相关论文: The complex structure of the Mg II {\lambda\lambda…

We describe a search for MgII(2796,2803) absorption lines in Sloan Digital Sky Survey (SDSS) spectra of QSOs whose lines of sight pass within impact parameters of 200 kpc of galaxies with photometric redshifts of z=0.46-0.6 and redshift…

We investigate the physical properties of large-scale wind structures around massive hot stars with radiatively-driven winds. We observe Discrete Absorption Components (DACs) in optical He I P Cygni lines of the LBV binary MWC 314…

First results from a study of high ionization absorption properties in roughly 30 Mg II absorption selected galaxies are presented. We have tested for correlations of Mg II, C IV, Si IV, N V, and O VI equivalent widths with the galaxy…

We present extensive metal-line absorption properties for 45 absorption systems that were selected by their Mg II absorption at redshifts between 0.4 and 1.4. For each system the properties of several chemical species are determined,…

Using a sample of nearly 700 quasars with strong (W_0(2796)>0.8 Angstrom) MgII absorption lines detected in the Early Data Release of the SDSS, we demonstrate the feasibility of measuring the photometric properties of the absorber systems…

We present r'- or i'-band WIYN images of the fields of 15 Sloan Digital Sky Survey quasars that have spectra exhibiting intervening MgII absorption-line systems with rest equivalent widths 2.7A \le REW \le 6.0A and redshifts 0.42 < z_{abs}…

We study the frequency of Mg II absorption in the outer haloes of galaxies at z = 0.6 - 1.4 (with median z = 0.87), using new spectra obtained of ten background quasars with galaxy impact parameters of b < 100 kpc. The quasar sightlines…

We present an initial survey of Mg II absorption characteristics in the halos of a carefully constructed, volume-limited subsample of galaxies embedded in the spectroscopic part of the Sloan Digital Sky Survey. We observed quasars near…

We present the results of photoionization modeling of nine weak MgII (W_r<0.3 Ang) quasar absorption line systems with redshifts 1.4<z<2.4 obtained with the Ultraviolet and Visual Echelle Spectrograph on the Very Large Telescope. These…

1.02-1.16 micron spectra (R ~ 7,000) of the gravitationally lensed QSO APM 08279+5255 at z_em=3.911 were obtained during the commissioning run of IRCS, the 1-5 micron near-infrared camera and spectrograph for the Subaru 8.2 m Telescope.…

We present HIRES/Keck profiles of four extremely strong (W_r > 1.8 A) Mg II absorbers at 1 < z < 2. The profiles display a common kinematic structure, having a sharp drop in optical depth near the center of the profile and strong,…

We discuss issues concerning the physical nature of intervening MgII quasar absorption systems in light of results from our recent surveys using SDSS EDR QSO spectra and data obtained at the MMT. These surveys indicate an excess of weak…

[Abridged] We examine a sample of 45 Mg II absorption-selected systems over the redshift range 0.4 to 1.4. Mg II and Fe II absorption profiles were observed at a resolution of ~6 km/s with HIRES/Keck. Lyman-alpha and C IV data were measured…

High spectral resolution ISO-LWS observations of the [OI] 63.2 and 145.5 microns and [CII] 157.7 microns fine structure lines are presented for the center of the Sagittarius B2 complex (SgrB2). Both the [OI] 63.2 microns and the [CII] 157.7…

We analyze the cross-correlation of 2,705 unambiguously intervening Mg II (2796,2803A) quasar absorption line systems with 1,495,604 luminous red galaxies (LRGs) from the Fifth Data Release of the Sloan Digital Sky Survey within the…

The increasing availability of high quality spectra of QSO absorption line systems at resolutions of only a few km/s is expected to facilitate the translation of the kinematics of components comprising the lines into the spatial…

Studying the stellar mass, age, luminosity, star-formation rate, and impact parameter of quasar absorber host galaxies can aid in the understanding of galaxy formation and evolution as well as in testing their models. We derive the Spectral…

We investigate the structure of the Mg II broad line emission region in a sample of 284 Type 1 active galactic nuclei (AGNs), through comparing the kinematical parameters of the broad Mg II and broad H$\beta$ lines. We found that the Mg II…

The physical origin of the large-scale conformity in the colours and specific star formation rates of isolated low mass central galaxies and their neighbours on scales in excess of 1 Mpc is still under debate. One possible scenario is that…

The intervening z=0.7443 Mg II absorption system in the spectrum of MC 1331+170 shows an unusual series of line pairs, each with velocity separations of 30 km/s. These lines could be explained as the shells of expanding superbubbles…