[vsnet-outburst 16972] ASASSN-14ca (ATEL)

[Taichi Kato]

   The existence of a past outburst would suggest
a dwarf nova with a large outburst amplitude.
Observations are encouraged.

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ATEL #6211							     ATEL #6211

Title:	ASAS-SN Discovery of a Bright Transient Source near CGCG477-027
Author:	A. B. Davis, B. J. Shappee, K. Z. Stanek, T. W.-S. Holoien,
		C. S. Kochanek, J. Jencson, U. Basu, J. F. Beacom (Ohio State), J.
		L. Prieto (Princeton), D. Szczygiel, G. Pojmanski (Warsaw University
		Observatory), J. Brimacombe (Coral Towers Observatory), D. Bersier
		(LJMU)
Queries:	davis.4811 at osu.edu
Posted:	9 Jun 2014; 03:01 UT
Subjects:Optical, Transient

During the ongoing All Sky Automated Survey for SuperNovae (ASAS-SN or

"Assassin"), using data from the quadruple 14-cm "Brutus" telescope in

Haleakala, Hawaii, we discovered a new transient source. 

Object       RA (J2000)     DEC (J2000)      Disc. UT Date   Disc. V mag

ASASSN-14ca  23:53:13.23   +27:42:01.64      2014-06-7.60       15.5  

ASASSN-14ca was discovered in images obtained on 2014 UT June 7.60 at V~15.5
mag. We also detect the object in images obtained on June 3.59, June 5.59,
June 8.56, and June 8.61. We do not detect this object in images taken
on 2014 UT June 2.57 and before. This <a href=http://www.astronomy.ohio-state.edu/~assassin/followup/ASASSN-14ca.png>figure</a>
shows the ASAS-SN reference image (top left), archival SDSS g-band image
(top right), the ASAS-SN June 3.59 image (bottom left), and the ASAS-SN
June 8.61 image (bottom right). The green circle has a radius of 5" at
the position of the transient derived from the ASAS-SN image. 

A cross-check of the ASAS-SN position in Vizier reveals that the nearest
source is a faint (g~20.58) and red (g-r=0.66) star roughly 0.24" away
from our position of the transient. The line-of-sight Galactic extinction
at this position is A_V=0.118 (Schlafly & Finkbeiner 2011), so nearby sources
are not likely to be significantly reddened. There are CRTS data at the
position of the object which show a previous outburst on 2005 UT July 5.37
of similar magnitude and duration of least 6 days (data do not well constrain
the beginning nor the end of the flare). 

ASASSN-14ca appears to be a long-lived (> 5 days) transient associated
with a red source.  Follow up observations, especially spectroscopic, are
encouraged. 

We thank LCOGT and its staff for their continued support of ASAS-SN. For

more information about the ASAS-SN project, see the <a href=http://www.astronomy.ohio-state.edu/~assassin/index.shtml>ASAS-SN

Homepage</a> and the list of all <a href=http://www.astronomy.ohio-state.edu/~assassin/transients.html>ASAS-SN

transients</a>.