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HD 184061, a possible Be star?
Posted: Mon Oct 19, 2015 6:32 pm
by Paolo Berardi
Hi all, yesterday I had the opportunity to observe the bright star HD 184061 in Aquila (Hipparcos catalog 96092), finding an H-alpha profile type often exhibited by Be stars (central emission on a photospheric large absorption).
On Simbad the object type is 'Star', with spectral type A0 and no luminosity class reported. The Catalogue of Stellar Spectral Classifications (Skiff, 2009-2014) reports only one entry with spectral type B9.5IV-V and no note about an emission line status. The star seems not included in BeSS stars list.
Firstly, I would like to ask a confirmation of its peculiarity or not. Eventually, could anybody take a new spectrum? Just to exclude a mistake in my observation.
If real, might it be classified as Be Star, taking into account the star properties?
The star field:
Paolo
Re: HD 184061, a possible Be star?
Posted: Mon Oct 19, 2015 9:50 pm
by Hubert Boussier
Buonasera Paolo,
Ho guardato HD184061, Paolo hai ragione c'è una righa d'èmissione nella righa di assorbimento Halpha.
Pero sul Simbad il classo spettralo é A0
Buona notte
Hubert
Re: HD 184061, a possible Be star?
Posted: Mon Oct 19, 2015 10:44 pm
by Paolo Berardi
Thanks a lot for your confirmation Hubert!
Merci beaucoup et bonne nuit a vous aussi.
Paolo
Re: HD 184061, a possible Be star?
Posted: Tue Oct 20, 2015 10:19 am
by Hubert Boussier
Bonjour,
Le spectre basse résolution de l'étoile HD184061 pour laquelle Paolo a détecté un raie Halpha en émission.
Le spectre global LISA – Atik 460EX 2x2, C11 Edge f/D 0,7 15x15s:
La raie Halpha
Hubert
Re: HD 184061, a possible Be star?
Posted: Wed Oct 21, 2015 1:31 pm
by Andrew Smith
Hi Paolo, well done were you looking for Be type stars specifically?
Can you and Herbert send your FITS file to Thierry Lemoult for adding to his database here
http://www.astrosurf.com/aras/be_candid ... idate.html
Regards Andrew
Re: HD 184061, a possible Be star?
Posted: Wed Oct 21, 2015 9:23 pm
by Paolo Berardi
Very nice spectrum, Hubert. The h-alpha profile is well-resolved.
Andrew, thank you for reminding me the excellent job of data collection carried out by Thierry. I just sent him my spectrum.
It would be very useful a specialist opinion.
I wasn't following a Be search plan, the observation was by chance enough...
Paolo
Re: HD 184061, a possible Be star?
Posted: Sat Oct 24, 2015 6:28 pm
by Thierry Lemoult
Hello
Nice finding Paolo. I just updated the page
http://www.astrosurf.com/aras/be_candid ... idate.html with this new possible Be star.
Thierry
Re: HD 184061, a possible Be star?
Posted: Sun Oct 25, 2015 7:12 pm
by Paolo Berardi
Thierry, Andrew, I read "To Be or not to Be" section, you are doing a great job.
For HD184061, also the H-K color seems ok, being equal to +0.03. The luminosity class value is missing on Simbad (but an old paper reports IV-V), so I tried to observe the star in a spectral region with sensible lines. Luminosity effect is shown on "A Digital Spectral Classification Atlas" by R. O. Gray:
https://ned.ipac.caltech.edu/level5/Gra ... tents.html
Luminosity effect at A0 (Gray page) and, below, the same spectral region for HD 184061 and Vega observed with Lhires III and 1200 l/mm grating:
From these spectra (but consider my untrained eye!), the star HD 184061 seems to fall between III and V class. Supergiants class association should be excluded because of the low metal lines strength and broadened Balmer lines (if that is a density effect).
Yesterday I took an R~6000 spectrum of H-alpha line:
Paolo
PS: Thierry, I'm sending you the profiles for the database.
Re: HD 184061, a possible Be star?
Posted: Sun Oct 25, 2015 9:38 pm
by Andrew Smith
Paolo - Skiff's (2009 -2014) Catalogue of Stellar Classification here
http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/mk has it as B9.5IV-V so a good candidate for a Be star.
Regards Andrew
Re: HD 184061, a possible Be star?
Posted: Wed Nov 06, 2019 6:26 pm
by Paolo Berardi
Hi all,
some recent hi-res observations better highlight the emission component features.
H-alpha and h-beta lines (17/09/2019 and 26/09/2019):
I observed HD 184061 even during the past years, noting that the profiles remained fairly stable (H-alpha line).
I summarize the complete chronological sequence:
26/09/2019
17/09/2019
12/09/2019
22/09/2016
24/10/2015
23/10/2015 (used for luminosity class check)
17/10/2015
There is also a R=1000 confirmation spectrum by Houbert Boussier (see above in the thread).
Paolo