J/other/NewA/51.59 LY And photometric followup (Lu+, 2017)
Photometric followup investigations on LAMOST survey target LY And.
Lu H.-P., Zhang L.-Y., Han X.L., Pi Q.-F., Wang D.-M.
<New Astron., 51, 59-64 (2017)>
=2017NewA...51...59L 2017NewA...51...59L (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Photometry, UBVRI
Keywords: binaries: close - binaries: eclipsing - stars: period variation -
stars: individual: LY And
Abstract:
We present a low-dispersion spectrum and two sets of CCD photometric
light curves of the eclipsing binary LY And for the first time. The
spectrum of LY And was classified as G2. We derived an updated
ephemeris based on all previously available and our newly acquired
minimum light times. Our analyses of LY And light curve minimum times
reveals that the differences between calculated and observed minimum
times for LY And can be represented by an upward parabolic curve,
which means its orbital period is increasing with a rate of 1.88
(±0.13)x10-7days/year. This increase in orbital period may be
interpreted as mass transfer from the primary component to the
secondary component, with a rate of
dM1/dt=-4.54x10-8M☉/year. By analyzing our CCD
photometric light curves obtained in 2015, we obtained its photometric
solution with the Wilson-Devinney program. This photometric solution
also fits very well our light curves obtained in 2014. Our photometric
solution shows that LY And is a contact eclipsing binary and its
contact factor is f=(17.8±1.9)%. Furthermore, both our
spectroscopic and photometric data show no obvious chromospheric
activity of LY And.
Description:
We obtained our first photometric data set in R and I bands for LY And
on November 24, 2014 using the 1-m RCC reflecting telescope at Yunnan
Observatory, which was equipped with an Andor DW436 2048x2048 CCD
camera with a field of view of 7.3'x7.3'. The exposure times were
300s for both R and I bands.
We obtained our second photometric data set in B, V, R and I bands
using the SARA 914-mm telescope at Kitt Peak National Observatory on
October 23, 2015. This telescope was equipped with a 2048x2048
pixels CCD and each pixel after 2x2 binning is about 0.86". The
exposure times were 120s in B band and 60 s in V, R and I bands,
respectively.
Objects:
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RA (2000) DE Designation(s)
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02 21 52.49 +38 37 42.2 LY And = V* LY And
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 39 50 Original photometric data of LY And observed by
the 1-m RCC reflecting telescope at Yunnan
Observatory on November 24, 2014
table3.dat 79 117 Original photometric data of LY And observed by
the 914-mm SARA telescope at Kitt Peak National
Observatory on October 23, 2015
table5.dat 58 81 Minimum times and their relevant parameters of
LY And
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 13 F13.5 d HJD-R Heliocentric Julian date for R-band
15- 19 F5.3 mag dRmag Differential R magnitude
21- 33 F13.5 d HJD-I ? Heliocentric Julian date for I-band
35- 39 F5.3 mag dImag ? Differential I magnitude
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Byte-by-byte Description of file: table3.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
15- 19 F5.3 mag dBmag Differential B magnitude
21- 33 F13.5 d HJD-V Heliocentric Julian date for V-band
35- 39 F5.3 mag dVmag Differential V magnitude
41- 53 F13.5 d HJD-R Heliocentric Julian date for R-band
55- 59 F5.3 mag dRmag Differential R magnitude
61- 73 F13.5 d HJD-I Heliocentric Julian date for I-band
75- 79 F5.3 mag dImag Differential I magnitude
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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- 13 F13.5 d HJD Heliocentric Julian date
15- 21 F7.5 d e_HJD ? rms uncertainty on HJD
23- 30 F8.1 d Epoch Epoch
32- 34 A3 --- Meth [pg ccd] Method
36- 38 A3 --- Type [pri sec] Type of minima
40 I1 --- Weight [1/5] Weight
42- 48 F7.4 d (O-C)I Observed minus computer for primary minimum
50- 56 F7.4 d (O-C)II Observed minus computer for secondary minimum
58 I1 --- Ref [1/9] Reference (1)
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Note (1): References as follows:
1 = http://var2.astro.cz/EN/; Paschke & Brat 2006
2 = Otero et al. (2006IBVS.5674....1O 2006IBVS.5674....1O )
3 = Brat et al. (2008OEJV...94....1B 2008OEJV...94....1B)
4 = Brat et al. (2011OEJV..137....1B 2011OEJV..137....1B)
5 = Diethelm (2011IBVS.5960....1D 2011IBVS.5960....1D)
6 = Honkova et al. (2013EJV..160....1H)
7 = Diethelm (2012IBVS.6011....1D 2012IBVS.6011....1D)
8 = Diethelm (2013IBVS.6042....1D 2013IBVS.6042....1D)
9 = This paper
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 13-Apr-2017