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arXiv · 2004.10500

Unveiling the physical conditions in NGC 6910

Harmeen Kaur·Saurabh Sharma·Lokesh K. Dewangan·Devendra K. Ojha·Alok Durgapal·Neelam Panwar
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Abstract

Deep and wide-field optical photometric observations along with multiwavelength archival datasets have been employed to study the physical properties of the cluster NGC 6910. The study also examines the impact of massive stars to their environment. The age, distance and reddening of the cluster are estimated to be $\sim$4.5 Myr, $1.72\pm0.08$ kpc, and $ E(B-V)_{min}= 0.95$ mag, respectively. The mass function slope ($Γ= -0.74\pm0.15$ in the cluster region is found to be flatter than the Salpeter value (-1.35), indicating the presence of excess number of massive stars. The cluster also shows mass segregation towards the central region due to their formation processes. The distribution of warm dust emission is investigated towards the central region of the cluster, showing the signature of the impact of massive stars within the cluster region. Radio continuum clumps powered by massive B-type stars (age range $\sim$ 0.07-0.12 Myr) are traced, which are located away from the center of the stellar cluster NGC 6910 (age $\sim$ 4.5 Myr). Based on the values of different pressure components exerted by massive stars, the photoionized gas associated with the cluster is found to be the dominant feedback mechanism in the cluster. Overall, the massive stars in the cluster might have triggered the birth of young massive B-type stars in the cluster. This argument is supported with evidence of the observed age gradient between the cluster and the powering sources of the radio clumps.

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Harmeen Kaur, Saurabh Sharma, Lokesh K. Dewangan, Devendra K. Ojha, Alok Durgapal, Neelam Panwar. 2020-04-22. Unveiling the physical conditions in NGC 6910. https://doi.org/10.3847/1538-4357%2Fab9122

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