Long-term V-band monitoring of the bright stars of M33 at the Wise Observatory

Abstract

Abstract We have conducted a long-term V-band photometric monitoring of M33 on 95 nights during four observing seasons (2000–2003). A total number of 6418 light curves of bright objects in the range of 14–21 mag have been obtained. All measurements are publicly available. A total of 127 new variables were detected, of which 28 are periodic. 10 previously known non-periodic variables were identified as periodic, three of which are Cepheids, and another previously known periodic variable was identified as an eclipsing binary. Our derived periods range from 2.11 to almost 300 d. For 50 variables we have combined our observations with those of the DIRECT project, obtaining light curves of up to 500 measurements, with a time-span of ∼7 yr. We have detected a few interesting variables, including a 99.3 d periodic variable with a 0.04 mag amplitude, at the position of supernova remnant (SNR) 19.