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Call for observations on 3 Clasical Be stars: Omi And, Phi A

Posted: Fri Aug 03, 2018 4:57 am
by Olivier Thizy
Hello,

here a request rom a professional astronomers team to monitor three taregt with the goal to trigger follow up observations with different instruments in case of discovered outburst:

We would like to request one spectrum per night to be taken for each of the 3 targets at resolution at least 10000, and containing the H-alpha line. As this monitoring is meant as a potential trigger for follow up observations, we ask that the spectra are submitted to the BeSS website as soon as possible after they are taken. We are looking for a sudden increase in line emission or a sudden onset of line wings asymmetry in a previously symmetric profile (i.e., signs an outburst - an ejection of material from the star into its surroundings). In case you can detect a clear increase in emission as compared to the spectra taken previously, please also send an e-mail to robertklement@gmail.com and to the BeSS valid team at webmaster.BeSS@obspm.fr. Thank you!


Cordialement,
Olivier

Re: Call for observations on 3 Clasical Be stars: Omi And, P

Posted: Sat Aug 04, 2018 1:28 am
by Olivier Thizy
Hello,


thank you to all of you that are currently participating to this campaign. It has been interesting for the last few days as we noticed some evolution on lam Cyg and of course this brought some excitements:
Capture.JPG
Capture.JPG (117.77 KiB) Viewed 4107 times

We of course alerted the team that initiated this campaign but it turned out that they are looking for a bigger "bang" :-)

As Robert K wrote us: "these updates are very useful. For our purposes we believe that the rise in emission would need to be more dramatic, but in any case, nice catch!"

I am not sure the reason behind those small changes: spot on the (rotating) star? non radial pulsations? small ejection of matter?

In any case, let's continue to observe lam Cyg but also omi And and phi And. Such monitoring over several months could certainly bring some more information on those stars specially if we can provide high frequency observations. Observers from all region (R>10000, Halpha) are more than welcometo participate as we need to spread the risk of bad weather (we are very lucky at the moment but it won't last for months!)...


Cordialement,
Olivier

Re: Call for observations on 3 Clasical Be stars: Omi And, P

Posted: Sat Aug 18, 2018 11:30 am
by Joan Guarro Flo
Hi to all,

I think that the 12 Vul, (HD187811), is another of Be stars that also enter this campaign of monotorisation.
12 Vul presents a "periodic" growth on the blue side of the absorption lines such as Halpha and Heli at 5875.65 A. This line also seems double.
Differences may appear to be minimal, but they may be imperative for further analysis.
Do you need more observations, do you encourage yourself?

Regards, Joan.