[vsnet-alert 17892] ASASSN-14ho (ATEL)

[Taichi Kato]

ASASSN-14ho (ATEL)

   It was a bright CV in outburst!

ASASSN-14ho 	--- 	------- 	6:30:27.34 	-65:29:50.2 	2014-09-21.35 	11.41 	SDSS 	DSS 	VIZIER 	------- 	very bright outburst from reddish, quiescent star, V=15.4 on 2014-09-06.37, V=12.2 on 2014-09-09.36, V=11.0 on 2014-09-11.36, V=11.1 on 2014-09-12.36, V=11.4 on 2014-09-17.35, V=11.5 on 2014-09-21.34, V=11.5 on 2014-09-22.34, only weak variability in CRTS

ASASSN-14ho 20140906.37 154V ASN
ASASSN-14ho 20140909.36 122V ASN
ASASSN-14ho 20140911.37 10.92V ASN
ASASSN-14ho 20140912.36 111V ASN
ASASSN-14ho 20140917.35 114V ASN
ASASSN-14ho 20140921.34 115V ASN
ASASSN-14ho 20140922.34 115V ASN
ASASSN-14ho 20141002.33 11.88V ASN
ASASSN-14ho 20141011.28 14.94V ASN
ASASSN-14ho 20141021.29 127V ASN

(see also vsnet-alert 17760, 17761)

===

ATEL #6619                                                           ATEL #6619

Title:  The outburst of the bright CV ASASSN-14ho
Author: J. L. Prieto (Diego Portales; MAS), L. Sturch (BU), B. Madore
                (Carnegie Observatories), A. B. Davis, K. Z. Stanek, G. Simonian,
                T. W.-S. Holoien, C. S. Kochanek, U. Basu, J. F. Beacom (Ohio State),
                B. J. Shappee (Hubble Fellow, Carnegie Observatories), D. Bersier
                (LJMU), J. Brimacombe (Coral Towers Observatory), D. Szczygiel, G.
                Pojmanski (Warsaw University Observatory) 
Queries:        jose.prietok at mail.udp.cl
Posted: 24 Oct 2014; 19:59 UT
Subjects:Optical, Cataclysmic Variable, Transient

We report optical imaging and spectroscopy of the bright transient ASASSN-14ho
(RA = 06:30:27.3, DEC = -65:29:50.2, see <a href="http://www.astronomy.ohio-state.edu/~assas
sin/transients.html">ASAS-SN
transients</a>). We obtained a low resolution optical spectrum on UT 2014
Sep 25.4 with the WFCCD spectrograph mounted on the du Pont 2.5m telescope
at LCO. The spectrum shows H-alpha and He II 4686 lines in emission, as
well as other Balmer lines in absorption with emission-line cores (see
<a href="http://www.astronomy.ohio-state.edu/~assassin/followup/asassn14ho_spec.png">this
figure</a>). The H-alpha has a red asymmetry and can be well fit with two
Gaussians centered at -200 and +200 km/s. This is consistent with a Galactic
CV in outburst.   

The ASAS-SN light curve of ASASSN-14ho shows an outburst starting on UT
2014 Sep. 9.36, when it raised from V=15.4 on Sep. 6.37 to V=12.2 mag.
The source then brightened to peak V=10.92 on Sep. 11.37 and declined slowly
to V=11.88 on Oct. 2.33, when it started to decline faster to V=14.94 (~0.5
mag brighter than its quiescent magnitude) on Oct. 11.28. After this it
showed two further re-brightenings and it had V=12.7 on Oct. 21.29. The
full light curve can be found <a href="http://www.astronomy.ohio-state.edu/~assassin/followup/asassn14ho_lc.png">here</a>.

ASASSN-14ho has a measured proper motion of pmRA = -16.9 +/- 1.7 mas and
pmDEC = 60.5 +/- 1.7 mas in the SPM4 catalog (Girard et al. 2011), suggesting
that this a nearby star. The pre-outburst source shows little variability
in CRTS (Drake et al. 2009), has B-V=0.5 mag with an SED peaking at 2MASS
J-band (see <a href="http://cdsxmatch.u-strasbg.fr/gadgets/ifr?url=http://cdsxmatch.u-strasbg.fr/widgets/SED_plotter.xml&SED_plot_object=06:30:27.3%20%20-65:29:50.2&SED_plot_radius=2">
Vizier SED</a>), and it is likely detected in ROSAT (1RXS J063029.4-653003). Follow-up observations are encouraged.