Related papers: A very faint core-collapse supernova in M85

We report on the X-ray properties of the new transient Swift J0840.7$-$3516, discovered with Swift/BAT in 2020 February, using extensive data of Swift, MAXI, NICER, and NuSTAR. The source flux increased for $\sim 10^3$ s after the…

Supernovae (SNe) are thought to arise from two different physical processes. The cores of massive, short-lived stars undergo gravitational core collapse and typically eject a few solar masses during their explosion. These are thought to…

We present photometric and spectroscopic data of the peculiar SN 2005la, an object which shows an optical light curve with some luminosity fluctuations and spectra with comparably strong narrow hydrogen and helium lines, probably of…

We present adaptive optics imaging of the core collapse supernova (SN) 2009md, which we use together with archival \emph{Hubble Space Telescope} data to identify a coincident progenitor candidate. We find the progenitor to have an absolute…

The extragalactic background light at far-infrared wavelengths originates from optically-faint, dusty, star-forming galaxies in the universe with star-formation rates at the level of a few hundred solar masses per year. Due to the…

We present medium-resolution spectroscopy and multicolor photometry for the optical transient PSN J09093496+3307204 (SN 2015bh) in the galaxy NGC 2770, which has transferred into the supernova phase. The observations were carried out…

We present a search for an electromagnetic counterpart of the gravitational wave source GW151226. Using the Pan-STARRS1 telescope we mapped out 290 square degrees in the optical i_ps filter starting 11.5hr after the LIGO information release…

A binary system (G3425) consisting of a massive unseen component and a red giant star on a nearly circular orbit was recently discovered. The formation of such a system is puzzling because orbital stability generally breaks down due to the…

The continuing difficulty of achieving a reliable explosion in simulations of core-collapse supernovae, especially for more massive stars, has led to speculation concerning the observable transients that might be produced if such a…

We report the discovery of an object near M87 in the Virgo Cluster with an extraordinary blueshift of -1025 km/s, offset from the systemic velocity by >2300 km/s. Evaluation of photometric and spectroscopic data provides strong evidence…

Supernova (SN) 2006gy was a hydrogen-rich core-collapse SN that remains one of the most luminous optical supernovae ever observed. The total energy budget (> 2 x 10^51 erg radiated in the optical alone) poses many challenges for standard SN…

The Galactic center has some of the highest stellar densities in the Galaxy and a range of interstellar scattering properties that may aid in the detection of new radio-selected transient events. Here we describe a search for radio…

We report on the serendipitous discovery of a star-forming galaxy at redshift z=0.116 with morphological features that indicate an ongoing merger. This object exhibits two clearly separated components with significantly different colors,…

We report on a quasi-periodic variation at $\sim1$ Hz during a fast X-ray outburst of a high-mass X-ray binary MAXI J0709$-$159 / LY CMa observed by the Neutron-star interior composition explorer (NICER). The new X-ray transient MAXI…

Using observations from an extensive monitoring campaign with the Hubble Space Telescope we present the detection of an intermediate-time flux excess which is redder in color relative to the afterglow of GRB 011121, currently distinguished…

The radio-loud active galactic nucleus in M 87 hosts a powerful jet fueled by a super-massive black hole in its center. A bright feature 80 pc away from the M 87 core has been reported to show superluminal motions, and possibly to be…

We report on the discovery of the near-IR transient of the long-duration gamma-ray burst GRB 030528 and its underlying host galaxy. The near-IR transient was first observed in JHKs with SofI at the 3.6m ESO-NTT 16hrs after the burst and…

We have made thirteen positive identifications of near-ultraviolet (NUV) transient sources in the giant elliptical galaxy M87 using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). We give a…

KIC 5773205 is the least luminous eclipsing M dwarf found in the Villanova catalog of eclipsing binaries detected by the {\it Kepler} mission. We processed and analyzed the three available quarters of mission data for this star and…

Nova Sco 2008 (=V1309 Sco) is an example of a V838 Mon type eruption rather than a typical classical nova. This enigmatic object was recently shown to have resulted from the merger of two stars in a contact binary. It is the first stellar…