J/AJ/149/111 BRI light curves of 2MASS J02272637+1156494 (Liu+, 2015)
First photometric solution of a very short period contact binary below the
period limit.
Liu L., Chen W.P., Qian S.B., Chuang R.J., Jiang L.Q., Lin C.S., Hsiao H.Y.
<Astron. J., 149, 111 (2015)>
=2015AJ....149..111L 2015AJ....149..111L
ADC_Keywords: Binaries, eclipsing ; Photometry, UBVRI
Keywords: binaries: close - binaries: eclipsing - stars: evolution -
stars: individual: 2MASS J02272637+1156494
Abstract:
The star 1SWASP J022727.03+115641.7 was reported as a contact binary
with a period shorter than the empirical limit of such systems. Our
study shows the star not to be variable. Instead, it is the nearby
star, 2MASS 02272637+1156494, that exhibits variability. The BRI CCD
light curves of 2MASS 02272637+1156494 show the system to be a
moderate mass ratio (2.154-0.074+0.008), and shallow contact
(10.4-1.9+1.4%) W-type contact binary. The masses, radii, and
luminosities of the binary components are, respectively,
M1=0.25-0.01+0.05M☉, M2=0.54-0.04+0.11M☉,
R1=0.45-0.01+0.02R☉, R2=0.63-0.02+0.04R☉,
L1=0.038-0.005+0.018L☉, and
L2=0.071-0.010+0.037L☉, with an estimated distance
326-46+127 pc. These uncertainties mainly come from the errors of
the colors used to estimate the temperature of the primary star. A
dark spot was introduced on the massive component in the final
solution.
Description:
The field of 2MASS J02272637+1156494 was observed for three nights
(2013 September 7, 9, 11) with the Lulin One-meter Telescope (LOT) of
the National Central University in Taiwan, located at
120°52'25''E, 23°28'07''N, and at an altitude of 2862m. A
PI1340*1300 B CCD was used, with the standard UBVRI filter set, that
gave an effective FOV of about 11.5*11.2arcmin2. For the data
reported here, the integration times for the images were 120s in the
BRI bands.
Objects:
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RA (ICRS) DE Designation(s) (Period)
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02 27 26.37 +11 56 49.4 2M 0227+1156 = 2MASS J02272637+1156494 (P=0.21095)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 21 191 The original data of 2MASS 02272637+1156494
observed in the BRI bands by the Lulin One-meter
Telescope (LOT)
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See also:
I/297 : NOMAD Catalog (Zacharias+ 2005)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/528/A90 : SuperWASP short period eclipsing binaries (Norton+, 2011)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.5 d HJD Heliocentric Julian Date (HJD-2456500)
10- 14 F5.3 mag Dmag [-0.085/1.349] Δ magnitude
16- 19 F4.3 mag e_Dmag Uncertainty in Dmag
21 A1 --- Flt [BRI] Filter (B, R, or I)
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History:
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 25-Mar-2015