| 其他摘要 | Massive binary contains at least an early-type star whose spectral type is O, B-type. These binaries have high-energy radiation such as X-rays, and they perhaps create neutron stars or black holes. This proved a valuable chance to study the special astrophysical phenomenon. Due to the limitation of detailed observation and analysis of massive binaries, the formation and evolution of massive binaries are still poorly understood. The nearby Andromeda galaxy (M31) is the closest spiral galaxy to the Milky Way and the largest galaxy in the Local Group. Its structure and metallicity are very close to that of the Milky Way. The international surveys have found many high-quality eclipsing binaries in M31. However, these eclipsing binaries lacked analysis in detail. The questions, such as how they form, how they evolve, and whether their structural characteristics and evolutionary state are the same as those of massive binary stars in the Milky Way, are unsolved. We performed a series of analyses of the massive eclipsing binary in M31 for the first time. Studying the formation and evolution of the massive eclipsing binary in galaxy M31 and comparing it with that of the Milky Way, could provide a valuable test of the evolutionary models of the early OB-type binaries in different galaxies.Since M31 is far away from the earth, most of the eclipsing binaries in M31 are massive binaries. In this paper, firstly, the candidates of massive semi-detached binaries and contact binaries were selected. Then the basic physical parameters of these binaries were determined with the W-D method, and all the minima of these binaries were derived. There are 30 massive semi-detached and contact binaries discovered from 437 eclipsing binaries. Meanwhile, to compare the similarities and differences of the massive binaries, three massive binaries were selected from the Milky Way, namely v606 Cen in the southern sky, ZZ Cas and V375 Cas in the northern sky. The results are as follows:1. By analyzing the light curves and orbital period changes of V606 Cen, ZZ Cas, and V375 Cas, which indicate that V606 Cen is a newly formed massive contact binary and just forms the contact configuration for the mass transfer in a hierarchical triple system. ZZ Cas and V375 Cas are semi-detached binaries in which the secondary components fulfill the critical Roche lobe with the third bodies, and the third body of V375 Cas is a massive main-sequence star, while that of ZZ Cas is possible a low-mass triple system. ZZ Cas and V375 Cas are undergoing a late case A mass transfer from the less massive component to the more massive one. Their periods of the third body are 88.3, 19.1 and 118.7 yr for V606 Cen, ZZ Cas and V375 Cas, respectively. The facts suggest that the third body plays an important role in the formation and evolution of the massive close binaries by extracting angular momentum.2. By the photometric analysis of the massive eclipsing binaries in M31, three massive twin binaries were found, and their mass ratios are close to 1. Two systems are contact binaries with mass ratios of 0.981 and 0.961, and the other system is semi-detached binaries with a mass ratio of 0.935. To our knowledge, the progenitors of these semi-detached binaries are the detached binaries where the original more massive components evolve faster and fill their critical Roche lobes first, and then transfer mass to their companions with the case A evolution. During this process, the orbital period of the system will be decreased and the mass ratio will be increased. When the system evolves to the critical state where the mass ratio is equal to 1, the orbital period of the system is the shortest. Based on the study of the stellar evolutionary tracks and isochrones and the analysis of hot-spot, it is discovered that the evolution stage of two twin contact binaries is about to enter the critical evolution stage of the shortest period. The semi-detached binary has experienced that evolution stage.3. In M31, 19 semi-detached binaries whose secondary components fill their Roche lobes have been found, and their mass ratios and temperature ratios are less than 1. From the relationship of mass ratios and the fill-out factors of the primary stars, it is revealed that they are in the stage of slow mass transfer from less massive components to their companions. which is similar to that of ZZ Cas and V375 Cas in the Milky Way. The symmetric light curves can be explained by the hot-spots, which are caused by the flow of the accreted material from the donor.4. In M31, 5 semi-detached binaries whose primary components fill their Roche lobes have been found. The primary components have high temperatures than the secondary components in the two systems, which reveals that they are created by mass transfer from the primary to the secondary. While there are three systems whose secondary components have higher temperatures, which may reveal that their low massive stars are in the stage of losing part of the hydrogen shell.5. In M31, 3 shallow contact binaries, 2 intermediate contact binaries and 1 deep contact binary have been found, and they are total-eclipsing massive binaries with the mass ratios of 0.476 to 0.981. The fill-out factors of the shallow contact binaries are 5.1-8%, and the mass ratios are ~0 5, which are possibly similar to V606 Cen in the Milky May. 6. The statistical results in M31, show that their mass ratios are mainly in the range of 0.5-0.6, accounting for ~37%. And the temperature ratios are mainly in the range of 0.7-0.8, accounting for 40%. The trend of semi-detached binaries in M31 is very similar to that of the semi-detached binaries in the Milky May. The distributions of the periods of semi-detached binaries and contact binaries from the two galaxies are also similar, both of which follow the logarithmic normal distribution. So that The evolution of massive binaries between different galaxies may be consistent. |
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