TNS Classification Report No. 20496 [ 2025TNSCR.836....1C ]
Date Received (UTC): 2025-02-28 11:19:25 Sender: Panos Charalampopoulos
Group: None
Panos Charalampopoulos report/s a classification of object: TDE 2025chm
Type: TDERedshift: 0.101
Remarks: We report the classification of AT2025chm as a Tidal Disruption Event (TDE) based on an optical spectrum obtained with the Nordic Optical Telescope on 2025-02-27 (i.e., MJD 60733.91). The transient appears coincident with the host nucleus. At a redshift of 0.101, we tentatively identify CaII H&K and Hbeta absorption but we note that the redshift might be down to ~ 0.085. We detect broad Halpha, and a blend of broad Hbeta and HeII 4686. Comparison with a library of supernovae spectra using NGSF (Next Generation SuperFit; AstroNote 2022-191, Howell et al. 2005 2005ApJ...634.1190H), suggests AT2025chm is an around peak TDE (see attached images). We note that there is significant MW extinction (Av=0.10) which would make the g-r constant colour evolution to be around -0.35. At that redshift, and correcting for the MW extinction, the current absolute r-band magnitude is Mr ~ -19.4.
The following Classification spectrum was provided:
Obsdate: 2025-02-27 21:54:07
Instrument: ALFOSC
Telescope: Nordic Optical Telescope
Details of the object and its spectra can be viewed here: https://www.wis-tns.org/object/2025chm
Date Received (UTC): 2025-02-28 11:19:25 Sender: Panos Charalampopoulos
Group: None
Panos Charalampopoulos report/s a classification of object: TDE 2025chm
Type: TDERedshift: 0.101
Remarks: We report the classification of AT2025chm as a Tidal Disruption Event (TDE) based on an optical spectrum obtained with the Nordic Optical Telescope on 2025-02-27 (i.e., MJD 60733.91). The transient appears coincident with the host nucleus. At a redshift of 0.101, we tentatively identify CaII H&K and Hbeta absorption but we note that the redshift might be down to ~ 0.085. We detect broad Halpha, and a blend of broad Hbeta and HeII 4686. Comparison with a library of supernovae spectra using NGSF (Next Generation SuperFit; AstroNote 2022-191, Howell et al. 2005 2005ApJ...634.1190H), suggests AT2025chm is an around peak TDE (see attached images). We note that there is significant MW extinction (Av=0.10) which would make the g-r constant colour evolution to be around -0.35. At that redshift, and correcting for the MW extinction, the current absolute r-band magnitude is Mr ~ -19.4.
The following Classification spectrum was provided:
Obsdate: 2025-02-27 21:54:07
Instrument: ALFOSC
Telescope: Nordic Optical Telescope
Details of the object and its spectra can be viewed here: https://www.wis-tns.org/object/2025chm