J/AJ/148/110 BATC ceimo light curves of 1ES 0806+52.4 (Man+, 2014)
Six-year optical monitoring of the BL Lacertae object 1ES 0806+52.4.
Man Z., Zhang X., Wu J., Zhou X., Yuan Q.
<Astron. J., 148, 110 (2014)>
=2014AJ....148..110M 2014AJ....148..110M
ADC_Keywords: BL Lac objects ; Galaxies, photometry
Keywords: BL Lacertae objects: individual: 1ES 0806+524 - galaxies: active -
galaxies: photometry
Abstract:
We present the results of the first systematic long-term multicolor
optical monitoring of the BL Lacertae object 1ES 0806+52.4. The
monitoring was performed in multiple passbands with a 60/90cm Schmidt
telescope from 2005 December to 2011 February. The overall brightness
of this object decreased from 2005 December to 2008 December but was
regained after that. A sharp outburst probably occurred around the end
of our monitoring program. Overlapping the long-term trend are some
short-term small-amplitude oscillations. No intranight variability was
found in the object, which is in accordance with the historical
observations before 2005. By investigating the color behavior, we
found a strong bluer-when-brighter chromatism for the long-term
variability of 1ES 0806+52.4. The total amplitudes at the c, i, and o
bands are 1.18, 1.12, and 1.02mag, respectively. The amplitudes tend
to increase toward shorter wavelengths, which may be a major cause of
the bluer-when-brighter chromatism. Such bluer-when-brighter
chromatisms are also found in other blazars, such as S5 0716+714, OJ
287. The hard-X-ray data collected from the Swift/BAT archive was
correlated with our optical data. No positive result was found, the
reason for which may be that the hard-X-ray flux is a combination of
the synchrotron and inverse Compton emission, but with different
timescales and cadences under the leptonic synchrotron self-Compton
model.
Description:
Our observations were performed using the 60/90cm Schmidt telescope
at the Xinglong Station of the National Astronomical Observatories of
China (NAOC). Mounted at the telescope main focus was a Ford Aerospace
2048*2048 thick CCD camera, which was then surrogated by a new E2V
4096*4096 CCD in 2006 December.
Our monitoring program on 1ES 0806+52.4 started on the night of 2005
December 12 and ended on 2011 February 11. Four stars, C1, C2, C3, and
C4, were selected as reference stars, and we choose star C5 as a check
star.
Objects:
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RA (ICRS) DE Designation(s)
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08 09 49.19 +52 18 58.3 1ES 0806+52.4 = QSO B0806+524
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 59 292 Observational log and results in the c band (0.42um)
table3.dat 59 150 Observational log and results in the e band (0.49um)
table4.dat 59 490 Observational log and results in the i band (0.66um)
table5.dat 59 171 Observational log and results in the m band (0.80um)
table6.dat 59 296 Observational log and results in the o band (0.92um)
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See also:
II/262 : BATC Data Release One - BATC DR1 (Zhou+ 1995-2005)
J/AJ/143/108 : B'V'R' photometry of the BL Lac object S5 0716+714 (Wu+, 2012)
J/AJ/141/65 : BATC ceimo light curves of OJ 287 (Dai+, 2011)
J/AJ/132/1256 : eim BATC photometry of OJ 287 (Wu+, 2006)
J/AJ/129/1818 : Photometry of S5 0716+714 (Wu+, 2005)
J/A+A/397/361 : 15-color BATC photometry of Landolt SA95 field (Zhou+, 2003)
J/AJ/117/2757 : Surface photometry of NGC 5907 (Zheng+, 1999)
J/AJ/112/628 : BATC Color Survey of M67 (Fan+ 1996)
Byte-by-byte Description of file: table[23456].dat
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Bytes Format Units Label Explanations
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1- 10 A10 "Y:M:D" Obs.date UT date of the observation
12- 21 A10 "h:m:s" Obs.time UT time of the observation
23- 35 F13.5 d JD Julian Date of the observation
37- 39 I3 s Exp Exposure time
41- 46 F6.3 mag mag The magnitude (1)
48- 52 F5.3 mag e_mag Error in mag
54- 59 F6.3 mag Dmag Differential magnitude (2)
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Note (1): In c-band for table2, in e-band for table3, in i-band for table4,
in m-band for table5, and in o-band for table6.
Note (2): The difference between the magnitude (in c, e, i, m, or o band
according to the table) of C5 and the average magnitude of the four
reference stars (C1, C2, C3, and C4). The nightly averages were set to zero.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 09-Dec-2014