The Catalina Surveys Periodic Variable Star Catalog

Abstract

With the discovery of the first transiting extrasolar planetary system back in 1999, a great number of projects started to hunt for other similar systems. Because the incidence rate of such systems was unknown and the length of the shallow transit events is only a few percent of the orbital period, the goal was to monitor continuously as many stars as possible for at least a period of a few months. Small aperture, large field of view automated telescope systems have been installed with a parallel development of new data reduction and analysis methods, leading to better than 1% per data point precision for thousands of stars. With the successful launch of the photometric satellites CoRoT and Kepler, the precision increased further by one-two orders of magnitude. Millions of stars have been analyzed and searched for transits. In the history of variable star astronomy this is the biggest undertaking so far, resulting in photometric time series inventories immensely valuable for the whole field. In this review we briefly discuss the methods of data analysis that were inspired by the main science driver of these surveys and highlight some of the most interesting variable star results that impact the field of variable star astronomy.

Understanding extreme quasar optical variability with CRTS – I. Major AGN flares

“…This relation was derived from 100 000 isotropically selected sources that exhibited no significant sign of variability based on their Welch-Stetson variability index. However, errors at the brighter magnitudes are overestimated and those at fainter magnitudes (>18) are underestimated (Palaversa et al 2013;Drake et al 2014;Vaughan et al 2016). We have derived a multiplicative correction factor from CRTS observations of 350 000 sources in the Stripe 82 Standard Star catalogue (Ivezic et al 2007) that ensures that the mode of the reduced chi-squared variability in magnitude bins of width of mag = 0.05 is centred at unity (see Fig.…”

The Catalina Surveys Southern periodic variable star catalogue

“…In Drake et al (2013a,b) and Torrealba et al (2015), we targeted type-ab RR Lyrae variables, and later extended our search to investigate all types of periodic variable sources in CSS data. In Drake et al (2014a;DR14 hereafter), we explored the Northern data (δ > −20 • , hereafter CSS-N).…”

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

“…Since binary light curves are normally represented by two sine waves, therefore, multiplying the period by a factor of two gives the true period of the binary system. We therefore assigned a period of 0.266402±0.000018 days for the binary system, which is in accordance with the period obtained by Drake et al (2014). In the following equation, we draw the ephemeris for the minimum light as a function of the binary star.…”

“…Drake et al (2014) first reported this star as a W UMa contact binary having a period of 0.266398 days and reported a V band amplitude of 0.54 mag. In our analysis, we carried out period analysis using Period04 (Lenz & Breger 2005).…”

“…We determined a mean magnitude of 16.867 mag and 16.470 mag in R c and I c bands, respectively. The mean magnitude estimation through the phase-weighted method was preferred as this method minimizes the systematic biases due to loss of measurements towards fainter magnitudes (Saha & Hoessel, 1990 Drake et al (2014). The 2MASS JHK magnitudes are given as 14.345, 14.009, and 13.847 mag, respectively (Cutri et al 2003).…”