J/AJ/141/65 BATC ceimo light curves of OJ 287 (Dai+, 2011)
Color behavior of BL Lacertae object OJ 287 during an optical outburst.
Dai Y., Wu J., Zhu Z.-H., Zhou X., Ma J.
<Astron. J., 141, 65 (2011)>
=2011AJ....141...65D 2011AJ....141...65D
ADC_Keywords: BL Lac objects ; Photometry
Keywords: BL Lacertae objects: individual (OJ 287) - galaxies: active -
galaxies: photometry
Abstract:
This paper studies the color behavior of the BL Lac object OJ 287
during an optical outburst. Upon revisiting the data from the OJ 94
monitoring project, and from an analysis of the data obtained with the
60/90cm Schmidt Telescope of NAOC, we found a bluer-when-brighter
chromatism in this object. The amplitude of variation tends to
decrease with frequency. These results are consistent with the
shock-in-jet model. We ran some simulations and confirmed that both
amplitude difference and time delay between variations at different
wavelengths can result in the bluer-when-brighter phenomenon. Our
observations confirmed that OJ 287 underwent a double-peaked outburst
about 12 years after 1996, which provides further evidence for the
binary black hole model in this object.
Description:
Our optical monitoring program of OJ 287 was performed with a 60/90cm
Schmidt telescope located at the Xinglong Station of the National
Astronomical Observatories of China (NAOC).
This paper includes data from 2005 January 29 to 2009 April 13.
Excluding nights with bad weather and those devoted to other targets,
the actual number of nights for OJ 287 observations was 234.
Objects:
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RA (2000) DE Designation(s)
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08 54 48.87 +20 06 30.6 OJ 287 = QSO J0854+2006
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 61 252 Data of BATC c (421.0nm) band
table3.dat 61 227 Data of BATC e (492.5nm) band
table4.dat 61 329 Data of BATC i (666.0nm) band
table5.dat 61 221 Data of BATC m (802.0nm) band
table6.dat 61 254 Data of BATC o (919.0nm) band
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See also:
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 in 2005-09 (Villforth+, 2010)
Byte-by-byte Description of file: table?.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "YYYY/MM/DD" 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 BATC (AB) magnitude in Filter
48- 52 F5.3 mag e_mag Uncertainty in mag
54- 59 F6.3 mag dfm11 Star 11 BATC differential magnitude (1)
61 A1 --- Filt [ceimo] Observed filter
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Note (1): The nightly averages were set to be zero.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 28-Jul-2012