NOT classifications: supernovae 2018ekt and 2018exb

ATel #11955; M. Stritzinger (Aarhus), Subo Dong (KIAA-PKU), J. Fynbo (NBI, DAWN), K. Alizai (DTU-Space), C. Gomez (DAWN), F. Haidari, M. Malloy, P. S. Rehal, D. Slumstrup (Aarhus), S. B. Svendsen (DTU-Space)
on 15 Aug 2018; 11:36 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Subo Dong (dongsubo@pku.edu.cn)

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On behalf of the Danish Summer School in Observational Astrophysics, currently being held at the Nordic Optical Telescope (NOT), we report the spectroscopic classifications of SN 2018ekt and SN 2018exb. The candidates were discovered by the Pan-STARRS Survey for Transients (PSST; Huber et al., ATel #7153) and ATLAS (Tonry et al. 2011; ATel #8680).

Observations were performed with the 2.56 m Nordic Optical Telescope equipped with ALFOSC (range 350-950 nm; resolution 1.6 nm FWHM).

 
Survey Name    | IAU Name   | Discovery (UT) | Discovery mag | Observation (UT) | Redshift | Type | Phase   | Notes 
PS18bby        | SN2018ekt  | 2018-07-08.4   | 20.9          | 2018-08-15.1     | 0.015    | Ia   | +14d    | (1) 
ATLAS18tnd     | SN2018exb  | 2018-08-11.4   | 17.7          | 2018-08-15.1     | 0.047    | Ia   | -7d     | (2) 

(1) Type Ia supernova around two weeks or more past maximum light. SNID (Blondin and Tonry 2007, ApJ, 666, 1024) determines good template fits for the redshift z=0.015. (2) SNID indicates decent matches with spectra of SN 2006gr and SN 2007F obtained around a week before maximum. Host red-shift of z=0.047 comes from The 6dF Galaxy Survey Data Release 3 (Jones et al. 2009, MNRAS, 399, 683). We note that SNID suggests a host redshift of z=0.022.