相关论文: A Group of Galaxies at Redshift 2.38
The lack of success of Lyman-alpha searches for high-redshift (z>2) field galaxies may be due to extinction by dust, suggesting that surveys based on lines of longer wavelength, particularly H-alpha, may be more effective. To test the dust…
We use JWST observations (1.5 micron to 4.44 micron), together with complete ALMA observations (870 micron and/or 1.2 mm), of the massive lensing cluster field A2744 to show that galaxies between z=1.5 and z=5.5 with rest-frame red colors…
We study the galaxy number density (smoothed on a 5h^{-1} Mpc scale) around 18 low-redshift Lyman-alpha absorbers previously observed with HST. The absorbers lie in the foregrounds of Mrk 335, Mrk 421, Mrk 501, I Zw 1, and 3C 273, all…
We study the average Ly$\alpha$ emission associated with high-$z$ strong (log $N$(H I) $\ge$ 21) damped Ly$\alpha$ systems (DLAs). We report Ly$\alpha$ luminosities ($L_{\rm Ly\alpha}$) for the full as well as various sub-samples based on…
We present grism spectra taken with the Advanced Camera for Surveys to identify 29 red sources with (i'-z') > 0.9 in the Hubble Ultra Deep Field (HUDF). Of these 23 are found to be galaxies at redshifts between z=5.4 and 6.7, identified by…
We present results from a spectroscopic and imaging survey of galaxies in the fields of quasars from the HST Quasar Absorption Line Key Project. The aim of this survey is to identify galaxies within 3.5' from the quasar sightline, to a…
In the early Universe finding massive galaxies that have stopped forming stars present an observational challenge as their rest-frame ultraviolet emission is negligible and they can only be reliably identified by extremely deep…
The spatial distribution of Ly-alpha forest absorption systems toward a group of 8, closely spaced QSOs has been analysed and evidence for large scale structure has been found at <z> = 2.8. Our technique is based on the first and second…
We present a detailed study of the emission from a z = 2.35 galaxy that causes damped Lyman-alpha absorption in the spectrum of the background QSO, SDSS J 2222-0946. We present the results of extensive analyses of the stellar continuum…
Narrow-band imaging surveys aimed at detecting the faint emission from the 5007 [O III] line of intracluster planetary nebulae in Virgo also probe high redshift z=3.1 Ly alpha emitters. Here we report on the spectroscopic identification of…
Radio galaxy PKS 1138-262 is a massive galaxy at z=2.16, located in a dense environment. We have found an overdensity of Ly-alpha emitting galaxies in this field, consistent with a proto-cluster structure associated with the radio galaxy.…
We present a survey for low-ionization metal absorption line systems towards 17 QSOs at redshifts z_em=5.8-6.4. Nine of our objects were observed at high resolution with either Keck/HIRES or Magellan/MIKE, and the remainder at moderate…
We have carried out a study of the luminosity function (henceforth LF) of galaxies in the region of the HDF-North using our very complete redshift catalog. We solve for the LF at four rest frame wavelengths from 0.24 to 2.2mu. We find that…
We confirm spectroscopically the existence of a population of galaxies at z>~2 with rest-frame optical colors similar to normal nearby galaxies. The galaxies were identified by their red near-infrared colors in deep images obtained with…
In this work we shall sketch a further piece of evidence for the plausibility of hypothesis of galactic origin of Ly-$\alpha$ forest absorption systems. Two basic premises of our discussion are (1) HDF redshift surface densities in the…
We discovered a sample of 250 Ly-Alpha emitting (LAE) galaxies at z=2.1 in an ultra-deep 3727 A narrow-band MUSYC image of the Extended Chandra Deep Field-South. LAEs were selected to have rest-frame equivalent widths (EW) > 20 A and…
We report the discovery of a new gravitationally lensed QSO, at a redshift z = 1.689, with four QSO components in a cross-shaped arrangement around a bright galaxy. The maximum separation between images is 2.6 arcsec, enabling a reliable…
Laporte et al. (2011) reported a very high redshift galaxy candidate: a lensed J-band dropout (A2667-J1). J1 has a photometric redshift of z=9.6-12, the probability density function for which permits no low or intermediate z solution. We…
Due to the invention of new powerful instruments in the recent past (e.g. 10m class telescopes) high redshift galaxies are no longer a curiosity. High redshift young star forming galaxies can be effectively discriminated from the much more…
We report the discovery and spectroscopic confirmation of three gravitationally-lensed images of a galaxy at z=3.9 in the background of a distant, rich cluster of galaxies at z=0.83, on the basis of observations with Faint Object Camera And…