J/PASP/123/26 Time of Maxima for the SX Phe star XX Cyg (Conidis+ 2011)
Period changes in SX Phoenicis stars. III. XX Cygni.
Conidis G.J., Sadavoy S.I., Maxwell A.J., Delaney P.A., Manzer L.H.
<Publ. Astron. Soc. Pac., 123, 26-33 (2011)>
=2011PASP..123...26C 2011PASP..123...26C
ADC_Keywords: Stars, variable ; Photometry, CCD
Keywords: stars: delta scuti pulsators: SX Phe pulsators ;
stars: times of maxima: photometry
Abstract:
XX Cyg is a High Amplitude δ Scuti star which has been
extensively studied because of its changing period. We present 64 new
times of maxima which have been combined with 174 times of maxima from
literature, in order to give an updated ephemeris and O-C plot for
XX Cyg. Its period, currently found to be 0.134865117(3) days, is
shown to be increasing continuously, which has lead to a new
calculated value of (1/P)(dP/dt)=(1.33±0.09)10-8yr-1
Description:
Newly calculated O-C (observed minus calculated) values for the SX Phe
star, XX Cyg, are combined with all times of maxima available in
literature. The calculated values are generated from the newly
presented linear ephemeris (equation 2). For each time of maxima, the
source from which the maxima was acquired from, the time of maxima in
HJD, the cycle number from our newly presented linear ephemeris, and
the O-C value are presented in the order as just stated.
Objects:
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RA (2000) DE Designation(s)
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20 03 15.6 +58 57 17 XX Cyg = HIP 98737
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 80 238 All O-C values for XX Cyg
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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 Maxima Time of Maximum Light
15- 21 I7 --- Cycle The Cycle Number (1)
23- 32 F10.7 d O-C Observed minus Calculated Value
34- 80 A47 --- Source Reference time of maxima is collected from
(include the 19-digit bibcode)
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Note (1): Calculated from equation 2:
HJDmax = 24730671.1031 + 0.134865117 E
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(End) George James Conidis [York U., Canada] 07-Mar-2011