TY  - JOUR
KW  - Black hole physics
KW  -  gravitational waves
KW  -  galaxies: nuclei
KW  -  ultraviolet: general
KW  -  transients: tidal disruption events
N1  - This work is licensed under a Creative Commons Attribution 4.0 International License. The images
or other third-party material in this article are included in the Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this
license, visit http://creativecommons.org/licenses/by/4.0/
IS  - 2
EP  - 1710
TI  - Swift/UVOT discovery of Swift J221951?484240: a UV luminous ambiguous nuclear transient
AV  - public
JF  - Monthly Notices of the Royal Astronomical Society
PB  - Oxford University Press (OUP)
A1  - Oates, SR
A1  - Kuin, NPM
A1  - Nicholl, M
A1  - Marshall, F
A1  - Ridley, E
A1  - Boutsia, K
A1  - Breeveld, AA
A1  - Buckley, DAH
A1  - Cenko, SB
A1  - De Pasquale, M
A1  - Edwards, PG
A1  - Gromadzki, M
A1  - Gupta, R
A1  - Laha, S
A1  - Morrell, N
A1  - Orio, M
A1  - Pandey, SB
A1  - Page, MJ
A1  - Page, KL
A1  - Parsotan, T
A1  - Rau, A
A1  - Schady, P
A1  - Stevens, J
A1  - Brown, PJ
A1  - Evans, PA
A1  - Gronwall, C
A1  - Kennea, JA
A1  - Klingler, NJ
A1  - Siegel, MH
A1  - Tohuvavohu, A
A1  - Ambrosi, E
A1  - Barthelmy, SD
A1  - Beardmore, AP
A1  - Bernardini, MG
A1  - Bonnerot, C
A1  - Campana, S
A1  - Caputo, R
A1  - Ciroi, S
A1  - Cusumano, G
A1  - Aì, AD
A1  - Avanzo, PD
A1  - Elia, VD
A1  - Giommi, P
A1  - Hartmann, DH
A1  - Krimm, HA
A1  - Malesani, DB
A1  - Melandri, A
A1  - Nousek, JA
A1  - Brien, PTO
A1  - Osborne, JP
A1  - Pagani, C
A1  - Palmer, DM
A1  - Perri, M
A1  - Racusin, JL
A1  - Sakamoto, T
A1  - Sbarufatti, B
A1  - Schlieder, JE
A1  - Tagliaferri, G
A1  - Troja, E
A1  - Xu, D
VL  - 530
SP  - 1688
N2  - We report the discovery of Swift J221951?484240 (hereafter: J221951), a luminous slow-evolving blue transient that was detected by the Neil Gehrels Swift Observatory Ultraviolet/Optical Telescope (Swift/UVOT) during the follow-up of gravitational wave alert S190930t, to which it is unrelated. Swift/UVOT photometry shows the UV spectral energy distribution of the transient to be well modelled by a slowly shrinking blackbody with an approximately constant temperature of T ? 2.5 × 104 K. At a redshift z = 0.5205, J221951 had a peak absolute magnitude of Mu,AB = ?23 mag, peak bolometric luminosity Lmax = 1.1 × 1045 erg s?1 and a total radiated energy of E > 2.6 × 1052 erg. The archival Wide-field Infrared Survey Explorer IR photometry shows a slow rise prior to a peak near the discovery date. Spectroscopic UV observations display broad absorption lines in N V and O VI, pointing towards an outflow at coronal temperatures. The lack of emission in the higher H ? lines, N I and other neutral lines is consistent with a viewing angle close to the plane of the accretion or debris disc. The origin of J221951 cannot be determined with certainty but has properties consistent with a tidal disruption event and the turn-on of an active galactic nucleus.
UR  - http://dx.doi.org/10.1093/mnras/stae795
ID  - discovery10192060
Y1  - 2024/05/01/
ER  -