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Related papers: Variable Interstellar Absorption toward the Halo S…

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Recent spectroscopic observations of intermediate- and high-velocity clouds (IVCs and HVCs) in the Milky Way halo have unveiled the presence of diffuse interstellar molecular hydrogen (H_2) several kpc away from the Galactic disk. Most of…

Astrophysics · Physics 2007-05-23 Philipp Richter

We discuss moderate resolution spectra of the NaD absorption-line in a sample of 32 far-IR-bright starburst galaxies. In 18 cases, the line is produced primarily by interstellar gas, and in 12 of these it is blueshifted by over 100 km/s…

Astrophysics · Physics 2009-10-31 Timothy M. Heckman , Matthew D. Lehnert , David K. Strickland , Lee Armus

We have directly compared MgII halo gas kinematics to the rotation velocities derived from emission/absorption lines of the associated host galaxies. Our 0.096<z<0.148 volume-limited sample comprises 13 ~L* galaxies, with impact parameters…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 G. G. Kacprzak , C. W. Churchill , E. J. Barton , J. Cooke

(ABRIDGED) We present a Far-Ultraviolet Spectroscopic Explorer survey of highly ionized high-velocity clouds (HVCs) in 66 extragalactic sight lines. We find a total of 63 high-velocity O VI absorbers, 16 with 21 cm-emitting H I counterparts…

Astrophysics · Physics 2009-11-11 Andrew J. Fox , Blair D. Savage , Bart P. Wakker

A new molecular hydrogen cloud is found in the sub-damped Ly-alpha absorber [log N(HI)=19.88+/-0.05] at the redshift z=1.15 toward the bright quasar HE0515-4414 (zem = 1.71). More than 30 absorption features in the Lyman band system of H2…

Astrophysics · Physics 2009-11-10 D. Reimers , R. Baade , R. Quast , S. A. Levshakov

We present high resolution (R~75,000), high signal-to-noise (S/N~100) Ca II $\lambda$3933.663 and Na I $\lambda\lambda$5889.951, 5895.924 spectra of 68 stars in the direction of the Vela supernova remnant. The spectra comprise the most…

Astrophysics · Physics 2009-10-31 Alexandra N. Cha , Kenneth R. Sembach

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…

Astrophysics · Physics 2009-11-07 M. Rauch , W. L. W. Sargent , T. A. Barlow , R. A. Simcoe

We have used the Arecibo telescope to carry out an survey of 31 dark clouds in the Taurus/Perseus region for narrow absorption features in HI ($\lambda$ 21cm) and OH (1667 and 1665 MHz) emission. We detected HI narrow self--absorption…

Astrophysics · Physics 2009-11-07 Di Li , Paul F. Goldsmith

We present high-resolution observations of interstellar CN, CH, CH^{+}, \ion{Ca}{1}, and \ion{Ca}{2} absorption lines toward the multiple star systems HD206267 and HD217035. Substantial variations in CN absorption are observed among three…

Astrophysics · Physics 2009-11-07 K. Pan , S. R. Federman , D. E. Welty

Na I D lines in the spectrum of the young binary KH 15D have been analyzed in detail. We find an excess absorption component that may be attributed to foreground interstellar absorption, and to gas possibly associated with the solids in the…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Lawler , W. Herbst , S. Redfield , C. M. Hamilton , C. M. Johns-Krull , J. N. Winn , J. A. Johnson , R. Mundt

An independent analysis of the molecular hydrogen absorption system at z = 2.059 in the spectrum of the quasar J2123-0050 is presented. The H_2 system consists of two components (A and B) with column densities log N^A(H_2) = 17.94+/-0.01…

Astrophysics of Galaxies · Physics 2016-03-07 V. V. Klimenko , S. A. Balashev , A. V. Ivanchik , D. A. Varshalovich

We present results of a blind search for Galactic HI 21-cm absorption lines toward 19130 radio sources, using 390 pointings of MALS, each pointing centered on a source brighter than 200 mJy. We detected 3640 HI absorption features. This…

The neutral hydrogen and the ionized helium absorption in the spectra of quasars are unique probes of structure in the early universe. We present Far-Ultraviolet Spectroscopic Explorer observations of the line of sight to the quasar…

Hydrogen column densities inferred from X-ray absorption are typically 5 - 30 times larger than the neutral atomic hydrogen column densities derived from 21cm HI absorption toward radio-loud active galactic nuclei. Some part of the…

Astrophysics of Galaxies · Physics 2021-02-24 Harvey Liszt

We present a detailed analysis of narrow of NaI and KI absorption resonance lines toward nearly 40 T Tauri stars in Taurus with the goal of clarifying their origin. The NaI 5889.95 angstrom line is detected toward all but one source, while…

Earth and Planetary Astrophysics · Physics 2015-11-18 I. Pascucci , S. Edwards , M. Heyer , E. Rigliaco , L. Hillenbrand , U. Gorti , D. Hollenbach , M. N. Simon

We report the detection of 21-cm HI absorption towards the core of the Fanaroff-Riley II radio galaxy 3C452 (J2245+3941). The absorption profile is well resolved into three components; the strongest and narrowest component being coincident…

Astrophysics · Physics 2009-11-11 Neeraj Gupta , D. J. Saikia

We report an accurate distance of d = 10+/-2.5kpc to the high-velocity cloud Complex C. Using high signal-to-noise Keck/HIRES spectra of two horizontal-branch stars, we have detected CaII K absorption lines from the cloud. Significant…

Astrophysics · Physics 2009-11-13 C. Thom , J. E. G. Peek , M. E. Putman , Carl Heiles , K. M. G. Peek , R. Wilhelm

We present a detailed analysis of a H2-bearing metal-rich sub-damped Lyman-alpha system at zabs = 0.10115 towards the radio-loud quasar J0441-4313, at a projected separation of ~7.6 kpc from a star-forming galaxy. The H2, C I and Na I…

Astrophysics of Galaxies · Physics 2015-06-23 R. Dutta , R. Srianand , S. Muzahid , N. Gupta , E. Momjian , J. Charlton

In the previous papers in this series, we have measured the stellar and \hi content in a sample of edge-on galaxies. In the present paper, we perform a simultaneous rotation curve and vertical force field gradient decomposition for five of…

Astrophysics of Galaxies · Physics 2016-10-26 S. P. C. Peters , P. C. van der Kruit , R. J. Allen , K. C. Freeman