We obtained a spectrum of the rapidly evolving transient AT2026cha/ZTF26aaffxis (Astronotes #2026-29, #2026-30, #2026-31) with VLT/X-shooter (Program 115.28HS.001, PI Chrimes) approximately 8 days post-discovery on 2026-02-13 (MJD start time 61084.079). 2x1200s exposures were taken with a 1x11 arsec slit and no binning. Calibration data were taken the same night, including observations of a standard star (GD 71). Data reduction and flux calibration were performed with Pypeit (Prochaska 2020).
AT2026cha shows spectral evolution consistent with the peculiar Ic-BL classification of Astronote #2026-31. The Gelato classification tool (Harutyunyan et al. 2008) finds that SN2003jd and SN1997ef (both type Ic-BL) are the best matches at a similar epoch of ~5-10 days.
We thank the ESO staff for their help in promptly obtaining these observations.
| 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 | 2026cha [ZTF26aaffxis] | 08:32:33.106 | -26:28:37.90 | SN Ic-BL | 0.0393 | 08:32:33.106 | -26:28:37.90 | SN IIb | 0.0393 |
Comments