相关论文: A Group of Galaxies at Redshift 2.38
We report the discovery of a highly significant concentration of galaxies at a redshift of <z>=3.090. The structure is evident in a redshift histogram of photometrically selected ``Lyman break'' objects in a 9' by 18' field in which we have…
We present new GHRS observations of Lyman alpha absorption lines associated with a group of galaxies towards the QSO 1545+2101. We have identified eight distinct Lyman alpha absorption features in the spectrum of QSO 1545+2101 at a mean…
We present the results of deep Lyman limit imaging in four new fields as part of a continuing search for galaxies at $3.0 \le z \le 3.5$. The technique uses a custom broad--band filter set ($U_n G {\cal R}$) designed to isolate objects…
Eighteen candidates for emission line galaxies were discovered in a narrow-band infrared survey that targeted the redshifts of damped Lyman-alpha or metal lines in the spectra of quasars. The presence of emission lines is inferred from the…
We report the discovery of a high redshift, narrow emission-line galaxy identified in the optical follow-up of deep ROSAT fields. The object has a redshift of z=2.35 and its narrow emission lines together with its high optical and X-ray…
We describe the properties of a system of red arcs discovered at z=4.04 around the cluster A2390 ($z=0.23$). These arcs are images of a single galaxy, where the lensing is compounded by an elliptical cluster member lying close to the…
We present a redshift z=6.535 galaxy discovered by its Lyman alpha emission in a 9180A narrowband image from the Large Area Lyman Alpha (LALA) survey. The Ly-a line luminosity (1.1e43 erg/s) is among the largest known for star forming…
We have measured the 2D 2-point correlation function, Xi_AG, between low column density Ly-alpha absorbers and galaxies at a redshift z ~ 1. We measured Ly-alpha absorbers between redshifts z=0.68 to 1.51 over a total redshift path length…
The Lynx arc, with a redshift of 3.357, was discovered during spectroscopic follow-up of the z=0.570 cluster RX J0848+4456 from the ROSAT Deep Cluster Survey. The arc is characterized by a very red R-K color and strong, narrow emission…
Near-infrared imaging and spectroscopy have been obtained of the gravitationally lensed galaxy at z=4.92 discovered in HST images by Franx et al. (1997). Images at 1.2, 1.6 and 2.2 microns show the same arc morphology as the HST images. The…
The most remarkable class of high-redshift objects observed so far is extended Ly$\alpha$ emission-line blobs found in an over-density region at redshift 3.1. They may be either a dust-enshrouded, extreme starburst galaxy with a large-scale…
(ABRIDGED) Gaseous halos of nine nearby galaxies (with redshifts cz < 6000 km/s) were probed at large galactocentric radii using background quasars observed with HST GHRS and STIS. The projected quasar-galaxy separations range from 55 to…
We report the serendipitous discovery of two objects close in projection with fairly strong emission lines at long wavelength (~9190 A). One (A) seems not to be hosted by any galaxy brighter than V(555)=27.5, or I(814)=26.7 (Vega-based…
We report on the detection of a z_gal=0.101 galaxy projected on the sky at 4.2 arcsec (or 5.2 h^{-1} kpc for q_o=0.5) from the quasar Q 0439-433 (z_em=0.594). The HST spectrum of the quasar shows strong MgII, FeII, SiII, AlII and CIV…
We present spectroscopic observations obtained with the ESO Very Large Telecope (VLT) of seven candidate Ly-alpha emitting galaxies in the field of the radio quiet Q1205-30 at z=3.04 previously detected with deep narrow band imaging. Based…
Imaging at 1.25 and 2.20 microns has been obtained of the field containing the galaxy (RD1) found at redshift 5.34 by Dey et al.(1998). This galaxy has been detected at 1.25 microns, while the lower redshift (z=4.02) galaxy also found in…
VLT spectroscopic observations of Ly alpha--excess objects in the field of the clumpy radio galaxy 1138-262 at z=2.16 have led to the discovery of 14 galaxies and one QSO at approximately the same distance as the radio galaxy. All galaxies…
We summarise the results of a deep search for Lyman alpha emission from star-forming regions associated with damped Lyman alpha absorption systems and conclude that the Lyman alpha luminosity of high redshift galaxies is generally less than…
To study the nature of low z Lya absorbers in the spectra of QSOs, we have obtained high signal-to-noise UV spectra of H 1821+643 (z = 0.297) and PG 1116+215 (z = 0.177) with the GHRS on the HST. The spectra have minimum S/N of 70-100 and 3…
Spatially extended Ly-alpha sources which are faint and compact in coninuum are candidates for extremely young galaxies (age of ~<10e+7 yrs) at high redshifts. We carried out a systematic survey for extended Ly-alpha sources, using deep…