Physical parameters of 62 eclipsing binary stars using the All Sky Automated Survey-3 data − I

Abstract

We present a detailed light-curve analysis of publicly available V-band observations of 62 binary stars, mostly contact binaries, obtained by the All Sky Automated Survey (ASAS)-3 project between 2000 and 2009. Eclipsing binaries are important astronomical targets for determining the physical parameters of component stars from the geometry of their orbits. They provide an independent direct method of measuring the radii of stars. We improved the ASAS determined periods and ephemerides, and obtained the Fourier parameters from the phased light curves of these 62 stars. These Fourier parameters were used for preliminary classification of the stars in our sample. The phased light curves were then analysed with the aid of the Wilson-Devinney light-curve modelling technique in order to obtain various geometrical and physical parameters of these binaries. The spectroscopic mass ratios as determined from the radial velocity measurements available in the literature were used as one of the inputs to the light-curve modelling. Thus reliable estimations of parameters of these binaries were obtained with combined photometric and spectroscopic data, and error estimates were made using the heuristic scan method. For several systems in the sample, the solutions were obtained for the first time and would serve as a good source in the future for light-curve analysis based on more precise follow-up CCD photometric observations. Out of 62 stars in the sample, photometric analysis of 39 stars is presented here for the first time using the ASAS photometry and precise spectroscopic mass ratios. From the analysis, we found 54 contact binaries, six semidetached binaries and two detached binaries. The Fourier parameters in the a 2 -a 4 plane were used for preliminary classification, and the final classification was done based on the Roche lobe geometry obtained from the light-curve modelling.

Magnetic Activity and Period Variation Studies of the Short-period Eclipsing Binaries. II. V1101 Her, AD Phe, and NSV 455 (J011636.15–394955.7)

“…We successfully explained the asymmetry in its light curves. The spectroscopic mass ratio is q=0.378, which is similar to the results obtained by Duerbeck & Rucinski (2007) and Deb & Singh (2011). The orbital inclination is 76°.05(±0.08), which is close to the results (72°.8∼75°.0) of McFarlane & Hilditch (1987) and 74°.0 by Deb & Singh (2011).…”

“…In 2007, Duerbeck & Rucinski (2007) carried out a medium precision radial velocity observation and obtained a spectroscopic mass ratio as q=0.37 (±0.01) for the system. Deb & Singh (2011) analyzed a V-band light curve observation obtained by the All Sky Automated Survey (ASAS). They obtained the physical parameters of AD Phe.…”

Long-term photometric study of a faint W UMa binary in the direction of M31

“…Lifang Li et al (2004) have discussed a model for contact binaries with a low total mass, where binary star evolves into a system with smaller mass-ratio and deeper envelope and concluded that some of the A-subtype contact binaries observed with low total mass could be W-subtype binaries in their later evolutionary stages. In order to understand any such transition in the presently studied W UMa binary, we draw mass-ratio versus period for the binary systems in Figure 8, and also overplotted the parameters of ∼ 300 contact binaries detected in several previous studies including many low mass A-subtypes and W-subtypes W UMa binaries (Pribulla et al, 2003;Deb & Singh, 2011;Eker et al, 2013;Yildiz & Dogan, 2013). The position of the binary system CSS J004259.3 + 410629 in the plot indicates its possible transition from W-subtype to A-subtype while undergoing a decrease in mass-ratio via magnetic braking through angular momentum loss and it may continue to evolve into a single star through merger.…”

“…Deb & Singh (2011) recently analysed light curves of 62 binary stars, of which most of them were contact binaries, and found a good correlation between the period and infra-red (J − K) colour as following (J − K) = (0.11 ± 0.01)P −1.19±0.08…”

Absolute Parameters and Physical Nature of the Low-Amplitude Contact Binary Hi Draconis

“…Although the heuristic scan (Prša & Zwitter 2005a) is a Monte Carlo (MC) parameter scan that uses minimization methods for many iterations, each time updating the input parameter values determined in the previous iteration (Maceroni et al 2009;Deb & Singh 2011), we additionallyused the MC analysis by creating many artificial data sets from the observations with the same noise as observations, and analyzing them as before. As expected, the random displacement of the original data (3000 data sets for each filter were created) follows a normal distribution with a zero mean and the standard deviation of the observations in each filter.…”