Alpha Camelopardalis

[jsandse]

Hi all,
I am going to try and monitor activity on Alpha Camelopardalis over next couple of weeks.
The scientific papers state that this star is very active and I should be able to see profile changes every day
Just wandered if anyone out there has ever studied/observed this star.

My first spectra from last night is attached.

cheers

John

[Olivier Thizy]

John,

this seems an interesting project. De the papers mention which resolving power would be required to see such short-time changes ?

Cordialement,
Olivier Thizy
Vous ne verrez plus des étoiles comme avant !
http://www.shelyak.com/en/

[jsandse]

Paper I was reading was Markova 2002.
The resolution of the spectra taken was 15000 for one set of spectra and 22000 for the other. SNR varied from 50 to 275 for the spectra.

cheers

John

[jsandse]

Ok first comparison of Alpha Cam from two nights ago in blue and last night in pink.

Quite a few noticeable differences...

[Thierry Garrel]

Hi John,
i'm happy that your guest has leaved. So now you're on the right time for gathering spectra during bad weather
Alp Cam seems not to move between your two spectra. What are the narrow peaks you have above the continuum ? Cosmic or Real ?
Amitiés
thierry
Ps:planning a rendez vous one of these night ?

[jsandse]

Preliminary results of my study of Alpha Cam over the last week.
Diagram shows changes in the broad Halpha emission line over 5 nights. The line shape changes from being symmetric to being asymmetric.

I now want to learn how to remove cosmics and tellurics as there are a few of these in the spectra - anyone got any comments on best way of doing this.

cheers

John

[Valerie Desnoux]

Hi
To remove cosmic, it has first to be done during image processing. But if one or two "outliers" remains and if you're using Vspec, you can:
- menu: edit>pixel... see the manual for how to edit the pixel you want
or
- select the region where you have the pixel, try to make it small to not "erase" too much profile, go menu: operations>interpole zone. A new profile is created, if it is ok, then move it as your intensity profile with the use of the button: replace

Valerie

[jsandse]

Thanks for the advice Valerie.

I'll try both suggestions to see which works best.

I have also been experimenting with removing the telluric lines using VSpec

Will post results up once I finally get all the processing done on the spectra

cheers

John

[jsandse]

Another picture this time showing two spectra from 4th Oct in blue and 17th Oct in red of the pretty dramatic changes in the Halpha line of Alpha Cam.

Cheers

John

[Dubreuil Pierre]

Bonsoir

Un spectre de Alp Cam dans L’UV realisé avec UVEX4 fente 15microns.

Spectre AlpCam 3601 to 4242.png (148.32 KiB) Viewed 9595 times

Pierre