Access to Astronomical Catalogues

← Click to display the menu
J/AJ/110/1350                Beta Lyrae light curve changes (Van Hamme+ 1995)

Periodic light curve changes for Beta Lyrae Van Hamme W., Wilson R.E., Guinan E.F. <Astron. J. 110, 1350 (1995)> =1995AJ....110.1350V
ADC_Keywords: Stars, variable ; Photometry Abstract: We apply a variety of classical and recently developed periodicity analyses to light curves of Beta Lyrae in 9 eras that extend over a range of about 150 years. Some new data are tabulated. Most periodic variations that have been reported in the literature do not pass standard significance tests, according to our adopted criteria. Certain other periods do pass the tests, although most do so only for one, or at most two, data sets. Our main findings are that a period of about 9 months is present in all data sets and that it connects extremely well in phase from era to era, all the way back to Baxendell's observations of 1840-1877. The semiamplitude is small but reasonably consistent, averaging about 2% of the flux in the light curve maxima. Any substantially larger excursions that occur are nonperiodic. Phase coherence of the 9 month period is fairly good, even with a linear ephemeris, and becomes excellent if one allows for a slow sinusoidal variation of the 9 month periodicity. There is some evidence for a monotonic decrease in the amplitude of the 9 month periodicity with increasing wavelength. Description: Tables 2-5 present the original observations made with the 38cm reflector at Villanova (VIL) and the 25cm automated photoelectric telescope (APT), located on Mount Hopkins, Arizona. All differential magnitudes are with respect to the comparison star Gam Lyr. The Halpha and Hbeta filters are broad, with full width at half maximum (FWHM) 29 and 18 nm, respectively. The effective wavelengths are 660 and 487 nm. The Balmer lines presumably have only minor influences on these rather wide bandpasses. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 18 36 55.4 +38 46 47 alpha Lyr = HD 172167 = HR 7001 18 50 04.7 +33 21 46 beta Lyr = HD 174638 = HR 7106 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2 23 1246 beta Lyrae Villanova Halpha (wide) observations table3 23 668 beta Lyrae Villanova Hbeta (wide) observations table4 23 544 beta Lyrae Villanova Stromgren y observations table5.dat 54 899 beta Lyrae APT observations
Byte-by-byte Description of file: table2 table3 table4
Bytes Format Units Label Explanations
1- 13 F13.5 d HJD1 Heliocentric Julian Date 16- 22 F7.4 mag dm Differential magnitude
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 12 F12.4 d HJD Heliocentric Julian Date 14- 19 F6.3 mag dVmag []? Differential V mag (Var. - Comp.) 21- 26 F6.3 mag dRmag []? Differential R mag (Var. - Comp.) 28- 33 F6.3 mag dImag []? Differential I mag (Var. - Comp.) 35- 40 F6.3 mag dVc []? Differential V mag (Check - Comp.) 42- 47 F6.3 mag dRc []? Differential R mag (Check - Comp.) 49- 54 F6.3 mag dIc []? Differential I mag (Check - Comp.)
Origin: AAS CD-ROM series, Volume 5, 1995 Lee Brotzman [ADS] 28-Sep-1995
(End) [CDS] 25-Jan-1996
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

catalogue service

© Unistra/CNRS