Support ATel At Patreon

[ Previous | Next | ADS ]

SCAT Classification of PS18kh as a potential TDE

ATel #11473; Michael A. Tucker, Mark Huber, Benjamin J. Shappee (IfA, Hawai'i), Jose L. Prieto (Diego Portales; MAS), T. W.-S. Holoien (Carnegie Observatories), Subo Dong, S. Bose, Ping Chen (KIAA-PKU), E. Falco, M. Calkins (Harvard CfA), K. C. Chambers, H. Flewelling, T. Lowe. E. Magnier, A. Schultz, C. Waters, R. J. Wainscoat, M. Wilman (IfA, Hawai'i), K. W. Smith, S. J. Smartt, D. R. Young (QUB), D. E. Wright (University of Minnesota)
on 24 Mar 2018; 06:58 UT
Credential Certification: Benjamin Shappee (shappee@hawaii.edu)

Subjects: Optical, Transient, Tidal Disruption Event

PS18kh (AT 2018zr) was discovered by Pan-STARRS1 on UT 2018-03-02 at i = 18.63 mag. The position of the transient was consistent with the center of the host galaxy (SDSS J075654.53+341543.6) at an unknown redshift.

As part of the newly formed Spectral Classification of Astronomical Transients (SCAT) survey utilizing the SuperNova Integral Field Spectrograph (SNIFS) on the University of Hawaii 88-inch telescope, we obtained optical spectra (range 3300-9700 angstroms) on 2018-03-07T07:33 under cloudy conditions (exposure time 1220s) and 2018-03-18T10:17 under nearly-photometric conditions (exposure time 2020s).

We then obtained follow-up low-resolution optical spectra on 2018-03-20.T02:09 with WFCCD mounted on the du Pont 2.5m at Las Campanas Observatory (range 3600-9600 angstroms, exposure time 3300s) and on 2018-03-20.T04:04 with FAST mounted on the F. L. Whipple Observatory 1.5-m telescope (3500-7300 angstroms, exposure time 1800s).

These four spectra all show very blue continua with nearly featureless spectra. There are potentially very broad Balmer series lines present at a very rough redshift of z~0.075. The long time scale, coincidence with the center of the host galaxy, blue spectra, and potential broad Balmer lines are all consistent with a tidal disruption event.

Follow-up observations, especially high S/N spectroscopy, are strongly encouraged.

Information on all objects discovered by the Pan-STARRS Survey for Transients is available at http://star.pst.qub.ac.uk/ps1threepi/ (see Chambers et al. arXiv:1612.05560, panstarrs.ifa.hawaii.edu; Huber et al. ATel #7153).