for blazars. I. (Fan+, 2000)
J/A+AS/143/357 : Tuorla Quasar Monitoring (Katajainen+ 2000)
J/A+AS/144/481 : BVRI photometry of 5 X-ray selected BL Lacs (Villata+, 2000)
J/A+A/395/11 : BV(RI)c photometry of ON 231 during outburst (Tosti+, 2002)
J/A+A/397/361 : 15-color BATC photometry of Landolt SA95 field (Zhou+, 2003)
J/A+A/450/39 : BVRI photometry of 8 red blazars (Gu+, 2006)
J/MNRAS/373/209 : BATC eim photometry of BL Lac (Hu+, 2006)
J/A+A/445/441 : SED of BL Lacertae objects (Nieppola+, 2006)
J/ApJS/185/511 : Optical microvariability of S5 0716+714 (Poon+, 2009)
J/ApJ/716/30 : SED of Fermi bright blazars (Abdo+, 2010)
J/ApJ/712/405 : Multiwavelength obs. of 3C 454.3 III. (Vercellone+, 2010)
J/ApJS/192/12 : Photometry of the blazar PKS 0537-441 (Impiombato+, 2011)
J/AJ/143/108 : B'V'R' photom. of the BL Lac object S5 0716+714 (Wu+, 2012)
J/A+A/562/A79 : Variability of 7 blazars in six bands (Sandrinelli+, 2014)
J/ApJS/218/18 : 2004-2012 BVRI obs. of blazar S5 0716+714 (Dai+, 2015)
J/AJ/150/67 : Optical photometry for 1ES 1959+650 (Yuan+, 2015)
J/ApJS/226/20 : X-ray, opt. & radio SEDs of Fermi blazars (Fan+, 2016)
Byte-by-byte Description of file: blazars.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Name Blazar name
14 I1 --- n_Name [1/2]? Phase number
16- 17 I2 h RAh Hour of right ascension (J2000)
19- 20 I2 min RAm Minute of right ascension (J2000)
22- 26 F5.2 s RAs Second of right ascension (J2000)
28 A1 --- DE- Sign of declination (J2000)
29- 30 I2 deg DEd Degree of declination (J2000)
32- 33 I2 arcmin DEm Arcminute of declination (J2000)
35- 38 F4.1 arcsec DEs Arcsecond of declination (J2000)
40- 44 F5.3 --- z [0.03/0.9] Redshift
46- 49 A4 --- Type Blazar type (flat-spectrum radio quasar or
BL Lac object with high-, intermediate-, or
low-frequency-peak)
51 A1 --- Band Observation band (see the "Description"
section above for the central wavelengths)
53- 63 A11 "Y/M/D" Stdate Start UT date
65- 75 A11 "Y/M/D" Enddate End UT date
77- 79 I3 --- Nd [5/248] Number of observing days
81- 84 I4 --- Ndata [23/1790] Number of measurements
86- 90 F5.3 mag Ac [0.08/1.3]? c-band extinction
92- 96 F5.3 mag Ae [0.06/1.1]? e-band extinction
98-102 F5.3 mag Ai [0.04/0.7]? i-band extinction
104-108 F5.3 mag Am [0.03/0.5]? m-band extinction
110-114 F5.3 mag Ao [0.02/0.4]? o-band extinction
116-125 A10 --- AName Abbreviated name as used in lc.dat;
column added by CDS
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Byte-by-byte Description of file: lc.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- AName Blazar designation
12 A1 --- Band Observation band (c, e, i, m or o);
see the "Description" section above
14- 23 A10 "Y/M/D" Obs.date UT observation date
25- 34 A10 "h:m:s" Obs.time UT observation time
36- 48 F13.5 d JD Julian Observation date
50- 52 I3 s Exp [20/900] Exposure time
54- 59 F6.3 mag mag [0.3/17.8] Observation magnitude in Band
61- 65 F5.3 mag e_mag [0/0.5] Uncertainty in mag
67- 72 F6.3 mag dfmag [-0.3/0.7] Differential magnitude of
the check star
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 01-Oct-2018