SALT spectroscopic classification of ASASSN-18sy as a dwarf nova
ATel #11993; D. A. H. Buckley (SAAO), M. Gromadzki (Warsaw), Subo Dong, Subhash Bose (KIAA-PKU)
on 28 Aug 2018; 14:41 UT
Credential Certification: Subo Dong (dongsubo@pku.edu.cn)
Subjects: Optical, Cataclysmic Variable
ASASSN-18sy (RA: 14:45:37.51 Dec: -34:07:12.2; IAU name: AT 2018fge) was discovered by the All Sky Automated Survey for SuperNovae (ASAS-SN, Shappee et al. 2014) on UT 2018-08-19 23:45:36 at g = 15.5 mag. As part of the SALT Large Science Program on transients, it was observed with the Southern African Large Telescope (SALT) using the Robert Stobie Spectrograph on UT 2018-08-23.77 UT (JD 2458354.2701) employing the PG300 lines/mm grating. A 600s exposure spectrum, covering 3400 - 9000 Angstroms at a resolution of ~18 Angstroms with a 1.5 arcsec slit, was obtained in clear conditions. The spectrum shows a very blue continuum with H I Balmer absorption lines, with H-alpha filled in but not obvious emission reversal. H-beta has an EW of 6.6 Angstrom and FWHM of 41.3 Angstrom. We interpret the spectrum to be that of a Dwarf Nova in outburst.
The spectrum is made available with TNS.
