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This year CBAT have stopped accepting supernova discoveries without supporting spectroscopic evidence. This is giving problems for amateur supernova hunters. I have been approached by a couple of leading UK amateurs in this field to see what amater spectroscopists could do. While it is proving possible for amateurs to take low resolution R~600 spectra of bright supernovae down to around mag 15, I am looking for more specific information about what MINIMUM resolution and SNR is needed for this task. (I have feeling based on some experience with crude slitless SNe spectra that this might be possible with R ~200 or even lower but it would be nice to have confirmation from an expert) Does anyone know or have contacts with anyone who might know?

Thanks
Robin

Hello Robin

This could be of interesst: http://www.eso.org/~bleibund/

Bruno Leibundgut is the specialist at ESO. I send him your mail and ask him for help



Daniel Sablowski




Von: Robin Leadbeater <fg-spek-convento@vds-astro.de>
An: fg-spek-convento@vds-astro.de
Gesendet: Mittwoch, den 20. Juli 2011, 16:46:36 Uhr
Betreff: [fg-spek] spectroscopically classifying supernovae

This year CBAT have stopped accepting supernova discoveries without supporting spectroscopic evidence. This is giving problems for amateur supernova hunters. I have been approached by a couple of leading UK amateurs in this field to see what amater spectroscopists could do. While it is proving possible for amateurs to take low resolution R~600 spectra of bright supernovae down to around mag 15, I am looking for more specific information about what MINIMUM resolution and SNR is needed for this task. (I have feeling based on some experience with crude slitless SNe spectra that this might be possible with R ~200 or even lower but it would be nice to have confirmation from an expert) Does anyone know or have contacts with anyone who might know?

Thanks
Robin

_________________
Daniel P. Sablowski

https://www.kunstmann.de/buch/axel_hack ... 42000/t-2/
https://dpsablowski.wordpress.com
https://github.com/DPSablowski
https://www.aip.de/mitglieder/dsablowski/

Hallo,

ich habe eine Antwort von Herrn Leibundgurt bekommen:


>Lieber Herr Sablowski,

Vielen Dank fuer Ihre freundliche Anfrage.

Typical emsission velocities of supernovae is around 20000 to 30000
km/s. Hence the resolution should be good enough to resolve these lines.
This implies that resolutions of a few hundred are typically very good
for supernova spectroscopy as they resolve the lines with a few
resolution elements. In principle, resolutions down to 100 are okay, but
at this point there are only few resolution elements across a single
line. A resolution of 200 is probably more than adequate for early
phases of supernovae. After maximum, Type Ia Supernovae
start to display lines from slower material and hence a resolution of a
couple hundred is probably preferable.

There are many spectral series on supernovae published (and freely
available) and they could probably help as guidelines.

Ich hoffe, dass das ein wenig weiter hilft. Ich bin leider im Moment
unterwegs und habe keine Moeglichkeit etwas Literatur zusammen zu
stellen. Eine Suche nach "Supernova spectroscopy" hat folgenden Link
gegeben: http://www.springerlink.com/content/v21834411107n421/
Das Buch hat den Titel "Supernovae and How To Observe Them" und hat ein
Kapitel "Supernova Spectroscopy" mit einigen nuetzlichen Hinweisen. Es
scheint frei zugaenglich zu sein.

Mit freundlichen Gruessen,
Bruno Leibundgut.

_________________
Daniel P. Sablowski

https://www.kunstmann.de/buch/axel_hack ... 42000/t-2/
https://dpsablowski.wordpress.com
https://github.com/DPSablowski
https://www.aip.de/mitglieder/dsablowski/

Thank you Daniel,

That is very useful. Please pass on my thanks to Bruno Leibundgut. At 200 resolution I think we have a real chance to be able to do something useful using an efficient spectrograph and a sensible amateur aperture.

Cheers
Robin


----- Original Message ----- From: Daniel Sablowski (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Saturday, July 23, 2011 7:50 AM
Subject: [fg-spek] Re: spectroscopically classifying supernovae



Hallo,

ich habe eine Antwort von Herrn Leibundgurt bekommen:

Vielen Dank fuer Ihre freundliche Anfrage.

Typical emsission velocities of supernovae is around 20000 to 30000
km/s. Hence the resolution should be good enough to resolve these lines.
This implies that resolutions of a few hundred are typically very good
for supernova spectroscopy as they resolve the lines with a few
resolution elements. In principle, resolutions down to 100 are okay, but
at this point there are only few resolution elements across a single
line. A resolution of 200 is probably more than adequate for early
phases of supernovae. After maximum, Type Ia Supernovae
start to display lines from slower material and hence a resolution of a
couple hundred is probably preferable.

There are many spectral series on supernovae published (and freely
available) and they could probably help as guidelines.

Ich hoffe, dass das ein wenig weiter hilft. Ich bin leider im Moment
unterwegs und habe keine Moeglichkeit etwas Literatur zusammen zu
stellen. Eine Suche nach "Supernova spectroscopy" hat folgenden Link
gegeben: http://www.springerlink.com/content/v21834411107n421/
Das Buch hat den Titel "Supernovae and How To Observe Them" und hat ein
Kapitel "Supernova Spectroscopy" mit einigen nuetzlichen Hinweisen. Es
scheint frei zugaenglich zu sein.

Mit freundlichen Gruessen,
Bruno Leibundgut.



Daniel Sablowski

Das Gegenteil einer jeden Wahrheit ist falsch, das Gegenteil einer tiefen Wahrheit ist wieder eine tiefe Wahrheit.
[Bohr]

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