Related papers: Extraordinary supernova iPTF14hls: An attempt at i…

In recent years, many Type IIn supernovae have been found to share striking similarities with the peculiar SN 2009ip, whose true nature is still under debate. Here, we present 10 years of observations of SN 2011fh, an interacting transient…

We present very early, high-cadence photometric observations of the nearby Type Ia SN 2017cbv. The light curve is unique in that it has a blue bump during the first five days of observations in the U, B, and g bands, which is clearly…

We present the discovery, photometric and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with tau_d=5 days, and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at…

Searching for the presence of circumstellar material is currently the only direct way to discriminate between the different types of possible progenitor systems for Type Ia supernovae. We have therefore looked for narrow H-alpha in a…

Supernova explosions are among the most energetic phenomena in the known universe. There are suggestions that cosmic rays up to EeV energies might be accelerated in the young supernova shell on time scales of a few weeks to years, which…

We report photometry of 1RXS J232953.9+062814, a recently discovered dwarf nova with a remarkably short 64.2-minute orbital period. In quiescence, the star's light curve is that of a double sinusoid, arising from the "ellipsoidal"…

We present new pre-maximum and late-time optical photometry of the Type Ia/IIn supernova 2002ic. These observations are combined with the published V-band magnitudes of Hamuy et al. (2003) and the VLT spectrophotometry of Wang et al. (2004)…

SN 2023ixf is one of the brightest Core Collapse Supernovae of the 21st century and offers a rare opportunity to investigate the late stage of a Supernova through nebular phase spectroscopy. We present four nebular phase spectra from day…

PTF11kx was a Type Ia supernova (SN Ia) that showed time-variable absorption features, including saturated Ca II H&K lines that weakened and eventually went into emission. The strength of the emission component of H{\alpha} increased,…

We present 1500 cycles of hydrogen shell flashes on a 1.38 M_sun white dwarf (WD) for a mass accretion rate of 1.6 x 10^{-7} M_sun yr^{-1}, the mass ejection of which is calculated consistently with the optically thick winds. This model…

A Chandra observation of the Large Magellanic Cloud supernova remnant DEM L241 reveals an interior unresolved source which is probably an accretion-powered binary. The optical counterpart is an O5III(f) star making this a High-Mass X-ray…

An extensive dataset for SN 2003hv that covers the flux evolution from maximum light to day +786 is presented. The data are combined with published nebular-phase infrared spectra, and the observations are compared to model light curves and…

Stellar-mass and supermassive black holes abound in the Universe, whereas intermediate-mass black holes (IMBHs) of ~10^2-10^5 solar masses in between are largely missing observationally, with few cases found only. Here we report the…

A search for recoiling supermassive black hole candidates recently yielded the best candidate thus far, SDSS J092712.65+294344.0 reported by Komossa et al. Here we propose the alternative hypothesis that this object is a supermassive black…

The Type IIn supernova SN 2010jl was relatively nearby and luminous, allowing detailed studies of the near-infrared (NIR) emission. We present 1 - 2.4 micron spectroscopy over the age range of 36 - 565 days from the earliest detection of…

A possibility is explored to account for the light curve and the low expansion velocity of the supernova SN~2011ht, a member of group of three objects showing signatures of both IIn and IIP supernovae. It is argued that the radiated energy…

We present late-time optical spectroscopy taken with the Large Binocular Telescope's Multi-Object Double Spectrograph, an improved ASAS-SN pre-discovery non-detection, and late-time SWIFT observations of the nearby ($d=193$ Mpc, $z=0.0436$)…

We present and analyse spectra of the Type IIn supernova 1994W obtained between 18 and 202 days after explosion. During the first 100 days the line profiles are composed of three major components: (i) narrow P Cygni lines with absorption…

Aims. We study the optical spectroscopic properties of Type Ia Supernova (SN Ia) 2004dt, focusing our attention on the early epochs. Methods. Observation triggered soon after the SN 2004dt discovery allowed us to obtain a spectrophotometric…

Abell 14 is a poorly studied object despite being considered a born again planetary nebula. We performed a detailed study of its 3D morphology and ionization structure using the SHAPE and MOCASSIN codes. We found that Abell 14 is a highly…