双星与变星研究组知识库

We analyzed the B and V light curves of two EA-type binaries V211 and NV358 for the first time using the Wilson-Devinney code. Our analysis shows that V211 is a typical Algol-type binary and NV358 is a well detached binary system. As the two binaries are definite members of omega Centauri due to their proper motion, we estimated their physical parameters, obtaining M-1 = 1.13 +/- 0.03 M-circle dot, R-1 = 0.98 +/- 0.01 R-circle dot, M-2 = 0.33 +/- 0.01 M-circle dot and R-2 = 0.92 +/- 0.01 R-circle dot for V211; M-1 = 1.30 +/- 0.05 M-circle dot, R-1 = 1.03 +/- 0.01 R-circle dot, M-2 = 0.58 +/- 0.02 M-circle dot and R-2 = 0.78 +/- 0.01 R-circle dot for NV358. On the color-magnitude diagram of omega Centauri, V211 is located in the faint blue straggler region and its primary component is more massive than a star at the main-sequence turnoff. Therefore, V211 is a blue straggler and was formed by mass transfer from the secondary component to the primary. The age of NV358 is less than 1.93 Gyr, indicating that it is much younger than the first generation of stars in omega Centauri. Like NV364 in omega Centauri, NV358 should be a second-generation binary.