680 datasets found

Active galactic nuclei (AGN) can vary significantly in their rest-frame optical/UV continuum emission, and with strong associated changes in broad line emission, on much shorter...

We examine and quantify how hybrid (e.g., UV+IR) star formation rate (SFR) estimators and the A_FUV_-{beta} relation depend on inclination for disk-dominated galaxies using...

Are WO-type Wolf-Rayet (WR) stars in the final stage of massive star evolution before core-collapse? Although WC- and WO-type WRs have very similar spectra, WOs show a much...

We examine the UV/X-ray properties of 1378 quasars in order to link empirical correlations to theoretical models of the physical mechanisms dominating quasars as a function of...

We report on a long-term optical monitoring of the neutron star X-ray binary Centaurus X-4 performed during the last 13.5yr. This source has been in quiescence since its...

We present a well-designed sample of more than 1000 type 1 quasars at 3.5<z<5 and derive UV quasar luminosity functions (QLFs) in this redshift range. These quasars were...

Seeing pristine material from the donor star in a type Ia supernova (SN Ia) explosion can reveal the nature of the binary system. In this paper, we present photometric and...

We present observations of SN 2021csp, the second example of a newly identified type of supernova (SN) hallmarked by strong, narrow, P Cygni carbon features at early times (Type...

We combine 126 new galaxy-OVI absorber pairs from the CGM^2^ survey with 123 pairs drawn from the literature to examine the simultaneous dependence of the column density of OVI...

Using ultraviolet (UV) light curves, we constrain the circumstellar environments of 1080 Type Ia supernovae (SNe Ia) within z<0.5 from archival Galaxy Evolution Explorer...

Dual supermassive black holes (SMBHs) at ~kiloparsec scales are the progenitor population of SMBH mergers and play an important role in understanding the pairing and dynamical...

We compose a 265-sight-line Milky Way CIV line-shape sample using the Hubble Space Telescope/Cosmic Origins Spectrograph archive, which is complementary to the existing SiIV...

In this Letter we report a discovery of a prominent flash of a peculiar overluminous Type Ia supernova, SN 2020hvf, in about 5hr of the supernova explosion by the first...

We characterize the local (2kpc sized) environments of Type Ia, II, and Ib/c supernovae (SNe) that have recently occurred in nearby (d<~50Mpc) galaxies. Using ultraviolet...

We present a study of candidate galaxy-absorber pairs for 43 low-redshift QSO sightlines (0.06<z<0.85) observed with the Hubble Space Telescope/Cosmic Origins Spectrograph...

We report the results of near-infrared spectroscopic observations of 37 quasars in the redshift range 6.3<z<=7.64, including 32 quasars at z>6.5, forming the largest...

We present new redshift measurements for 19 candidate ultra-diffuse galaxies (UDGs) from the Systematically Measuring Ultra-Diffuse Galaxies (SMUDGes) survey after conducting a...

We present a new investigation of the intergalactic medium (IGM) near the end of reionization using "dark gaps" in the Ly{alpha} forest. Using spectra of 55 QSOs at...

We present the results of the Cosmic Origins Spectrograph-Intragroup Medium (COS-IGrM) Survey that used the COS on the Hubble Space Telescope to observe a sample of 18 UV bright...

We present the 30 minutes cadence Kepler/K2 light curve of the Type Ia supernova (SN Ia) SN 2018agk, covering approximately one week before explosion, the full rise phase, and...