Related papers: The Apparently Normal Galaxy Hosts for Two Luminou…
The ~800 optically unseen (R>25.5) 24mum-selected sources in the complete Spitzer First Look Survey sample (Fadda et al. 2006) with F[24mum]>0.35 mJy are found to be very strongly clustered. If, as indicated by several lines of…
The extraordinarily bright quasar PHL 1811 at a redshift z = 0.192 provides an attractive opportunity to use ultraviolet absorption-line spectroscopy to study the properties of gas systems in the local universe. An R = 20,000 far-UV…
We present morphological and photometric properties of 79 low redshift (z<0.12) radio galaxies extracted from two radio flux limited samples of radio sources. All objects are imaged in the R band and for a subsample we have also obtained B…
We report on the results of deep narrow-band Ly-alpha, U and I imaging of the fields of two GRBs at z=2.04 (GRB 000301C and GRB 000926). We find that the host galaxy of GRB 000926 is an extended, strong Ly-alpha emitter with a rest-frame…
The V=16.9 quasar FBQ 0951+2635 at redshift z=1.24 appears double on CCD exposures taken in subarcsecond seeing. The two objects are separated by 1.1" and differ in brightness by 0.9 mag. VLA observations show the radio source to be double…
We present an imaging study of the black hole binary candidate SDSS J1536+0441 (z=0.3893), based on deep, high resolution VzK images collected at the ESO/VLT. The images clearly show an asymmetric elongation, indicating the presence of a…
We report the discovery of an extremely luminous galaxy lying at a redshift of z=5.74, SSA22-HCM1. The object was found in narrowband imaging of the SSA22 field using a 105 Angstrom bandpass filter centered at 8185 Angstroms during the…
We report the first detection of the host galaxy of a strong 2175 \AA$ $ dust absorber at z = 2.12 towards the background quasar SDSS J121143.42+083349.7 using HST/WFC3 IR F140W direct imaging and G141 grism spectroscopy. The…
The intense UV radiation from a highly luminous QSO should excite fluorescent Ly-alpha emission from any nearby neutral hydrogen clouds. We present a very deep narrow-band search for such emission near the z=2.168 quasar PKS 0424-131,…
(Abridged) A new technique for the spatial deconvolution of spectra is applied to near-IR (0.95 - 2.50 micron) NTT/SOFI spectra of the lensed, radio-quiet quasar HE 1104-1805. The continuum of the lensing galaxy is revealed between 1.5 and…
It is commonly accepted that radio-loud active galactic nuclei are hosted exclusively by giant elliptical galaxies. We analyze high-resolution optical Hubble Space Telescope images of a sample of radio galaxies with extended double-lobed…
We present K-band imaging and photometry of a sample of 52 radio loud quasars (RQs) selected from the B3 survey with flux densities above 0.5 Jy at 408 MHz. The optical completeness of the sample is 90% and the quasars cover the redshift…
The properties of satellite galaxies are closely related to their host galaxies in galaxy groups. In cluster environments, on the other hand, the interaction between close neighbors is known to be limited. Our goal is to examine the…
We investigate the luminosity evolution of the host galaxies of radio-loud AGN through Hubble Space Telescope imaging of 72 BL Lac objects, including new STIS imaging of nine z > 0.6 BL Lacs. With their intrinsically low accretion rates and…
Very deep ESO/VLT FORS1 and ISAAC images, as well as HST NICMOS2 data are used to infer the nature of the quasar pair LBQS 1429-0053 A and B, either a binary quasar or a doubly-imaged lensed quasar. Direct search of a putative lensing…
We report the discovery of a pair of quasars at $z=1.487$, with a separation of $8\farcs585\pm0\farcs002$. Subaru Telescope infrared imaging reveals the presence of an elliptical and a disk-like galaxy located almost symmetrically between…
We report the discovery of a new two-image gravitational lens candidate. The system RX J0921+4529 contains two z_s=1.66 quasars separated by 6."93 with an H band magnitude difference of $\Delta m=1.39$. The HST NIC2 H band images reveal an…
Observations of GRB host galaxies and their environments in general can provide valuable clues about the nature of progenitors. Bursts are associated with faint, <R> ~ 25 mag, galaxies at cosmological redshifts, <z> ~ 1. The host galaxies…
(abriged)In this paper we study different properties of quasars and their host galaxies at high redshifts up to z~3.4. We compare our results to those of other authors and discuss the correlation between galaxy evolution and quasar…
The HST snapshot imaging survey of 110 BL Lac objects (Urry et al. 2000) has clearly shown that the host galaxies are massive and luminous ellipticals. The dispersion of the absolute magnitudes is sufficiently small, so that the measurement…