Title: Variable stars in the open cluster NGC 2141 Author: Yanping Luo
We report the results of a search for variable stars in the open cluster NGC 2141. Ten variable stars are detected, among which nine are new variable stars and they are classified as three short period W UMa type eclipsing binaries, two EA type eclipsing binaries, one EB type eclipsing binary, one very short period RS CVn type eclipsing binary, one d type RR Lyrae variable star, and one unknown type variable star. The membership and physical properties are discussed, based on their light curves, positions in the CMDs, spatial locations and periods. A known EB type eclipsing binary is also identified as a blue struggler candidate of the cluster. Furthermore, we find that all eclipsing contact binaries have prominently asymmetric eclipses and O Connell effect (O Connell 1951) which increases with the decrease of the orbital periods. This suggests that the O Connell effect is probably related to the evolution of the orbital period in short period eclipsing binary systems.
NGC 2141 (also Collinder 79 and OCL 487) is a magnitude +9.4 open star cluster located 13,154 light-years away in the constellation Orion.
The open cluster was discovered by American astronomer Edward Emerson Barnard possibly using a 12.7 cm (5 inch) refracting telescope at the Vanderbilt Observatory, Nashville between 1892 and 1884.
Right Ascension 06h 02m 55.0s, Declination +10° 26' 47"