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arXiv · 2204.00248

Study of Classical Be stars in open clusters older than 100 Myr

Madhu Kashyap Jagadeesh·Blesson Mathew·K. T. Paul·Gourav Banerjee·Annapurni Subramaniam·R. Arun
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Abstract

We performed the slitless spectroscopic survey to identify Classical (CBe) stars in open clusters older than 100 Myr. Observing a sample of 71 open clusters, we identified 13 CBe stars in 11 open clusters, one of, which (TYC 2679-432-1) is a new detection. The 13 CBe stars show both H$\alpha$ in emission and IR excess, which confirm that they possess gaseous circumstellar discs. Two more CBe stars are found to exhibit H$\alpha$ in absorption for the first time, indicating that might be passing through disc-less episode presently. The spectral type estimation is done for all these 15 stars and it is noticed that they belong to B0.5 -- B8 type. Moreover, we found that the distribution of our sample is peaking near late B-types as expected.

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Madhu Kashyap Jagadeesh, Blesson Mathew, K. T. Paul, Gourav Banerjee, Annapurni Subramaniam, R. Arun. 2022-04-01. Study of Classical Be stars in open clusters older than 100 Myr. https://doi.org/10.1007/s12036-021-09780-w

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