A new candidate for central tidal disruption event in SDSS J014124 + 010306 with broad Mg ii line at z = 1.06

Abstract

ABSTRACT In the letter, a new candidate for central tidal disruption event (TDE) is reported in SDSS J014124 + 010306 (= SDSS J0141) with broad Mg ii line at redshift $\mathit{ z}$ = 1.06. Based on long-term photometric ugriz-band variabilities from SDSS Stripe82 Data base and PHOTOOBJALL data base, a central TDE is preferred with a 1.3 M⊙ main-sequence star tidally disrupted by central black hole (BH) of (14 ± 2) × 106 M⊙ in SDSS J0141. Moreover, CAR process has been applied to confirm that the probability is only about 0.4 per cent that the long-term variabilities in SDSS J0141 are not related to TDE but from intrinsic active galactic nucleus (AGN) activities. Meanwhile, based on the apparent broad Mg ii emission lines, virial BH mass can be estimated as 245 × 106 M⊙, 18 times larger than the TDE model determined BH mass, providing further clues to support a central TDE in SDSS J0141, similar to the case in the TDE candidate SDSS J0159 with virial BH mass two magnitudes larger than M-sigma relation expected BH mass. Among the reported optical TDE candidates, SDSS J0141 is the candidate at the highest redshift. The results in the letter indicate it should be common to detect TDE candidates in high redshift galaxies with broad Mg ii lines.