new Be star ABE-98 HD219523 is NOT in emission

[Robin Leadbeater]

I took a look at HD219523 last night (high resolution H alpha). It is another of the 128 newly published Be stars (ABE-98)
http://arxiv.org/abs/1409.4668
http://www.spectro-aras.com/forum/viewt ... =920#p4177

I was surprised to find no evidence of emission.
The original paper measured the H 11 Brackett line in the IR, not H alpha. Has the activity changed since the spectrum in the paper was taken? (only one spectra was taken of this object by the APOGEE team) or can Be stars show Brackett line emission but no emission at H alpha?

Cheers
Robin

[Andrew Smith]

Hi Robin, your result prompts some interesting questions. The review paper by Rivinius et. al. "Classical Be stars" 2013 defines a necessary but not sufficient requirement as being "A non-supergiant B star whose spectrum has, or had at some time, one or more Balmer lines in emission." The "Blamer lines" replacing the original "hydrogen lines" of Jaschek 1981. So on the current definition the work done in the paper you sight does not allow for the identification of classical Be stars! However, as it got past the referees they must know something I don't. I think we will need an expert to comment further.

Are you planning to check them all?

Regards Andrew

[Robin Leadbeater]

Hi Andrew,

I dont plan doing a systematic survey of them but I thought I might dip in to them occasionally when I have time. Eventually I expect they will be included in BeSS/ARAS Beam and routinely monitored. Attached is the Br11 line profile from their spectrum. (from table 19 - "weak or ambiguous emission profile type") A double peaked emission is clearly there in the photospheric absorption line, though not very strong. Perhaps it has since gone into quiescence.

Cheers
Robin