Are 3XMM J2150 and EP240222a really off-nuclear tidal disruption events?

0 Assigned ID: 6888 ----- Attempting Submission 1 (Thu Apr 10 23:57:45 GMT 2025) ----- ----- Attempting Submission 2 (Tue Apr 15 19:11:11 GMT 2025) ----- 0 ----- Attempting Submission 1 (Wed Aug 06 11:30:51 GMT 2025) ----- HST Phase II Proposal 18054 successfully submitted. Receipt: # 18054-1 ----- Attempting Submission 2 (Thu Aug 14 10:19:31 GMT 2025) ----- ----- Attempting Submission 3 (Thu Oct 02 00:59:13 GMT 2025) ----- Are 3XMM J2150 and EP240222a really off-nuclear tidal disruption events? Galaxy merger simulations predict a substantial population of off-nuclear massive black holes (MBHs). Tidal disruption events (TDEs) occurring around these wandering MBHs provide a rare window into studying these otherwise dormant black holes. Recently, AT 2024tvd was confirmed as the first optically selected off-nuclear TDE. Two other X-ray selected events have also been put forward as off-nuclear TDE candidates: 3XMM J2150 and EP240222a. However, their separation from the purported host galaxy is large (13 and 35 kpc, respectively). It is not clear that the two MBHs are even linked to the larger "host galaxy". Therefore, we request deep HST imaging of these 2 off-nuclear TDE candidates to 1) detect signatures of faint satellite galaxies that might host these TDEs, ii) detect UV emission from the TDe accretion disks. These deep and high spatial resolution images will help answer whether these are indeed off-nuclear MBHs like AT 2024tvd. We will obtain imaging with WFC3/UVIS of 2 off-nuclear tidal disruption event candidates: Visit 1) 3XMMJ215: F225W (1 orbit) Visit 2) EP240222A: F225W (1 orbit) + F625W (1 orbit) This team has performed extensive observational and theoretical work in the area of stellar and black hole astrophysics, especially TDEs, AGN physics, and supernovae. PI Dr. Kishore Patra is an expert observer who has significant experience in time-domain astronomy. He has authored several papers on supernovae, TDEs and related nuclear transient events. He will lead the data analysis and publication of results. He is a PI of active HST and JWST proposals. CoIs Prof. Ryan Foley is an observer and previous PI/CoI of multiple HST and JWST programs. He is a coauthor on several TDE papers. Supermassive Black Holes and Active Galaxies Galaxies 6 false false false false false false SUPPORTED GALAXY ACCRETION DISK ELLIPTICAL TIDAL TAIL J2000 J2000 GALAXY ACCRETION DISK ELLIPTICAL TIDAL TAIL J2000 J2000 WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F625W POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1

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