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We present optical photometric and spectroscopic analysis of a Type Iax supernova (SN) 2020rea situated at the brighter luminosity end of Type Iax supernovae (SNe). The light curve decline rate of SN~2020rea is $\Delta$m$_{15}$(g) = 1.31$\pm$0.08 mag which is similar to SNe 2012Z and 2005hk. Modelling the pseudo bolometric light curve with a radiation diffusion model yields a mass of $^{56}$Ni of 0.13$\pm$0.01 M$_{\odot}$ and an ejecta mass of 0.77$^{+0.11}_{-0.21}$ M$_{\odot}$. Spectral features of SN~2020rea during the photospheric phase show good resemblance with SN 2012Z. TARDIS modelling of the early spectra of SN~2020rea reveals a dominance of Iron Group Elements (IGEs). The photospheric velocity of the Si {\sc II} line around maximum for SN~2020rea is $\sim$ 6500 km s$^{-1}$ which is less than the measured velocity of the Fe {\sc II} line and indicates significant mixing. The observed physical properties of SN~2020rea match with the predictions of pure deflagration model of a Chandrasekhar mass C-O white dwarf. The metallicity of the host galaxy around the SN region is 12+log(O/H) = 8.56$\pm$0.18 dex which is similar to that of SN 2012Z., Comment: 11 pages, 12 figures, 4 tables, accepted for publication in Monthly Notices of the Royal Astronomical Society (MNRAS)

Interacting supernovae (SNe) IIn and Ibn show narrow emission lines and have always been a mysterious and unsolved genre in SNe physics. We present a comprehensive analysis of the temporal and spectroscopic behaviour of a group of interacting SNe~IIn and Ibn. We choose SNe~2012ab, 2020cui, 2020rc and 2019uo as representative members of these SN sub-types to probe the nature of explosion. Our study reveals that SNe~IIn are heterogeneous, bright depicting multi-staged temporal evolution while SNe~Ibn are moreover homogeneous, comparatively fainter than SNe~IIn and short lived, but limited in sample to firmly constrain the homogeneity. The spectroscopic features display a great diversity in H$\alpha$ and He profiles for both SNe~IIn and Ibn. The representative SN~Ibn also show flash ionisation signatures of CIII and NIII. Modelling of H$\alpha$ reveals that SNe~IIn have in general an asymmetric CSM which interacts with SN ejecta resulting in diversity in H$\alpha$ profiles., Comment: 9 pages, 8 figures, Accepted for Special Issue of Journal of Astrophysics and Astronomy, 2022, Astrophysical jets and observational facilities: National perspective, 05 -09 April 2021, ARIES Nainital

We present the photometric and spectroscopic analysis of three Type II SNe: 2014cx, 2014cy and 2015cz. SN 2014cx is a conventional Type IIP with a shallow slope (0.2 mag/50d) and an atypical short plateau ($\sim$86 d). SNe 2014cy and 2015cz show relatively large decline rates (0.88 and 1.64 mag/50d, respectively) at early times before settling to the plateau phase, unlike the canonical Type IIP/L SN light curves. All of them are normal luminosity SN II with an absolute magnitude at mid-plateau of M$_{V,14cx}^{50}$=$-$16.6$\pm$0.4$\,\rm{mag}$, M$_{V,14cy}^{50}$=$-$16.5$\,\pm\,$0.2$\,\rm{mag}$ and M$_{V,15cz}^{50}$=$-$17.4$\,\pm\,$0.3$\,\rm{mag}$. A relatively broad range of $^{56}$Ni masses is ejected in these explosions (0.027-0.070 M$_\odot$). The spectra show the classical evolution of Type II SNe, dominated by a blue continuum with broad H lines at early phases and narrower metal lines with P Cygni profiles during the plateau. High-velocity H I features are identified in the plateau spectra of SN 2014cx at 11600 km s$^{-1}$, possibly a sign of ejecta-circumstellar interaction. The spectra of SN 2014cy exhibit strong absorption profile of H I similar to normal luminosity events whereas strong metal lines akin to sub-luminous SNe. The analytical modelling of the bolometric light curve of the three events yields similar radii for the three objects within errors (478, 507 and 608 R$_\odot$ for SNe 2014cx, 2014cy and 2015cz, respectively) and a range of ejecta masses (15.0, 22.2 and 18.7 M$_\odot$ for SNe 2014cx, 2014cy and 2015cz), and a modest range of explosion energies (3.3 - 6.0 foe where 1 foe = 10$^{51}$ erg)., Comment: 20 pages, 23 Figures, 3 figures in appendix, accepted for publication in MNRAS

We present the photometric and spectroscopic studies of a Type Ib SN 2015ap and a Type Ic SN 2016P. SN 2015ap is one of the bright (M$_{V}$ = $-$18.04 mag) Type Ib while SN 2016P lies at an average value among the Type Ic SNe (M$_{V}$ = $-$17.53 mag). Bolometric light curve modelling of SNe 2015ap and 2016P indicates that both the SNe are powered by $^{56}$Ni + magnetar model with $^{56}$Ni masses of 0.01 M$_{\odot}$ and 0.002 M$_{\odot}$, ejecta masses of 3.75 M$_{\odot}$ and 4.66 M$_{\odot}$, spin period P$_{0}$ of 25.8 ms and 36.5 ms and magnetic field B$_{p}$ of 28.39 $\times$ 10$^{14}$ Gauss and 35.3 $\times$ 10$^{14}$ Gauss respectively. The early spectra of SN 2015ap shows prominent lines of He with a "W" feature due to Fe complexes while other lines of Mg II, Na I and Si II are present in both SNe 2015ap and 2016P. Nebular phase [O I] profile indicates an asymmetric profile in SN 2015ap. The [O I]/[Ca II] ratio and nebular spectral modelling of SN 2015ap hints towards a progenitor mass between 12 $-$ 20 M$_{\odot}$., 22 pages, 21 Figures, Accepted for publication in MNRAS, The replaced version includes high resolution corner plots

We present DELIGHT, or Deep Learning Identification of Galaxy Hosts of Transients, a new algorithm designed to automatically and in real-time identify the host galaxies of extragalactic transients. The proposed algorithm receives as input compact, multi-resolution images centered at the position of a transient candidate and outputs two-dimensional offset vectors that connect the transient with the center of its predicted host. The multi-resolution input consists of a set of images with the same number of pixels, but with progressively larger pixel sizes and fields of view. A sample of \nSample galaxies visually identified by the ALeRCE broker team was used to train a convolutional neural network regression model. We show that this method is able to correctly identify both relatively large ($10\arcsec < r < 60\arcsec$) and small ($r \le 10\arcsec$) apparent size host galaxies using much less information (32 kB) than with a large, single-resolution image (920 kB). The proposed method has fewer catastrophic errors in recovering the position and is more complete and has less contamination ($< 0.86\%$) recovering the cross-matched redshift than other state-of-the-art methods. The more efficient representation provided by multi-resolution input images could allow for the identification of transient host galaxies in real-time, if adopted in alert streams from new generation of large etendue telescopes such as the Vera C. Rubin Observatory., Submitted to The Astronomical Journal on Aug 5th, 2022. Comments and suggestions are welcome

We present deep Chandra X-ray observations of two nearby Type Ia supernovae, SN 2017cbv and SN 2020nlb, which reveal no X-ray emission down to a luminosity $L_X$$\lesssim$5.3$\times$10$^{37}$ and $\lesssim$5.4$\times$10$^{37}$ erg s$^{-1}$ (0.3--10 keV), respectively, at $\sim$16--18 days after the explosion. With these limits, we constrain the pre-explosion mass-loss rate of the progenitor system to be $\dot{M}$$, Comment: 19 pages, 6 figures, ApJ Accepted

We present the detailed optical evolution of a Type Ib SN 2015dj in NGC 7371, using data spanning up to ∼170 days after discovery. SN 2015dj shares similarity in light-curve shape with SN 2007gr and peaks at M V = -17.37 0.02 mag. Analytical modeling of the quasi bolometric light curve yields 0.06 0.01 M o˙ of 56Ni, ejecta mass M o˙, and kinetic energy erg. The spectral features show a fast evolution and resemble those of spherically symmetric ejecta. The analysis of nebular phase spectral lines indicates a progenitor mass between 13-20 M o˙, suggesting a binary scenario., K.M. acknowledges the support from the Department of Science and Technology (DST), Government of India, and Indo-US Science and Technology Forum (IUSSTF) for the WISTEMM fellowship and the Department of Physics, UC Davis, where part of this work was carried out. K.M. also acknowledges BRICS grant DST/IMRCD/BRICS/Pilotcall/ProFCheap/2017(G) for the present work. Research by S.V. is supported by NSF grant AST-1813176. NUTS is supported in part by the Instrument Center for Danish Astrophysics (IDA). E.C., N.E.R., L.T., S. B., and M.T. are partially supported by PRIN-INAF 2016 with the project “Toward the SKA and CTA era: discovery, localization, and physics of transient sources” (P.I. M. Giroletti).

We present multiband photometry and spectroscopy of SN 2018cuf, a Type IIP (“P” for plateau) supernova (SN) discovered by the Distance Less Than 40 Mpc Survey within 24 hr of explosion. SN 2018cuf appears to be a typical SN IIP, with an absolute V-band magnitude of −16.73 ± 0.32 at maximum and a decline rate of 0.21 ± 0.05 mag/50 days during the plateau phase. The distance of the object was constrained to be 41.8 ± 5.7 Mpc by using the expanding photosphere method. We used spectroscopic and photometric observations from the first year after the explosion to constrain the progenitor of SN 2018cuf using both hydrodynamic light-curve modeling and late-time spectroscopic modeling. The progenitor of SN 2018cuf was most likely a red supergiant of about 14.5 M⊙ that produced 0.04 ± 0.01 M⊙ ⁵⁶Ni during the explosion. We also found ∼0.07 M⊙ of circumstellar material (CSM) around the progenitor is needed to fit the early light curves, where the CSM may originate from presupernova outbursts. During the plateau phase, high-velocity features at ∼11,000 km s⁻¹ were detected in both the optical and near-infrared spectra, supporting the possibility that the ejecta were interacting with some CSM. A very shallow slope during the postplateau phase was also observed, and it is likely due to a low degree of nickel mixing or the relatively high nickel mass in the SN., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata

We present a high-cadence short term photometric and spectroscopic monitoring campaign of a type Ibn SN 2019wep, which is one of the rare SN Ibn after SNe 2010al and 2019uo to display signatures of flash ionization (\ion{He}{2}, \ion{C}{3}, \ion{N}{3}). We compare the decline rates and rise time of SN 2019wep with other SNe Ibn and fast transients. The post-peak decline in all bands (0.1 mag d$^{-1}$) are consistent with SNe Ibn but less than the fast transients. On the other hand, the $\Delta$m$_{15}$ values are slightly lower than the average values for SNe Ibn but consistent with the fast transients. The rise time is typically shorter than SNe Ibn but longer than fast transients. SN 2019wep lies at the fainter end of SNe Ibn but possesses an average luminosity amongst the fast transients sample. The peculiar color evolution places it between SNe Ib and the most extreme SNe Ibn. The bolometric light curve modelling shows resemblance with SN 2019uo with ejecta masses consistent with SNe Ib. SN 2019wep belongs to the "P cygni" sub-class of SNe Ibn and shows faster evolution in line velocities as compared to the "emission" sub-class. The post-maximum spectra show close resemblance with ASASSN-15ed hinting it to be of SN Ib nature. The low \ion{He}{1} CSM velocities and residual H$\alpha$ further justifies it and gives evidence of an intermittent progenitor between WR and LBV star., Comment: 19 pages, 14 figures, 2 Tables, Accepted for publication in ApJ main journal

We present results of the photometric (from 3 to 509 days past explosion) and spectroscopic (up to 230 days past explosion) monitoring campaign of the He-rich Type IIb supernova (SN) 2015as. The {\it (B-V)} colour evolution of SN 2015as closely resemble those of SN 2008ax, suggesting that SN 2015as belongs to the SN IIb subgroup that does not show the early, short-duration photometric peak. The light curve of SN 2015as reaches the $B$-band maximum about 22 days after the explosion, at an absolute magnitude of -16.82 $\pm$ 0.18 mag. At $\sim$ 75 days after the explosion, its spectrum transitions from that of a SN II to a SN Ib. P~Cygni features due to He I lines appear at around 30 days after explosion, indicating that the progenitor of SN 2015as was partially stripped. For SN~2015as, we estimate a $^{56}$Ni mass of $\sim$ 0.08 M$_{\odot}$ and ejecta mass of 1.1--2.2 M$_{\odot}$, which are similar to the values inferred for SN 2008ax. The quasi bolometric analytical light curve modelling suggests that the progenitor of SN 2015as has a modest mass ($\sim$ 0.1 M$_{\odot}$), a nearly-compact ($\sim$ 0.05$\times$10$^{13}$ cm) H envelope on top of a dense, compact ($\sim$ 2$\times$10$^{11}$ cm) and a more massive ($\sim$ 1.2 M$_{\odot}$) He core. The analysis of the nebular phase spectra indicates that $\sim$ 0.44 M$_{\odot}$ of O is ejected in the explosion. The intensity ratio of the [Ca II]/[O I] nebular lines favours either a main sequence progenitor mass of $\sim$ 15 M$_{\odot}$ or a Wolf Rayet star of 20 M$_{\odot}$., 23 pages, 18 figures, 10 tables, Accepted for publication in MNRAS, 16 February, 2018

This paper presents data and analysis of SN 2010kd, a low-redshift ($z = 0.101$) H-deficient superluminous supernova (SLSN), based on ultraviolet/optical photometry and optical spectroscopy spanning between $-$28 and +194 days relative to $\mathit{B}$ band maximum light. The $\mathit{B}$ band light curve comparison of SN 2010kd with a subset of well-studied SLSNe I at comparable redshifts indicates that it is a slow-decaying PTF12dam like SLSN. Analytical light-curve modeling using the $\mathtt{Minim}$ code suggests that the bolometric light curve of SN 2010kd favors circumstellar matter interaction for the powering mechanism. $\mathtt{SYNAPPS}$ modeling of the early-phase spectra does not identify broad H or He lines, whereas the photospheric-phase spectra are dominated by O I, O II, C II, C IV and Si II, particularly, presence of both low and high-velocity components of O II and Si II lines. The nebular-phase spectra of SN 2010kd are dominated by O I and Ca II emission lines similar to those seen in other SLSNe I. The line velocities in SN 2010kd exhibit flatter evolution curves similar to SN 2015bn but with comparatively higher values. SN 2010kd shows a higher single-zone local thermodynamic equilibrium temperature in comparison to PTF12dam and SN 2015bn, and it has an upper O I ejected mass limit of $\sim 10~M_\odot$. The host of SN 2010kd is a dwarf galaxy with a high star-formation rate ($\sim 0.18 \pm 0.04~M_\odot$ yr$^{-1}$) and extreme emission lines., 26 pages, 16 figures, Accepted in ApJ, updated to match the accepted version

We present an extensive (∼1200 d) photometric and spectroscopic monitoring of the Type IIn supernova (SN) 2012ab. After a rapid initial rise leading to a bright maximum (MR = −19.39 mag), the light curves show a plateau lasting about 2 months followed by a steep decline up to about 100 d. Only in the U band, the decline is constant in the same interval. At later phases, the light curves remain flatter than the 56Co decline, suggesting the increasing contribution of the interaction between SN ejecta with circumstellar material (CSM). Although heavily contaminated by emission lines of the host galaxy, the early spectral sequence (until 32 d) shows persistent narrow emissions, indicative of slow unshocked CSM, and the emergence of broad Balmer lines of hydrogen with P-Cygni profiles over a blue continuum, arising from a fast expanding SN ejecta. From about 2 months to ∼1200 d, the P-Cygni profiles are overcome by intermediate width emissions [full width at half-maximum (FWHM) ∼6000 km s−1], produced in the shocked region due to interaction. On the red wing, a red bump appears after 76 d, likely a signature of the onset of interaction of the receding ejecta with the CSM. The presence of fast material both approaching and then receding is suggestive that we are observing the SN along the axis of a jet-like ejection in a cavity devoid of or uninterrupted by CSM in the innermost regions., NER acknowledges support from the Spanish MICINN grant ESP2017-82674-R and FEDER funds. SB, LT, and MT are partially supported by the PRIN-INAF 2016 with the project Towards the SKA and CTA era: discovery, localization, and physics of transient sources (PI: M. Giroletti).

We present photometric and spectroscopic observations of the type Ibn supernova (SN) 2019uo, the second ever SN Ibn with flash ionization (He II, C III, N III) features in its early spectra. SN 2019uo displays a rapid post-peak luminosity decline of 0.1 mag d$^{-1}$ similar to most of the SNe Ibn, but is fainter ($M^V_{max} = -18.30 \pm 0.24$ mag) than a typical SN Ibn and shows a color evolution that places it between SNe Ib and the most extreme SNe Ibn. SN 2019uo shows P-cygni He I features in the early spectra which gradually evolves and becomes emission dominated post peak. It also shows faster evolution in line velocities as compared to most other members of the type Ibn subclass. The bolometric light curve is fairly described by a $^{56}$Ni + circumstellar interaction model., 14 figures, 4 tables, Accepted for publication in ApJ, Corner plots are put in low resolution due to size limitations, please contact authors for original figure

We present photometry, polarimetry and spectroscopy of the Type II supernova ASASSN-16ab/SN 2016B in PGC 037392. The photometric and spectroscopic follow-up commenced about two weeks after shock breakout and continued until nearly six months. The light curve of SN 2016B exhibits intermediate properties between those of Type IIP and IIL. The early decline is steep (1.68 $\pm$ 0.10 mag 100 d$^{-1}$), followed by a shallower plateau phase (0.47 $\pm$ 0.24 mag 100 d$^{-1}$). The optically thick phase lasts for 118 d, similar to Type IIP. The $^{56}$Ni mass estimated from the radioactive tail of the bolometric light curve is 0.082 $\pm$ 0.019 M$_\odot$. High velocity component contributing to the absorption trough of H$\alpha$ and H$\beta$ in the photospheric spectra are identified from the spectral modelling from about 57 - 97 d after the outburst, suggesting a possible SN ejecta and circumstellar material interaction. Such high velocity features are common in the spectra of Type IIL supernovae. By modelling the true bolometric light curve of SN 2016B, we estimated a total ejected mass of $\sim$15 M$_\odot$, kinetic energy of $\sim$1.4 foe and an initial radius of $\sim$400 R$_\odot$., Comment: 16 pages, 4 pages Appendix, 20 figures, 8 tables, Accepted for publication in MNRAS, 01-April-2019

We present the photometry and spectroscopy of SN 2015an, a Type II Supernova (SN) in IC 2367. The recombination phase of the SN lasts up to $\sim$120 d, with a decline rate of 1.24 mag/100d, higher than the typical SNe IIP. The SN exhibits bluer colours than most SNe II, indicating higher ejecta temperatures. The absolute $V$-band magnitude of SN 2015an at 50 d is $-$16.83$\pm$0.04 mag, pretty typical for SNe II. However, the $^{56}$Ni mass yield, estimated from the tail $V$-band light curve to be 0.021$\pm$0.010 M$_\odot$, is comparatively low. The spectral properties of SN 2015an are atypical, with low H$\alpha$ expansion velocity and presence of high velocity component of H$\alpha$ at early phases. Moreover, the continuum exhibits excess blue flux up to $\sim$50 d, which is interpreted as a progenitor metallicity effect. The high velocity feature indicates ejecta-circumstellar material interaction at early phases. The semi-analytical modelling of the bolometric light curve yields a total ejected mass of $\sim$12 M$_\odot$, a pre-supernova radius of $\sim$388~R$_\odot$ and explosion energy of $\sim$1.8 foe., Comment: 15 Pages, 16 Figures, 8 Tables, Accepted for publication in MNRAS, 2019 September 20

MASTER OT J120451.50+265946.6 (M12045), discovered by the MASTER Global Robotic Net, is a Type Ib supernova (SN) that exploded in NGC 4080. We present the {\it BVRI} photometric and spectroscopic observations upto $\sim$250 days since $B_{max}$. At the time of discovery the SN was a few weeks past maximum light and our observations capture the linearly declining light curve phase. M12045 declines faster as compared to SNe 1999dn and 2009jf at comparable epochs. Rigorous spectroscopic monitoring reveals that M12045 is a normal Type Ib SN. The analysis of the nebular phase spectra indicates that $\sim$ 0.90 M$_\odot$ of O is ejected in the explosion. The line ratio of [\ion{O}{I}] and [\ion{Ca}{II}] in the nebular phase supports a massive WR progenitor with main sequence mass of $\sim$ 20 M$_\odot$., Comment: 16 pages, 6 tables, 12 figures, Accepted for publication in MNRAS

We present the discovery and high-cadence follow-up observations of SN 2018ivc, an unusual Type II supernova that exploded in NGC 1068 (D=10.1 Mpc). The light curve of SN 2018ivc declines piecewise-linearly, changing slope frequently, with four clear slope changes in the first 30 days of evolution. This rapidly changing light curve indicates that interaction between the circumstellar material and ejecta plays a significant role in the evolution. Circumstellar interaction is further supported by a strong X-ray detection. The spectra are rapidly evolving and dominated by hydrogen, helium, and calcium emission lines. We identify a rare high-velocity emission-line feature blueshifted at ~7800 km/s (in Ha, Hb, Pb, Pg, HeI, CaII), which is visible from day 18 until at least day 78 and could be evidence of an asymmetric progenitor or explosion. From the overall similarity between SN 2018ivc and SN 1996al, the \Ha{} equivalent width of its parent HII region, and constraints from pre-explosion archival Hubble Space Telescope images, we find that the progenitor of SN 2018ivc could be as massive as 52 Msun but is more likely, Accepted by ApJ. Revised version includes more extensive progenitor analysis

We present optical photometry and spectroscopy from about a week after explosion to $\sim$272 d of an atypical Type IIP supernova, SN 2015ba, which exploded in the edge-on galaxy IC 1029. SN 2015ba is a luminous event with an absolute V-band magnitude of -17.1$\pm$0.2 mag at 50 d since explosion and has a long plateau lasting for $\sim$123 d. The distance to the SN is estimated to be 34.8$\pm$0.7 Mpc using the expanding photosphere and standard candle methods. High-velocity H-Balmer components constant with time are observed in the late-plateau phase spectra of SN 2015ba, which suggests a possible role of circumstellar interaction at these phases. Both hydrodynamical and analytical modelling suggest a massive progenitor of SN 2015ba with a pre-explosion mass of 24-26 M$_\odot$. However, the nebular spectra of SN 2015ba exhibit insignificant levels of oxygen, which is otherwise expected from a massive progenitor. This might be suggestive of the non-monotonical link between O-core masses and the zero-age main-sequence mass of pre-supernova stars and/or uncertainties in the mixing scenario in the ejecta of supernovae., 42 pages, 7 pages Appendix, 20 figures, 10 tables, Accepted for publication in MNRAS, 14-June-2018

We present optical photometric (upto $\sim$410 days since $B$$_{max}$) and spectroscopic (upto $\sim$157 days since $B$$_{max}$) observations of a Type Iax supernova (SN) 2014dt located in M61. SN 2014dt is one of the brightest and closest (D $\sim$ 20 Mpc) discovered Type Iax SN. SN 2014dt best matches the light curve evolution of SN 2005hk and reaches a peak magnitude of $M$$_B$ $\sim$-18.13$\pm$0.04 mag with $\Delta m_{15}$ $\sim$1.35$\pm 0.06$ mag. The early spectra of SN 2014dt are similar to other Type Iax SNe, whereas the nebular spectrum at 157 days is dominated by narrow emission features with less blending as compared to SNe 2008ge and 2012Z. The ejecta velocities are between 5000 to 1000 km sec$^{-1}$ which also confirms the low energy budget of Type Iax SN 2014dt as compared to normal Type Ia SNe. Using the peak bolometric luminosity of SN 2005hk we estimate $^{56}$Ni mass of $\sim$0.14 M$_{\odot}$ and the striking similarity between SN 2014dt and SN 2005hk implies that a comparable amount of $^{56}$Ni would have been synthesized in the explosion of SN 2014dt., Comment: 12 figures, 7 tables, Accepted for publication in MNRAS

We present high-cadence ultraviolet (UV), optical, and near-infrared (NIR) data on the luminous Type II-P supernova SN 2017gmr from hours after discovery through the first 180 days. SN 2017gmr does not show signs of narrow, high-ionization emission lines in the early optical spectra, yet the optical lightcurve evolution suggests that an extra energy source from circumstellar medium (CSM) interaction must be present for at least 2 days after explosion. Modeling of the early lightcurve indicates a ~500R$_{\odot}$ progenitor radius, consistent with a rather compact red supergiant, and late-time luminosities indicate up to 0.130 $\pm$ 0.026 M$_{\odot}$ of $^{56}$Ni are present, if the lightcurve is solely powered by radioactive decay, although the $^{56}$Ni mass may be lower if CSM interaction contributes to the post-plateau luminosity. Prominent multi-peaked emission lines of H$\alpha$ and [O I] emerge after day 154, as a result of either an asymmetric explosion or asymmetries in the CSM. The lack of narrow lines within the first two days of explosion in the likely presence of CSM interaction may be an example of close, dense, asymmetric CSM that is quickly enveloped by the spherical supernova ejecta., Comment: Submitted to ApJ, 25 pages, plus Appendix