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J/other/NewA/55.13  UY UMa and EF Boo compiled time of minima        (Yu+, 2017)

Orbital period variations of two W UMa-type binaries: UY UMa and EF Boo. Yu Y.-X., Zhang X.-D., Hu K., Xiang F.-Y. <New Astron., 55, 13-16 (2017)> =2017NewA...55...13Y (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing Keywords: stars: binaries: close - stars: binaries: eclipsing - stars: individual: UY UMa - stars: individual: EF Boo Abstract: The orbital period variations of two W UMa-type contact binaries, UY UMa and EF Boo, are analyzed by using all available times of light minimum. It is detected that the general trends of their (O-C) curves show an upward parabolic variation, which reveals their continuous period increases at the rates of dP/dt=2.545x10-7days/yr and dP/dt=2.623x10-7days/yr respectively. Meanwhile, UY UMa also shows a cyclic period variation with a small amplitude of A=0.0026-days superposed on the long-term increase. Due to their contact configurations, the secular period increases are interpreted as a result of mass transfer from the less massive component to the more massive one. The cyclic period variation of UY UMa may be interpreted in terms of either the magnetic activity or the light time effect. Description: In order to construct the (O-C) diagram to analyze the period change of UY UMa, we have performed a careful search for all available times of light minima. A total of 76 times of light minima were collected and listed in Table 2. From the literatures and two well-known databases (i.e., the O-C gateway ( and the Lichtenknecker database of the BAV (, we have collected a total of 75 available times of light minima for EF Boo, which are summarized in Table 3. Objects: ----------------------------------------------- RA (2000) DE Designation(s) ----------------------------------------------- 13 44 36.83 +55 13 18.4 UY UMa = V* UY UMa 14 32 30.54 +50 49 40.7 EF Boo = V* EF Boo ----------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 49 76 All compiled times of light minimum for the contact binary UY UMa table3.dat 49 75 All compiled times of light minimum for the contact binary EF Boo refs.dat 71 69 References
Byte-by-byte Description of file: table2.dat table3.dat
Bytes Format Units Label Explanations
1- 13 F13.5 d HJD Heliocentric Julian date 15- 16 A2 --- Type [I ] Type of minima 18- 23 F6.4 d e_HJD ?=- Error on HJD 25- 27 A3 --- Met Method 29- 36 F8.1 d Epoch Epoch 38- 45 F8.5 --- O-C Observed minus computed residual 47- 49 A3 --- Ref Reference, in refs,dat file
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 3 A3 --- Ref Reference code 5- 23 A19 --- BibCode BibCode 25- 44 A20 --- Aut Author's name 46- 71 A26 --- Com Comments
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Nov-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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