TYC 2428-695-1 a possible new Be Star ?

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Robin Leadbeater
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TYC 2428-695-1 a possible new Be Star ?

Post by Robin Leadbeater »

mag 10 TYC 2428-695-1 has been flagged by Gaia in TNS as rising by 0.3 mag. (AT 2022eoq)
https://www.wis-tns.org/object/2022eoq
A low resolution spectrum by amateur Claudio Balcon posted on TNS shows a spectrum with a blue continuum consistent with a B star with H alpha in emission and other Balmer lines in absorption. A high resolution spectrum of the H alpha line could provide more information on this new emission line star.

Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: TYC 2428-695-1 a possible new Be Star ?

Post by Robin Leadbeater »

From the (B-V) -0.19 in SIMBAD this is consistent with ~B4 without extinction.
From the Gaia parallax the distance is ~2200pc
Using this and the 11 apparent V mag in SIMBAD gives an absolute V mag of ~-0.7 which rules out a giant star and is consistent with a ~B6v star (from Gray and Corbally)
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: TYC 2428-695-1 a possible new Be Star ?

Post by Robin Leadbeater »

A high resolution (R~14000) spectrum of the H alpha emission line taken using the LHIRES III shows a "bottle shaped" profile (FWHM 150km/s, EW -25 Angstrom) consistent with a circumstellar disc (J. Silaj et al 2010 ApJS 187 228 https://iopscience.iop.org/article/10.1 ... /187/1/228 )
tyc2428-695-1_20220316_865_Leadbeater.png
tyc2428-695-1_20220316_865_Leadbeater.png (20.24 KiB) Viewed 3031 times
It seems likely therefore that this is a previously unknown Be star. The spectrum has been uploaded to TNS and the BAA database

Cheers
Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
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