J/ApJS/185/511 Optical microvariability of S5 0716+714 (Poon+, 2009)
The optical microvariability and spectral changes of the BL Lacertae
object S5 0716+714.
Poon H., Fan J.H., Fu J.N.
<Astrophys. J. Suppl. Ser., 185, 511-525 (2009)>
=2009ApJS..185..511P 2009ApJS..185..511P
ADC_Keywords: BL Lac objects ; Photometry, UBVRI
Keywords: BL Lacertae objects: individual (S5 0716+714) - galaxies: active
galaxies: photometry
Abstract:
We monitored the BL Lac object S5 0716+714 in the optical band during
2008 October and December and 2009 February with a best temporal
resolution of about 5 minutes in the BVRI bands. Four fast flares were
observed with amplitudes ranging from 0.3 to 0.75mag. The source
remained active during the whole monitoring campaign, showing
microvariability in all days except for one. The overall variability
amplitudes are ΔB∼0.89, ΔV∼0.80, ΔR∼0.73, and
ΔI∼0.51mag. Typical timescales of microvariability range from 2
to 8hr. The overall V-R color index ranges from 0.37 to 0.59.
Strong bluer-when-brighter chromatism was found on internight
timescales. However, a different spectral behavior was found on
intranight timescales. A possible time lag of ∼11 minutes between B
and I bands was found on one night. The shock-in-jet model and
geometric effects can be applied to explain the source's intranight
behavior.
Description:
Our photometric observations were carried out at the 85cm telescope
located at the Xinglong Station of the National Astronomical
Observatories of China (NAOC). This telescope is equipped with a
standard Johnson-Cousin-Bessel multicolor CCD photometric system.
Objects:
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RA (2000) DE Designation(s)
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07 21 53.4 +71 20 36 S5 0716+714 = 8C 0716+714
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 26 586 Observational data for S5 0716+714 (B filter)
table2.dat 26 1441 Observational data for S5 0716+714 (V filter)
table3.dat 26 1436 Observational data for S5 0716+714 (R filter)
table4.dat 26 707 Observational data for S5 0716+714 (I filter)
table5.dat 44 41 Results of microvariability of BL Lacertae
S5 0716+714
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See also:
J/A+A/327/61 : BV(RI)c photometry of S5 0716+714 (Ghisellini+ 1997)
J/A+A/402/151 : S5 0716+714 UBVRI photometry (Raiteri+, 2003)
J/AJ/129/1818 : Photometry of S5 0716+714 (Wu+, 2005)
J/A+A/451/435 : BV(RI)c photometry of S5 0716+714 (Montagni+, 2006)
J/AZh/83/310 : BV(RI)c photometry of S5 0716+714 (Amirkhanyan+, 2006)
J/AJ/133/1599 : B'V'R' photometry of S5 0716+714 (Wu+, 2007)
Byte-by-byte Description of file: table[1234].dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d JD Julian Date of observation
15- 20 F6.3 mag mag The B,V,R or I band magnitude
22- 26 F5.3 mag e_mag The 1σ error in mag
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1 A1 --- f_Date [*] Note on Date (1)
2- 11 A10 "DD/MM/YYYY" Date Universal date of observation
13 A1 --- Band [BVRI] Band
15- 19 F5.3 mag Amp ?=- Intranight variability amplitude
21- 23 I3 --- N Number of data points
25- 29 F5.2 --- C Value of the C parameter (Romero et al.,
1999A&AS..135..477R 1999A&AS..135..477R)
31 A1 --- Var [VN] V indicates that the source is
variable
33- 37 F5.3 --- sigma rms error
39- 44 F6.3 --- r ?=- Pearson correlation coefficient of the
V-R color index vs R magnitude
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Note (1): We detected significant brightness changes in a large fraction of
nights: only in 1 night (29/12/2008) marked with an asterisk, the
source remain stable during the observation time window.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 22-Mar-2010