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 obse
rvations, 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 $ 0.35times10^{51} $ erg, a progenitor mass (at the time of explosion) of $ sim9 $ M$_{odot}$ and an initial radius of $ sim600 $ R$_{odot}$.
We present $UBVRI$ CCD photometry and optical spectra of the type Ia supernova SN 2003hx which appeared in the galaxy NGC 2076, obtained till $sim$ 146 days after the epoch of $B$ band maximum. The supernova reached at maximum brightness in $B$ band
on JD 245 2893 $pm$ 1.0 with an apparent magnitude of 14.92 $pm$ 0.01 mag which was estimated by making template fits to the light curves. SN 2003hx is an example of a highly reddened supernova with $E(B-V)$ = 0.56 $pm$ 0.23. We estimate $R_v$ = 1.97 $pm$ 0.54 which indicates the small size of dust particles as compared to their galactic counterparts. The luminosity decline rate is $Delta m_{15}(B)$ = 1.17 $pm$ 0.12 mag and the absolute $B$ band magnitude obtained from the luminosity versus decline rate relation (Phillips et al. 1999) is $M^B_{max}$ = -19.20 $pm$ 0.18 mag. The peak bolometric luminosity indicates that $sim$ 0.66 $M_odot$ mass of $^{56}$ Ni was ejected by the supernova. The spectral evolution indicates the supernova to be a normal type Ia event.
We present X-ray, broad band optical and low frequency radio observations of the bright type IIP supernova SN 2004et. The cxo observed the supernova at three epochs, and the optical coverage spans a period of $sim$ 470 days since explosion. The X-ray
emission softens with time, and we characterise the X-ray luminosity evolution as $Lx propto t^{-0.4}$. We use the observed X-ray luminosity to estimate a mass-loss rate for the progenitor star of $sim ee{2}{-6} M_odot mathrm{yr}^{-1}$. The optical light curve shows a pronounced plateau lasting for about 110 days. Temporal evolution of photospheric radius and color temperature during the plateau phase is determined by making black body fits. We estimate the ejected mass of $^{56}$Ni to be 0.06 $pm$ 0.03 M$_odot$. Using the expressions of Litvinova & Nad{e}zhin (1985) we estimate an explosion energy of (0.98 $pm$ 0.25) $times 10^{51}$ erg. We also present a single epoch radio observation of SN 2004et. We compare this with the predictions of the model proposed by Chevalier et al. (2006). These multi-wavelength studies suggest a main sequence progenitor mass of $sim$ 20 M$_odot$ for SN 2004et.
