OGLE-2015-NOVA-01: A possible classical nova?
ATel #7179; P. Mroz, A. Udalski (Warsaw University Observatory, Poland), on behalf of the OGLE team
on 5 Mar 2015; 21:14 UT
Credential Certification: Przemek Mroz (firstname.lastname@example.org)
Subjects: Optical, Cataclysmic Variable, Nova, Transient
We report the discovery of a possible classical nova (OGLE-2015-NOVA-01) located toward the Galactic bulge in data from the Optical Gravitational Lensing Experiment (OGLE) sky survey. The transient was detected by the Early Warning System (EWS), which has been designed for the detection of microlensing events. However, the light curve does not resemble that of a microlensing event.
OGLE-2015-NOVA-01 is located (RA,DEC) = (17:48:12.82, -32:35:13.4) J2000.0 or (l,b) = (357.16574, -2.36870), 2 arcsec from a bright constant star (I~16.3 mag). The transient started brightening around 2015 February 26, reaching approximately I=14 mag on 2015 March 3.30265 UT. In the latest frame, taken on 2015 March 5.37919 UT, it faded by 0.4 mag.
A possible progenitor is faint, I=20.2 mag. It was not detected in V-band frames, meaning it has V>21.2 mag. This star has been monitored by the OGLE since 2010. No previous outbursts were detected. There is no periodic signal in quiescence.
The star may be heavily reddened. According to the VVV extinction map (Gonzalez et al., 2012, A&A 543, 13), the color excess E(J-Ks) in 2 arcmin region around the nova is 1.03 mag.
Neither infrared nor X-ray counterpart to our object was found in IRSA and HEASARC archives.
Follow-up observations are encouraged. OGLE will continue the photometric monitoring of this object.
Finding charts and light curves are available here.