A couple of Wolf Rayet star spectra

Hi all,

I have remounted my cheap diffraction grating (only 20Euro and it is even
blazed!) closer to my long exposure modified surveillance camera to see how
deep I might be able to get. My first target to try it out was a couple of
Wolf Raynet stars (WR 135, 140) nice and easy around mag7-8 but spectra down
to mag 12 were also visible. This is fun!

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

Robin
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Robin Leadbeater
N54.75 W3.24
www.leadbeaterhome.fsnet.co.uk/astro.htm
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"Robin Leadbeater" wrote Hi all,

I have remounted my cheap diffraction grating (only 20Euro and it is even
blazed!) closer to my long exposure modified surveillance camera to see
how
deep I might be able to get. My first target to try it out was a couple of
Wolf Raynet stars (WR 135, 140) nice and easy around mag7-8 but spectra
down
to mag 12 were also visible. This is fun!

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

That's some good stuff! What are the peaks at about 450/460nm and 570nm?
(Ignorant of stellar spectroscopy!)


Martin
--
M.A.Poyser Tel.: 07967
110890
Manchester, U.K.
http://www.fleetie.demon.co.uk

"Fleetie" wrote in message
...
"Robin Leadbeater" wrote Hi all,

I have remounted my cheap diffraction grating (only 20Euro and it is
even
blazed!) closer to my long exposure modified surveillance camera to see
how
deep I might be able to get. My first target to try it out was a couple
of
Wolf Raynet stars (WR 135, 140) nice and easy around mag7-8 but spectra
down
to mag 12 were also visible. This is fun!

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

That's some good stuff! What are the peaks at about 450/460nm and 570nm?
(Ignorant of stellar spectroscopy!)


Probably He II emission lines, very strong in WR stars. Looks like some
other stuff is also present around 5500; N III? With resolution of 3nm it
is hard to tell.

--
Mike Dworetsky

(Remove "pants" spamblock to send e-mail)
..

"Mike Dworetsky" wrote in message
...


"Fleetie" wrote in message
...

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

That's some good stuff! What are the peaks at about 450/460nm and 570nm?
(Ignorant of stellar spectroscopy!)


Probably He II emission lines, very strong in WR stars. Looks like some
other stuff is also present around 5500; N III? With resolution of 3nm it
is hard to tell.

--

I have to confess, I did not take a calibration spectrum so I roughly
calibrated them based on Maurice Gavin's WR 135 spectrum here

http://www.astroman.fsnet.co.uk/wr3.htm

He suggested C III C IV and He II around 4650 and C III C IV at 5700/5810.
He shows two split lines here for a similar dispersion to mine so I have to
learn how to do better. Any ideas about the bump at around 6500? I have a
lot to learn about this lark (probably a lifetimes worth!)

Robin

To be honest, I'd never even heard of this class of star before,
cos I don't know much about any of this, but I just went here

http://www.astroman.fsnet.co.uk/wr.htm

And read that their surface temperature can reach 100,000K in some
cases. OMG! "surface temperature" as in our sun's surface temperature
is only about 6000K? Yeowch, those are some HOT stars.

And up to 50 solar masses?!


Martin
--
M.A.Poyser Tel.: 07967
110890
Manchester, U.K.
http://www.fleetie.demon.co.uk

On Sun, 18 Apr 2004 11:43:35 +0100, "Robin Leadbeater"
wrote:

This is fun!

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

Robin Leadbeater

Well done - glad you're enjoying it!

"Robin Leadbeater" wrote in message
...

"Mike Dworetsky" wrote in message
...


"Fleetie" wrote in message
...

The spectra and more info on the website here

http://www.leadbeaterhome.fsnet.co.u...troscopy_2.htm

That's some good stuff! What are the peaks at about 450/460nm and
570nm?
(Ignorant of stellar spectroscopy!)


Probably He II emission lines, very strong in WR stars. Looks like
some
other stuff is also present around 5500; N III? With resolution of 3nm
it
is hard to tell.

--

I have to confess, I did not take a calibration spectrum so I roughly
calibrated them based on Maurice Gavin's WR 135 spectrum here

http://www.astroman.fsnet.co.uk/wr3.htm

He suggested C III C IV and He II around 4650 and C III C IV at 5700/5810.
He shows two split lines here for a similar dispersion to mine so I have
to
learn how to do better. Any ideas about the bump at around 6500? I have a
lot to learn about this lark (probably a lifetimes worth!)

Robin



Again probably He II, at almost the same wavelength as H-alpha, plus a C IV
line(?). I'm not absolutely sure if you have a WC or WN star. Without a
wavelength calibration things get difficult. On the whole I think you have
WC5 or 6 stars but I could be wrong.

Some information is he

http://nedwww.ipac.caltech.edu/level5/Gray/frames.html

and he

http://nedwww.ipac.caltech.edu/level...as/frames.html

and here

http://cfa-www.harvard.edu/~pberlind.../atframes.html


More information than you can handle in one go is he

http://www.ucm.es/info/Astrof/invest...d/spectra.html

--
Mike Dworetsky

(Remove "pants" spamblock to send e-mail)

"Mike Dworetsky" wrote in message
...


Again probably He II, at almost the same wavelength as H-alpha, plus a C
IV
line(?). I'm not absolutely sure if you have a WC or WN star. Without a
wavelength calibration things get difficult. On the whole I think you
have
WC5 or 6 stars but I could be wrong.



Thanks for the excellent links Mike.
WR140 is class WC8 and WR135 WC7 apparently

Robin