Related papers: Redshift of the Einstein Ring in MG1549+305

Millimeter observations of the galactic source of relativistic ejections GRS 1915+105 (Mirabel & Rodriguez 1994) are consistent with this source being at a kinematic distance D = 12.5 +/- 1.5 kpc from the Sun, behind the core of a molecular…

We discuss the ratio of the angular diameter distances from the source to the lens, $D_{ds}$, and to the observer at present, $D_{s}$, for various dark energy models. It is well known that the difference of $D_s$s between the models is…

Inspiralling compact binaries as standard sirens will soon become an invaluable tool for cosmology when advanced interferometric gravitational-wave detectors begin their observations in the coming years. However, a degeneracy in the…

We present a near-infrared (NIR) spectrum of WISE J1042+1641, an extremely red dust-obscured galaxy (DOG), which has been observed with the LIRIS on the 4.2m William Hershel Telescope. This object was selected as a hyper-luminous DOG…

We show that the Einstein ring radius and transverse speed of a lens projected on the source plane, $\hat{r}_{\rm e}$ and $\hat{v}$, can be determined from the light curve of a binary-source event, followed by the spectroscopic…

The determination of the redshift of extragalactic gamma ray sources is of fundamental importance for the interpretation of their emission models and extragalactic population studies, AGN classification schemes, and to study the interaction…

We present the discovery and a detailed multi-wavelength study of a strongly-lensed luminous infrared galaxy at z=0.816. Unlike most known lensed galaxies discovered at optical or near-infrared wavelengths this lensed source is red, r-Ks =…

We present the results of a comprehensive Spitzer survey of 70 radio galaxies across 1<z<5.2. Using IRAC, IRS and MIPS imaging we determine the rest-frame AGN contribution to the stellar emission peak at 1.6um. The stellar luminosities are…

We report the discovery of four very bright, strongly-lensed galaxies found via systematic searches for arcs in Sloan Digital Sky Survey Data Release 5 and 6. These were followed-up with spectroscopy and imaging data from the Astrophysical…

We present the results of our multi-wavelength (X-ray to radio) follow-up campaign of the Einstein Probe transient EP240408a. The initial 10 s trigger displayed bright soft X-ray (0.5-4 keV) radiation with peak luminosity $L_\textrm{X}…

(abridged) We present Gemini integral-field unit (IFU) spectroscopy and Hubble Space Telescope (HST) F435W- and F814W-band images of a new four-image gravitational lens, SDSSJ140228.22+632133.3, obtained as part of an HST Snapshot program…

Black hole binaries with extreme ($\gtrsim 10^4:1$) or intermediate ($\sim 10^2-10^4:1$) mass ratios are among the most interesting gravitational wave sources that are expected to be detected by the proposed Laser Interferometer Space…

We report the discovery, using NICMOS on the Hubble Space Telescope, of an arcsecond-diameter Einstein ring in the gravitational lens system B1938+666. The lensing galaxy is also detected, and is most likely an early-type. Modelling of the…

We present the first case of strong gravitational lensing by a QSO : SDSS J0013+1523, at z = 0.120. The discovery is the result of a systematic search for emission lines redshifted behind QSOs, among 22298 spectra of the SDSS data release…

[Abridged] We discovered in the Herschel Reference Survey an extremely bright IR source with $S_{500}$~120mJy (Red Virgo 4 - RV4). Based on IRAM/EMIR and IRAM/NOEMA detections of the CO(5-4), CO(4-3), and [CI] lines, RV4 is located at…

The gravitational lens SDSS J1148+1930, also known as the Cosmic Horseshoe, is one of the biggest and of the most detailed Einstein rings ever observed. We use the forward reconstruction method implemented in the lens fitting code Lensed to…

We report redshifts in two gravitational lens systems, MG0414+0534 and MG0751+2716. The lens galaxy in MG0414+0534 lies at z_l=0.9584+/-0.0002. The luminosity and extreme red color of the lens are then typical of a passively evolving,…

We present the optical spectra of four newly discovered gravitational lenses from the Cosmic Lens All-Sky Survey (CLASS). These observations were carried out using the Low Resolution Imaging Spectrograph on the W. M. Keck-I Telescope as…

We present a study of HerS-3, a dusty star-forming galaxy at zspec = 3.0607, which is gravitationally amplified into an Einstein cross with a fifth image of the background galaxy seen at the center of the cross. Detailed 1-mm spectroscopy…

PKS1830-211 is an unusually radio-loud gravitationally lensed quasar. In the radio, the system appears as two compact, dominant features surrounded by relatively extended radio emission which forms an Einstein Ring. As the line of sight to…