Spectroscopic classification of SN 2018bwp as a type Ia supernova a few weeks after peak brightness
ATel #11671; Angel R. Lopez-Sanchez (AAO/Macquarie U.), Lluis Galbany (U. Pittsburgh), Yago Ascasibar (UAM), Kristin Fiegert (AAO), Timothy Barnes, Casey Cunningham, Tony Cristiano, Sarah Dean, Robert Edwards, Nicholas East, Karen Franks, Julie Hams, Robert Ian Higgins, Jennifer Hogan, Rusel Last, Mark Longmuir, Andrew McRae, Neil McElhinney, Rosie Miller, Chris Murphy, Christopher Daniel Andrew Quarrell, Gianna O'Donnell, Michael Rochler, Hayden Roberts, Lyn Robinson, Stephan Soule, Natalie J. Spillman, Paul Shelmerdine, Robert Vassie, Michael Vickers, Jennifer A Westwood (Citizen scientists, Zooniverse), Rebecca J. Smethurst (U. Nottingham), Chris Lintott (U. Oxford), Anais Moller, Brad Tucker, Patrick Armstrong, Charles Bray, Seo-Won Chang, Chris Onken, Ryan Ridden-Harper, Georgie Taylor (ANU), Ashley Ruiter (UNSW Canberra), Brian Cox (U. Manchester), Julia Zemiro (Australian Broadcasting Corporation)
on 24 May 2018; 02:48 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Lluis Galbany (lluisgalbany@gmail.com)
Subjects: Optical, Supernovae
We report the spectroscopic classification of SN 2018bwp (RA=13:25:54.77, DEC=-37:14:12.05) in the galaxy 2MASX J13255427-3714139 . The candidate was discovered by the SkyMapper Transient (SMT) survey (Scalzo et al. 2017, PASA, 34:30) on UT 2018-05-04 09:50 UT at ~19.1 mag in the r-band. SMT utilizes the 268-Mpix camera on the SkyMapper 1.3-m telescope at Siding Spring Observatory near Coonabarabran, NSW, Australia (Keller et al., 2007, PASA, 24, 1). The object was photometrically discovered by citizen scientists as part of the Zooniverse Supernova Sighting Project.
Observations were performed on the 3.9m Anglo-Australian Telescope at Siding Spring Observatory on 2018-05-23 13:46 UT, using KOALA+AAOmega and grisms 580V+385R (3700-5700A and 6100-9300A). Classification was done with SNID (Blondin & Tonry, 2007, ApJ, 666, 1024), and the spectrum is available at the IAU Transient Name Server (see https://wis-tns.weizmann.ac.il/object/2018bwp). The spectrum shows typical broad features characteristic of type Ia supernovae (SNe Ia) past-maximum light. SNID gives a relible fits to all its main spectral features with spectra of normal SNe Ia at ~3 weeks after peak brightness placed at redshift consistent with that of the host galaxy (0.065). We measure a Si II 6355 velocity of -8,700 km/s.
Survey Name | IAU Name | RA (J2000) | Dec (J2000) | Disc. Date | Source | Disc Mag | z | Type | Phase | Notes
SMT18as | SN2018bwp | 13:25:54.77 | -37:14:12.05 | 20180504 | SkyMapper | 19.1r | 0.065 | Ia | +3 weeks | (1,2,3)
(1) Best SNID fit to SN2001N at +20 days and SN2003ic at +22 days. Redshift from host galaxy emission lines (Ha, Hb, [O III] 5007).
(2) Identified as a Supernova Candidate through a project run by the Zooniverse as part of the ABC Stargazing Live show (http://supernovasighting.org).
(3) Was identified by Zooniverse volunteers Timothy Barnes, Casey Cunningham, Tony Cristiano, Sarah Dean, Robert Edwards, Nicholas East, Karen Franks, Julie Hams, Robert Ian Higgins, Jennifer Hogan, Rusel Last, Mark Longmuir, Andrew McRae, Neil McElhinney, Rosie Miller, Chris Murphy, Christopher Daniel Andrew Quarrell, Gianna O'Donnell, Michael Rochler, Hayden Roberts, Lyn Robinson, Stephan Soule, Natalie J. Spillman, Paul Shelmerdine, Robert Vassie, Michael Vickers, and Jennifer A Westwood.
