FINDING PERIODIC VARIABLE IN THE NSVS

 

The Northern Sky Variability Survey was searched for periodic variables. Periods were searched from 0.01 -365 days for all light curves with 20 points or more.  Two distinct methods were used: the string/rope (S-L) length method based on the Lafler-Kinman statistic (Clarke, D. 2002 A&A, 386, 763) and the analysis of variance method (AoV) (Schwarzenberg-Czerney, A. 1989, MNRAS, 241,153). Of the over 17 million light curves with more than 20 points deemed ‘good’ data by the NSVS, over 84000 were found to have periodicity.  Since the NSVS contains some duplicate light curves the actual number of stars with suspected periodic variability is somewhat fewer than that.

 

Over 13000 of these light curves have been inspected by eye to refine the periodicity and to assign a type of variability.  These are in typed.cat.Z while those not looked at are in untyped.cat.Z.  More information on the catalog is in README.doc or README.txt.

 

I would like to thank all of those who assisted in this endeavor. (Listed with the institution they were at during their contribution,)

Jeffery Coughlin (Emory University)

Susan Chung (University of Georgia)

Cece Hedrick (University of Nebraska)

David Hou (Athens Academy)

Nicole Kelley (U. of California, Berkeley)

Travis McIntyre (Clemson University)

Yelena Pelimskaya (Lehigh University)

Christine Shaw (Athens Academy)

 

Searches targeted at specific types of variables in the NSVS also resulted in new members of rare types of variable stars

 

Near Contact Binaries

 

Eclipsing Binaries with subdwarf B (sdB) stars

 

Cool Algols

 

GS Binaries (eclipsing systems with both components a subgiant or giant star)