Photometric evolution of the M31 nova PTF12ahb
ATel #3920; K. Hornoch (Astronomical Institute, Ondrejov, Czech Republic)
on 13 Feb 2012; 05:24 UT
Credential Certification: Allen W. Shafter (aws@nova.sdsu.edu)
Subjects: Optical, Nova, Transient
Additional photometric observations of the unusual nova PTF12ahb (ATEL #3905
and #3912) were obtained with the 0.65-m telescope at Ondrejov:
Date UT Mag Band
2012 02 05.744 19.4 +/- 0.2 R
2012 02 08.720 19.2 +/- 0.1 R
2012 02 08.732 18.9 +/- 0.25 I
2012 02 10.725 19.0 +/- 0.15 R
2012 02 12.721 18.35 +/- 0.10 R
Combined with the two measurements from ATEL #
3912, the current photometry
shows that after reaching an initial maximum (faint for a typical nova in M31)
followed by fast drop of the brightness, the nova started brightening again.
This opens possibility that the object could belong to group of slow novae,
which would be consistent with its unusually low expansion velocity
(FWHM ~ 600 km/s, ATEL #
3912).
The color (R-I) ~ 0.3 does not support the possibility that the object
could be significantly extinguished. In the light of recent photometry,
it also seems unlikely that this is a typical member of the fast and faint
group of novae.
I thank Petr Zasche for sharing part of his observing time which made
it possible to obtain measurements on the night of Feb. 8.
