Astronomers find 19 new Wolf-Rayet stars in the Andromeda Galaxy

And a new paper published on the arXiv preprint server claims that astronomers from the Harvard-Smithsonian Center for Astrophysics (CfA) and Lowell Observatory in the United States: 19 bright, hot, massive stars found according to Wolf-Rayet (WR) classification. Initially, the category was chosen because of the 1867 discoveries by scientists Étienne Wolf and Georges-Antoine-Pons Rayet.

The discovery was made using data collected during observations by the Lowell Discovery Telescope (LDT) telescope in Arizona.. The stars were found somewhere advanced stage of evolution, with large nuclei rapidly losing mass; They are located in the Andromeda Galaxy.

Scientists have found a few other WR stars in the Andromeda Galaxy, but most have been found in our own Milky Way. The new study used data from the Large Monolithic Imager (LMI), an equipment installed at LTD.

Wolf-Rayet stars are concentrated only in their birthplaces, so searching for WRs in the vast expanse of the universe can be difficult.

“From these discoveries, we estimate that there are about 60 more WRs to be discovered in M31; however, the overall proportion of WN-type (nitrogen-rich) WC-type (carbon-rich) WRs has remained unchanged with our recent additions to the M31 WR count. We are in the process of expanding the WR survey to include the remainder of M31, and a more complete population will be detailed in our future studies,” concludes the study.

Wolf-Rayet Stars

After collecting the data for the first time, the scientists believed they had found about 30 WRs; They then performed a detailed spectroscopic analysis and confirmed 19 stars via the MMT telescope operated by the Multiple Mirror Telescopic Observatory (MMTO).

The authors state that 19 WR is fainter than other stars detected with the same classification., therefore, they were not noticed in previous research. Either way, astronomers suggest that many more Wolf-Rayet stars are waiting to be found.

“Our enhanced imaging data and spectroscopic tracking have confirmed 19 new WRs in three small areas in M31. These newly discovered WRs are generally weaker than the previously known sample due to slightly increased redness against intrinsic fainting,” he explains.

Scientists note that most of the WR stars have not yet been found due to the lack of sensitivity of the observing equipment. They believe that the Andromeda Galaxy must also be home to another 60 Wolf-Rayet as yet unidentified and will therefore continue to work to identify them.