bright supernova alert NGC6217 - spectrum needed

Information about outbursts of eruptive stars, Be activity, ...
Post Reply
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

bright supernova alert NGC6217 - spectrum needed

Post by Robin Leadbeater »

Patrick Wiggins reports a bright (mag 14.2) possible supernova in NGC6217
https://wis-tns.weizmann.ac.il/object/2018gj
A low resolution spectrum could confirm this.

Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Olivier GARDE
Posts: 1243
Joined: Thu Sep 29, 2011 6:35 am
Location: Rhône Alpes FRANCE
Contact:

Re: bright supernova alert NGC6217 - spectrum needed

Post by Olivier GARDE »

Hi Robin,

Thanks for this information but actually in south East of France, the weather is not very find....
LHIRES III #5, LISA, e-Shel, C14, RC400 Astrosib, AP1600
http://o.garde.free.fr/astro/Spectro1/Bienvenue.html
etienne bertrand
Posts: 1040
Joined: Mon Aug 31, 2015 11:26 am

Re: bright supernova alert NGC6217 - spectrum needed

Post by etienne bertrand »

Gelato classe cette SN comme une SN de type IIb avec une phase de ~6 jours

Image

Image

Le champ de ciel :
Image

C'est vraiment de la chance car toute la journée la météo a été nuageuse et ventée puis un peu dégagé vers 18h. L'année commence bien. Merci Robin pour l'alerte.
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: bright supernova alert NGC6217 - spectrum needed

Post by Robin Leadbeater »

Thanks Etienne,

SNID predicts a type IIP but with reduced confidence (rlap =3.7 compared with 5.0 for a reliable classification ) see attached SNID best fit

Cheers
Robin
Attachments
2018gj_2458133_2929.png
2018gj_2458133_2929.png (43.78 KiB) Viewed 11909 times
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
etienne bertrand
Posts: 1040
Joined: Mon Aug 31, 2015 11:26 am

Re: bright supernova alert NGC6217 - spectrum needed

Post by etienne bertrand »

Thanks Robin for the alerte.
It's a very lucky time for the weather.
For the type of SN it's possible that is a type IIP. I think it's interesting to take a new spectra in many days or 1 week. If the weather 'll good i take spectra of 1800s for a better SNR.
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: bright supernova alert NGC6217 - spectrum needed

Post by Robin Leadbeater »

Hi Etienne,

Yes early type II are difficult. The spectrum should develop stronger Balmer lines later.

Cheers
Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: bright supernova alert NGC6217 - spectrum needed

Post by Robin Leadbeater »

Type II classification now also confirmed
by professionals using the FLOYDS spectrograph on Faulkes telescope North
http://www.astronomerstelegram.org/?read=11172
https://wis-tns.weizmann.ac.il/object/2018gj

Congratulations to Patrick for the discovery and Etienne for the quick spectroscopic confirmation on TNS. Another “all amateur” supernova !

Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Paolo Berardi
Posts: 578
Joined: Thu Sep 29, 2011 10:51 pm

Re: bright supernova alert NGC6217 - spectrum needed

Post by Paolo Berardi »

Great job Etienne! A success on a very difficult object.
Very useful the Robin assistance.

Paolo
etienne bertrand
Posts: 1040
Joined: Mon Aug 31, 2015 11:26 am

Re: bright supernova alert NGC6217 - spectrum needed

Post by etienne bertrand »

Merci pour vos messages.
En fin de nuit après des étoiles Be j'ai tenté de reprendre cette supernova. Malheureusement le ciel s'est couvert et est devenu très opaque, le signal reçu n'est pas bon. A refaire pour avoir un meilleur signal.
Image

Ha arrive à 6401.5A
Donc la vitesse de l'éjecta :
Vitesse ejecta = (((L1 - L0) / L0) x c) - V helio - V NGC6217
Vitesse ejecta = (((6401.5 - 6562.8) / 6562.8) x 299792.458) - 3.382 - 1363
Vitesse ejecta = - 8734 km/s

Image

Image
Image
Post Reply