Dr. SHI Xiangdong, Prof. QIAN Shengbang et al., from Yunnan Observatories of the Chinese Academy of Sciences (CAS), reported the study on massive pulsating stars. A total of 155 massive pulsating stars or candidates were detected based on TESS, LAMOST and Gaia data, and further analysis has been done. This result was published in The Astrophysical Journal Supplement Series recently.

Massive stars generally refer to O- and B-type stars, which have the characteristics of high mass, temperature and luminosity. They are related to many important objects and physical processes, such as neutron stars, black holes, supernovae and gravitational-wave events.

Massive pulsating stars are particular objects that can obtain their internal structure information from asteroseismology. Slowly pulsating B (SPB) stars and β Cephei pulsating (BCEP) stars are the only two recognized classes of massive pulsating stars in the upper main sequence. However, limited by observational conditions, only hundreds of such objects have been detected now.

Researchers found 155 OB-type pulsating stars or candidates, including 38 Oe/Be stars, from the data observed by TESS, LAMOST and Gaia, which are almost new. Among the 155 objects, 87 samples are identified as SPB stars, 14 samples are identified as BCEP stars, 52 other targets are identified as candidates of them, and 2 samples are identified as particular objects with the property of both SPB and BCEP stars.

This work also derives the preliminary results of period–luminosity (P-L) relation for SPB and BCEP stars, respectively, and indicates that in addition to the H-R diagram, period–temperature (P-T) and P-L diagrams are also very useful for the classification of SPB and BCEP stars.

The discovery of these targets is very important for understanding the theories of evolution and structure for massive pulsating stars, and reveals the potential for massive pulsating stars to be used as a standard candle to measure distances.

This research was supported by the National Natural Science Foundation of China.

Contact:
SHI Xiangdong
Yunnan Observatories, CAS
Email: sxd@ynao.ac.cn