A Search For R Coronae Borealis Type Stars in the All-Sky Automated Survey for Supernovae

Session Number

Project ID: PHYS 19

Advisor(s)

Aaron A. Geller; Northwestern University, Adler Planetarium

Adam A. Miller; Northwestern University, Adler Planetarium

Discipline

Physical Science

Start Date

22-4-2020 8:50 AM

End Date

22-4-2020 9:05 AM

Abstract

We present the results of an analysis of a search for R Coronae Borealis (RCB) type stars using cataloged light curves from the All-Sky Automated Survey for Supernovae (ASAS-SN), parallax and colour data from Gaia, and Infrared photometry from the Wide-field Infrared Survey Explorer (WISE). RCB stars—carbon rich, extremely hydrogen deficient supergiants—are of immense interest as these stars provide important insight into the late stages of stellar evolution. These stars exhibit up to ~8 magnitude dips in brightness. With their high variability, one would expect these stars to be easy to find and classify. However, there are only ~65 classified RCB stars in our galaxy, despite a predicted ~5000. The discrepancy in these numbers suggests a bias in current RCB search methods. In light of this, we employ a simple search procedure that allows us to rapidly identify candidates while searching for RCB stars. With this process we were able to quickly identify 30 known RCB stars, and identify a previously unclassified RCB candidate. We consider these results, derived from cuts based upon data from ASAS-SN, AllWISE, and Gaia, to demonstrate an efficient and effective algorithm for the discovery of these rare sources.

Share

COinS
 
Apr 22nd, 8:50 AM Apr 22nd, 9:05 AM

A Search For R Coronae Borealis Type Stars in the All-Sky Automated Survey for Supernovae

We present the results of an analysis of a search for R Coronae Borealis (RCB) type stars using cataloged light curves from the All-Sky Automated Survey for Supernovae (ASAS-SN), parallax and colour data from Gaia, and Infrared photometry from the Wide-field Infrared Survey Explorer (WISE). RCB stars—carbon rich, extremely hydrogen deficient supergiants—are of immense interest as these stars provide important insight into the late stages of stellar evolution. These stars exhibit up to ~8 magnitude dips in brightness. With their high variability, one would expect these stars to be easy to find and classify. However, there are only ~65 classified RCB stars in our galaxy, despite a predicted ~5000. The discrepancy in these numbers suggests a bias in current RCB search methods. In light of this, we employ a simple search procedure that allows us to rapidly identify candidates while searching for RCB stars. With this process we were able to quickly identify 30 known RCB stars, and identify a previously unclassified RCB candidate. We consider these results, derived from cuts based upon data from ASAS-SN, AllWISE, and Gaia, to demonstrate an efficient and effective algorithm for the discovery of these rare sources.