相关论文: Glimpses of the Interstellar Medium at Redshift 3.…
We have obtained Keck HIRES spectra of three images of the gravitationally lensed QSO 2237+0305 to study low ionization absorption systems and their differences in terms of projected velocity and column density across the lines of sight. We…
Keck HIRES spectra were obtained of the separate images of three gravitationally lensed QSOs (UM 673, Q1104-1804, and Q1422+2309). We studied the velocity and column density differences in CIV doublets in each QSO. Unlike the low ionization…
We examine the relationship between galaxies and the intergalactic medium at z < 1 using a group of three closely spaced background QSOs with z_em ~1 observed with the Hubble Space Telescope. Using a new grouping algorithm, we identify…
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…
Spectra from the Keck HIRES instrument of the Lyman alpha forests in the lines of sight to the A and C components of the gravitationally lensed QSO Q1422+231 were used to investigate the structure of the intergalactic medium at mean…
Absorption-line spectroscopy of multiply-lensed QSOs near a known foreground galaxy provides a unique opportunity to go beyond the traditional one-dimensional application of QSO probes and establish a crude three-dimensional (3D) map of…
We present the first results from a survey of the relative spatial distributions of galaxies, intergalactic neutral hydrogen, and intergalactic metals at high redshift. We obtained high-resolution spectra of 8 bright QSOs at 3.1<z<4.1 and…
We report the discovery of a strong CIV 1548,1550 absorption system at z_abs = 5.7238 in the near-infrared spectrum (J-band) of the z_em = 6.28 QSO SDSS J1030+0524. These observations, obtained with the Infrared Spectrometer And Array…
We present new H I 21 cm absorption data and ultraviolet spectroscopy from HST/STIS of the QSO/galaxy pair 3C 232/NGC 3067. The QSO sightline lies near the minor axis and 1.8 arcmin (11 kpc) above the plane of NGC 3067, a nearby luminous…
(Abridged) This paper presents an absorption-line study of the multiphase circumgalactic medium (CGM) based on observations of Lya, CII, CIV, SiII, SiIII, and SiIV absorption transitions in the vicinities of 195 galaxies at redshift…
We have recently identified several high velocity (V < -100 km/s) clouds in the directions of Mrk 509 and PKS 2155-304 that have unusual ionization properties. The clouds exhibit strong C IV absorption with little or no detectable low ion…
We present multi-sightline absorption spectroscopy of cool gas around three lensing galaxies at z=0.4-0.7. These lenses have half-light radii r_e=2.6-8 kpc and stellar masses of log M*/Ms=10.9-11.4, and therefore resemble nearby passive…
We present Goddard High Resolution Spectrograph and ORFEUS-II measurements of Si IV, CIV, N V, and O VI absorption in the interstellar medium of the Galactic disk and halo toward the nucleus of the Seyfert galaxy ESO141-055. The high…
We present an analysis of the molecular and atomic gas emission in the rest-frame far-infrared and sub-millimetre, from the lensed z=2.3 sub-millimetre galaxy SMM J2135-0102. We obtain very high signal-to-noise detections of 11 transitions…
We report the results of a study of the rest-frame UV spectrum of the Cosmic Eye, a luminous Lyman break galaxy at z=3.07331 gravitationally lensed by a factor of 25. The spectrum, recorded with the ESI spectrograph on the Keck II…
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…
Using Voigt-profile-fitting procedures on Keck HIRES spectra of nine QSOs we identify 1099 CIV absorber components clumped in 201 systems outside the Lyman forest over 1.6 < z < 4.4. With associated SiIV, CII, SiII and NV where available we…
We study the internal structure of the Circum-Galactic Medium (CGM), using 29 spectra of 13 gravitationally lensed quasars with image separation angles of a few arcseconds, which correspond to 100 pc to 10 kpc in physical distances. After…
We present results from 12 km/s resolution echelle spectroscopy of the bright $z=4.694$ QSO BR1202-0725. A preliminary analysis shows that high metallicity narrow line absorption clouds are present up to the redshift of the quasar. A damped…
Absorption-line spectroscopy of 23 background QSOs and numerous background galaxies has let us measure the spatial distribution of metals and neutral hydrogen around 1044 UV-selected galaxies at redshifts 1.8<z<3.3. The typical galaxy is…