Magellan optical spectral identification of Astronomical Transients
ATel #14278; M. DÃaz, N. Morrell, M. Phillips (Las Campanas Observatory, Chile) and M. Stritzinger (Aarhus University, Denmark).
on 18 Dec 2020; 16:45 UT
Credential Certification: Nidia Morrell (nmorrell@lco.cl)
Subjects: Optical, Star, Supernovae
On November 30 UT we obtained optical spectroscopy (range 425-940 nm, 0.5 nm resolution) with the Las Campanas 6.5 m Magellan I Baade telescope (+IMACS) of the transients listed below, which were selected from the Transient Name Server.
2020aavs: Galactic star. Blue continuum with broad Balmer emission lines exhibiting central absorption. A much fainter He II 468.6 nm emission feature is also discernible. We note that the spectrum is noisy due to the bright background from the Moon.
2020aayy: Early B-type star with faint H-alpha emission; radial velocity consistent with the Large Magellanic Cloud.
2020abbq: Carbon star, very similar to SS Vir (e.g.
https://www.cloudynights.com/topic/634371-some-spectra-of-ss-vir-a-mira-variable-carbon-star/).
2020abbr: Galactic star displaying broad Balmer absorption lines with central emission.
He II 468.6 nm is seen in emission as well.
2020abcr: Normal type Ia supernova at a redshift around 0.05, according to the Supernova Identification Tool (SNID, Blondin and Tonry 2007, ApJ, 666, 1024). SNID finds many good matches with normal type Ia supernovae between zero and four days from maximum light.
2020abdr exhibits an almost featureless, blue continuum with an emission feature around 470 nm. This object might be a young core collapse supernova, although we are not able to be more conclusive. A faint emission feature is present at 678.2 nm, which if assumed to be H-alpha originated in the host, would imply a redshift of 0.033.
