We report spectroscopic observations of AT2020bio with the SPRAT instrument on the Liverpool Telescope (Steele, Iain A., Smith, Robert J., Rees, Paul C. et al. 2004). The transient, associated with NGC 5371 (z=0.009), was discovered by Koichi Itagaki on MJD 58877.77 (2020-01-29 18:27:37) at 16.7 magnitude (clear filter). ATLAS (Tonry et al. 2018, PASP, 13, 064505) detected the transient on MJD 58878.53 at an orange band magnitude of m_o = 16.44 +/- 0.02 (M_o ~ -16), following non-detections on MJD 58874.67 and 58876.67.
The spectrum (4000-8000 A) is largely featureless with a blue continuum, lacking flash ionization features. A shallow, broad feature is possibly detected between 5500-6000. Assuming this feature is HeI 5876, the deduced velocity is ~11,000 km/sec. The ATLAS photometry indicates a rapid rise of ~3 mag in a span of roughly 2 days. The observations indicate that AT2020bio is a young core collapse supernova.
Catalog | Name | Reported RA | Reported DEC | Reported Obj-Type | Reported Redshift | Host Name | Host Redshift | Remarks | TNS RA | TNS DEC | TNS Obj-Type | TNS Redshift |
---|---|---|---|---|---|---|---|---|---|---|---|---|
TNS | 2020bio | 13:55:37.685 | +40:28:39.02 | 0.009 | NGC 5371 | 13:55:37.687 | +40:28:39.15 | SN | 0.009 |