ZTF24abfaake/AT 2024ule was first detected by ZTF at 12:09:13 on 2024-09-02 UT and reported as a transient to TNS at 18:24:27 on 2024-09-03 UT. It was selected as a potential tidal disruption event (TDE) both by the Neural Engine for Discovering Luminous Events (NEEDLE) classifier (Sheng et al. 2024) in astronote 2024-289 and as part of ZTF’s regular scanning for TDE-like light curves. The source rose to peak ~19 days after first detection with a peak magnitude near g = 18.5 and r=19 before slowly fading while maintaining a blue (g-r~-0.4) color.
A classification spectrum was taken on 2024-10-25 UT using the Kast spectrograph on the 3 m Shane telescope at Lick Observatory (range 3500-10500 Angs) under bright sky background conditions. The spectrum exhibits a blue continuum with a broad emission line centered near 7300 Angs , which we identify as H-alpha at redshift z=0.112. A second spectrum (range 3850-7000 Angs) was taken under better conditions with the Goodman High Throughput Spectrograph on the 4m SOAR telescope on 2024-10-28 UT (PI: Andreoni). The SOAR spectrum shows a blue continuum with broad (~7000 km/s) H and He II emission lines with weak Ca II absorption lines from the host implying a redshift of z=0.112.
Based on the lightcurve evolution, blue photometric colors, and broad emission lines of H and He II, we classify ZTF24abfaake/AT 2024ule as a TDE-H+He.
Follow up with the Neil Gehrels Swift Observatory has been requested.
| 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 | 2024ule [ZTF24abfaake] | 08:14:27.141 | +09:00:01.47 | TDE-H-He | 08:14:27.141 | +09:00:01.47 |