Discovery certificate for object 2018xc
TNS Astronomical Transient Report No. 17017 [ 2018TNSTR.247....1B ]

Date Received (UTC): 2018-02-20 17:20:23
Sender: Prof. Krzysztof Stanek
Source Group: ASAS-SN

D. Bersier, K. Z. Stanek, for the ASAS-SN team report/s the discovery of a new astronomical transient.

IAU Designation: AT 2018xc
Discoverer internal name: ASASSN-18di
Coordinates (J2000): RA = 09:58:30.511 (149.62713) DEC = +14:55:39.00 (14.9275)
Discovery date: 2018-02-20 02:21:07 (JD=2458169.5979977)


Remarks: Very bright new source without a Vizier, SDSS or PS1 match, so likely a high-amplitude CV, but could also be a SN

Photometry

Discovery (first detection):
Discovery date: 2018-02-20 02:21:07
Flux: 14.3 VegaMag
Filter: V-Johnson
Instrument: Cassius
Telescope: ASASSN-Cassius

Last non-detection:
Last non-detection date: 2018-02-17 03:21:36
Limiting flux: 18.7 ABMag
Filter: g-Sloan
Instrument: Paczynski
Telescope: ASASSN-Paczynski


Details of the new object can be viewed here: https://wis-tns.weizmann.ac.il/object/2018xc