ASASSN-18gn: new transient (13.7 mag) in Apus

Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Mon, 04/02/2018 - 17:49

ASASSN-18gn (UG:)
https://www.aavso.org/vsx/index.php?view=detail.top&oid=612062

RA 14h49m11.41s, DEC -73°33'17.7" (J2000.0)
"Bright CV candidate, could also be an X-ray nova in outburst, matches to GAIA G=19.6, g>17.8 on 2018-03-29.20, g=14.0 on 2018-03-30.28, V=13.8 on 2018-03-31.39, V=13.7 on 2018-04-02.29"
http://www.astronomy.ohio-state.edu/~assassin/transients.html

Also in USNO-A2.0 and B1.0, matches to GALEX J144911.1-733317.

ASASSN-18gn 20180329.20 <178g ASN
ASASSN-18gn 20180330.28 140g ASN
ASASSN-18gn 20180331.39 138V ASN
ASASSN-18gn 20180402.29 137V ASN

Spectroscopy and time-resolved photometry during the current outburst are strongly recommended.

Clear skies,
Patrick

Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Likely SU UMa-type dwarf nova

ASASSN-18gn (UGSU:)
https://www.aavso.org/vsx/index.php?view=detail.top&oid=612062

Prior to discovery on 2018 March 31, four outbursts were recorded by the ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K):
2014 July 24, mag 13.1 V (superoutburst?);
2015 March 8, 13.7 V (normal outburst?);
2016 August 20, 13.3 V (superoutburst?);
2017 July 23, 13.6 V (normal outburst?).
https://asas-sn.osu.edu/light_curves/756ab4f5-8a94-485a-ae4c-00f78f5702…

The current outburst looks again like a superoutburst. Time-resolved photometry is urgently required.

Clear skies,
Patrick