SN 2018cow

Information about outbursts of eruptive stars, Be activity, ...
Post Reply
Peter Somogyi
Posts: 420
Joined: Sun Jul 13, 2014 8:56 am

SN 2018cow

Post by Peter Somogyi »

A very faint object:
http://www.astronomerstelegram.org/?read=11727
http://www.rochesterastronomy.org/sn2018/sn2018cow.html
https://wis-tns.weizmann.ac.il/object/2018cow

My observation from last night - bluish featureless continuum:
sn2018cow.gif
sn2018cow.gif (18.61 KiB) Viewed 14306 times
Guide view (off slit guiding):
guide_sn2018cow.png
guide_sn2018cow.png (141.73 KiB) Viewed 14306 times
The peak where H-alpha should be doesn't seem to be hotpixel: it's 100A away, and when applying the background galaxy's redshift (4241 +/- 39 km/s), I can measure 6561.2A as its barycenter. So that may be from the galaxy.
The "W" shape (absorptions barycenters: 4912A, 4967A) should be also something real (SNR good enough in the green-blue), but none matching by any atel reports.
I will be interested in comparing our results and learn more, here is mine:
asdb_sn2018cow_20180623_915.zip
(9.24 KiB) Downloaded 750 times
Peter
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: SN 2018cow

Post by Robin Leadbeater »

Hi Peter,

Very interesting. This is certainly an odd object. (There are now 30 ATels on this !) I would have expect some clear features in the spectrum by now if it was a normal supernova. I ran it through SNID but it did not come up with any matches.

Cheers
Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Peter Somogyi
Posts: 420
Joined: Sun Jul 13, 2014 8:56 am

Re: SN 2018cow

Post by Peter Somogyi »

Thank you for the look, Robin!
ATEL#11776 also reports vanishing features on the next day (2018-06-24 21:22).
It would be nice to access those spectra as fits files, for a comparison.
Also curious how was the result (overlapping observation with mine) with the T60 at Club Mars.

Peter
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: SN 2018cow

Post by Robin Leadbeater »

An update on this strange object. We still do not know what it is. It could be a new type of supernova or a tidal disruption event
https://www.skyandtelescope.com/uncateg ... stronomers
(Thanks to David Swan on the BAA forum for the link)

Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Post Reply