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HD189847 in emission

Posted: Wed Sep 24, 2014 9:53 pm
by Andrew Smith
I find HD189847 / HIP98525 to be in emission. I can't find it in Bess database and Simbad has it as B7V. From a quick look at the references I see no indication of emission. I am now clouded out.

I also find the star HD192445 / HIP99667 to show emission in H alpha and H beta.

See attached

Regards Andrew

Re: HD189847 in emission

Posted: Wed Sep 24, 2014 9:55 pm
by Robin Leadbeater
Confirmed (LHIRES 2400)

Robin

Re: HD189847 in emission

Posted: Wed Sep 24, 2014 9:56 pm
by Andrew Smith
Please note I misslabled the images. The text has the correct star numbers.

Regards Andrew

Re: HD189847 in emission

Posted: Wed Sep 24, 2014 10:12 pm
by Robin Leadbeater
Hi Andrew,

It looks like you have just been beaten to this discovery by a week :cry: This paper published on ArXiv lists HD189847 (and HD40724 and 126 other stars) as a new Be stars
http://arxiv.org/abs/1409.4668
see 3.4

That is really bad luck but it does show the capability of your system

Robin

Re: HD189847 in emission

Posted: Thu Sep 25, 2014 3:57 am
by Francois Teyssier
As Robin said, you got a great result Andrew. Let's go on !

Here's two papers which can help ou you in your Quest.

The frequency of Be Stars, Jaschek, 1983
http://adsabs.harvard.edu/abs/1983A%26A...117..357J

Classification of Be Stars, Jaschek, 1980
http://adsabs.harvard.edu/abs/1980A%26AS...42..103J

Also,
Here's an excel spreadsheet : list of non giant B stars ( V < 10) from Simbad
http://www.astronomie-amateur.fr/Docume ... ibles.xlsm

All the best,

François

Re: HD189847 in emission

Posted: Thu Sep 25, 2014 5:48 am
by Andrew Smith
Thanks Robin & Francois, I am sure there will be more to find. The weather here has been unusually kind but it looks set to change.

Regards Andrew

Re: HD189847 in emission

Posted: Thu Sep 25, 2014 10:15 am
by Robin Leadbeater
I see from the discovery paper they intend adding their spectra to BeSS at some stage

"the full
data set will be made publicly-available in SDSS data re-
lease 12 (DR12: scheduled for December 2014). Shortly
after DR12, we intend to convert the APOGEE Be star
spectra to the format accepted by the Be Star Spectra
Database (BeSS; Neiner et al. 2011) and deposit them
there, ensuring convenient public access."

In the meantime, HD189847 could be worth keeping an eye on though even if it is not yet in BeSS yet as according to the paper it was not in emission in 2000

(Bjorkman, K. S., & Miroshnichenko, A. S. 2000, Bulletin of the American Astronomical Society, 32, 1480)

so could go back to quiescence at any time.

Robin

EDIT - sorry this reference is a "red herring" They were speculating that HD189847 may not have previously been in emission, like delta Sco which was first discovered in emission in 2000.

Still worth keeping an eye on though

Robin

Re: HD189847 in emission

Posted: Fri Sep 26, 2014 10:32 am
by Andrew Smith
I have analysed the paper Robin unearthed and of the new Be stars 12 are in my current search magnitude range (5.5 to 7.5). This compares to 270 in the current BeSS data base an addition of about 4.5%. I think there are still more to find and will continue to search.

Regards Andrew

Re: HD189847 in emission

Posted: Fri Sep 26, 2014 1:53 pm
by Christian Buil
A spectrum of HD189847 taken last night at high resolution (R=50000) - (VHIRES-MO + C11 + 50 microns fiber fed):

Image

Some "official" Be stars Halpha spectra taken during the same night and the same setup (note typical bottle profiles):

beta Psc:

Image

48 And:

Image

31 Peg:

Image

phi And:

Image

V442 And (outburst dtectect by Valerie Desnoux this spring):

Image

Christian

Re: HD189847 in emission

Posted: Fri Sep 26, 2014 2:20 pm
by Andrew Smith
Nice spectra Christian, any chance you could capture HD181751 ? Thanks Andrew