J/other/NewA/51.1 AS CrB BVRI light curves (Liu+, 2017)
First four-color photometric investigation of extreme mass-ratio contact binary
AS Coronae Borealis.
Liu L., Qian S., Zhu L., Liao W., He J., Liu N.
<New Astron., 51, 1-6 (2017)>
=2017NewA...51....1L 2017NewA...51....1L (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Photometry, UBVRI
Keywords: binaries: close - stars: binaries: eclipsing -
Stars: individuals (AS coronae borealis)- stars: evolution
Abstract:
The first high-precision BVRI light curves of the eclipsing binary AS
CrB were presented and were analyzed by the 2015 version of the W-D
code. It is found that AS CrB is an extreme mass-ratio, deep contact
binary with a fill-out factor of f=59.6±2.5% and a mass ratio of
q=0.172±0.008q=0.172±0.008. Based on the photometric solution and
the Dartmouth isochrones model, the masses, radii, and luminosities of
the components are estimated as follows: M1=1.25±0.15M☉,
M1=1.25±0.15M☉, M2=0.21±0.06M☉,
M2=0.21±0.06M☉, R1=1.40±0.07R☉,
R1=1.40±0.07R☉, R2=0.67±0.04R☉,
R2=0.67±0.04R☉, L1=3.2±0.2L☉,
L1=3.2±0.2L☉, and L2=0.72±0.04L☉,
L2=0.72±0.04L☉, with an estimated distance 459±42pc. These
uncertainties mainly come from the errors of the color used to
estimate the temperature of the primary star. By investigating all of
the available times of light minima, it is found that the
Observed-Calculated [(O-C)(O-C)] curve shows a long-term period
increase, with a rate of
dP/dt=+(3.46±0.01)x10-7dP/dt=+(3.46±0.01)x10-7day/year. As an
extreme mass-ratio contact binary, AS CrB may merge into a single
star, such as an FK Com-type star or a blue straggler, because of the
orbital instability.
Description:
To investigate the variation of the orbital period, we had observed AS
CrB with the 1m and 60cm reflecting telescopes at the Yunnan
Observatories (YNOs), and with the 85 cm reflecting telescope at the
Xinglong Station, the National Astronomical Observatory (NAO).
Objects:
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RA (2000) DE Designation(s)
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16 00 14.51 +35 12 31.6 AS CrB = V* AS CrB
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables1.dat 91 353 The original data of AS CrB in BVRI passband
observed by 85-cm telescope at Xinglong Station
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Byte-by-byte Description of file: tables1.dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d HJD-B Heliocentric Julian date for B-band observation
15- 20 F6.3 mag dBmag Differential B magnitude
22 A1 --- B [B]
24- 36 F13.5 d HJD-V ? Heliocentric Julian date for V-band observation
38- 43 F6.3 mag dVmag ? Differential V magnitude
45 A1 --- V [V]
47- 59 F13.5 d HJD-R ? Heliocentric Julian date for R-band observation
61- 66 F6.3 mag dRmag ? Differential R magnitude
68 A1 --- R [R]
70- 82 F13.5 d HJD-I ? Heliocentric Julian date for I-band observation
84- 89 F6.3 mag dImag ? Differential I magnitude
91 A1 --- I [I]
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 31-Mar-2017