Multiband photometric re-classification of ROTSE-I δ Scuti type stars*
Korea Astronomy Observatory, Daejeon 305-348, Korea
2 Department of Astronomy and Space Science, Kyunghee University, Yongin 449-701, Korea
Corresponding author: H. Jin, email@example.com
Accepted: 21 March 2003
We present multi-passband CCD photometry of 20 ROTSE-I δ Scuti type pulsating stars and 1 RR Lyrae star to re-classify their variable types using the comparison of amplitudes between V and I passbands. For the re-classification, we used a criterion that pulsating stars have larger amplitude differences between passbands than eclipsing binaries because brightness changes of pulsating stars are mainly due to the temperature variations. As a result, only six stars were re-confirmed as δ Scuti variables and thirteen stars turned out to be W UMa type eclipsing binaries. The other two stars were identified as one cataclysmic variable and one non-variable, respectively. Our results suggest that a number of ROTSE-I δ Scuti type stars, which do not show typical pulsating light curves of high amplitude δ Scuti stars, are W UMa type eclipsing binaries.
Key words: stars: variables: δ Sct / stars: binaries: eclipsing / techniques: photometric
© ESO, 2003