TNS Classification Report No. 23418 [ 2026TNSCR1413....1D ]

Date Received (UTC): 2026-04-03 17:59:37
Sender: Kaustav Kashyap Das
Group: ZTF

Kaustav K. Das (Caltech), K-Ryan Hinds (Caltech), Daniel A. Perley (LJMU), Jesper Sollerman, Avinash Singh (Stockholm University) on behalf of the ZTF collaboration. report/s a classification of object: SN 2025xtq

Type: SN Ia-CSM
Redshift: 0.054

Remarks: The spectrum reveals strong H-alpha emission with a velocity of ~7500 km s⁻¹, along with prominent Ca II NIR emission. The H-alpha emission is consistent with z = 0.054 and indicates ongoing interaction with H-rich circumstellar material (CSM). The spectral properties resemble Ia-CSM events such as SN 2013dn, but with a significantly longer-lived and flat light curve. Spectrum obtained with SEDM on 2025-09-25 matches to Type Ia SN.

The following Classification spectrum was provided:

Obsdate: 2026-04-02 00:00:00
Instrument: NGPS
Telescope: Palomar 5.1m Hale

Details of the object and its spectra can be viewed here: https://www.wis-tns.org/object/2025xtq