SN 2013ab : A normal type IIP supernova in NGC 5669
  We present densely-sampled ultraviolet/optical photometric and low-resolution
optical spectroscopic observations of the type IIP supernova 2013ab in the
nearby ($\sim$24 Mpc) galaxy NGC 5669, from 2 to 190d after explosion.
Continuous photometric observations, with the cadence of typically a day to one
week, were acquired with the 1-2m class telescopes in the LCOGT network, ARIES
telescopes in India and various other telescopes around the globe. The light
curve and spectra suggest that the SN is a normal type IIP event with a plateau
duration of $ \sim80 $ days with mid plateau absolute visual magnitude of
-16.7, although with a steeper decline during the plateau (0.92 mag 100 d$
^{-1} $ in $ V $ band) relative to other archetypal SNe of similar brightness.
The velocity profile of SN 2013ab shows striking resemblance with those of SNe
1999em and 2012aw. Following the Rabinak & Waxman (2011) prescription, the
initial temperature evolution of the SN emission allows us to estimate the
progenitor radius to be $ \sim $ 800 R$_{\odot}$, indicating that the SN
originated from a red supergiant star. The distance to the SN host galaxy is
estimated to be 24.3 Mpc from expanding photosphere method (EPM). From our
observations, we estimate that 0.064 M$_{\odot}$ of $^{56}$Ni was synthesized
in the explosion. General relativistic, radiation hydrodynamical modeling of
the SN infers an explosion energy of $ 0.35\times10^{51} $ erg, a progenitor
mass (at the time of explosion) of $ \sim9 $ M$_{\odot}$ and an initial radius
of $ \sim600 $ R$_{\odot}$.
