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Related papers: DI in the outer Galaxy

200 papers

Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from the LiI 670.8nm line reveal a…

Hydrogen deuteride (HD) is prevalent in a wide variety of astrophysical environments, and measuring its large-scale distribution at different epochs can in principle provide information about the properties of these environments. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Patrick C. Breysse , Simon Foreman , Laura C. Keating , Joel Meyers , Norman Murray

The goal of this study is to measure parameters of the integrated HI emission for twenty-two dwarf galaxies with oxygen abundance 12+log(O/H) in the range of 7.42 to 7.65, which are representatives of the eXtremely Metal-Deficient (XMD)…

Astrophysics · Physics 2009-11-13 S. A. Pustilnik , J. -M. Martin

The Nitrogen-to-Oxygen (N/O) abundance ratio is an important diagnostic of galaxy evolution since the ratio is closely tied to the growth of metallicity and the star formation history in galaxies. Estimates for the N/O ratio are…

We present high-resolution radio observations of a sample of 65 radio sources at low Galactic latitudes. The sources were all observed at 5 GHz with the Very Large Array A-array. MERLIN observations at 5 GHz of the ultracompact HII region…

Astrophysics · Physics 2009-11-10 D. J. Saikia , P. Thomasson , S. Roy , A. Pedlar , T. W. B. Muxlow

Observations of neutral hydrogen can provide a wealth of information about the kinematics of galaxies. To learn more about the large scale structures and accretion processes, the extended environment of galaxies have to be observed.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Attila Popping , Robert Braun

Serendipitously we have discovered a rare, bright submillimeter galaxy (SMG) with a flux density of 30 +/- 2 mJy at lambda=1.2mm, using MAMBO2 at the IRAM 30-meter millimeter telescope. Although no optical counterpart is known for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. -F. Lestrade , F. Combes , P. Salome , A. Omont , F. Bertoldi , P. Andre , N. Schneider

The main objective of this work is to derive the distribution of the the metal content of HII galaxies using sulphur as an abundance tracer. This increases the metallicity range that can safely be reached. We selected a sample of…

Astrophysics of Galaxies · Physics 2025-01-14 Marta Gavilán , Ángeles I. Díaz , Sandra Zamora

There has been great progress in recent years in discovering star forming galaxies at high redshifts (z>5), close to the epoch of reionization of the intergalactic medium (IGM). The WFC3 and ACS cameras on the Hubble Space Telescope have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Andrew Bunker

Analyses of spectra obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, together with spectra from the Copernicus and IMAPS instruments, reveal an unexplained very wide range in the observed deuterium/hydrogen (D/H)…

Low-mass or dwarf galaxies (M$_{\ast}<10^{9}$ M${\odot}$) are abundant in the Universe, yet their formation and evolution remain poorly understood. Their enhanced sensitivity to feedback from star formation and active galactic nuclei (AGN)…

Contemporary research suggests that the reionisation of the intergalactic medium (IGM) in the early Universe was predominantly realised by star-forming (proto-)galaxies (SFGs). Due to observational constraints, our knowledge on the origins…

Astrophysics of Galaxies · Physics 2023-03-29 Adam U. Enders , Dominik J. Bomans , Anna Wittje

A search for HI absorption has been made in 23 radio galaxies using the ATCA, the VLA and the WSRT. In five galaxies HI absorption was detected. We investigate how the detection rate is distributed among galaxies with different radio and…

Astrophysics · Physics 2009-10-31 R. Morganti , T. A. Oosterloo , C. N. Tadhunter , G. van Moorsel , N. Killeen , K. A. Wills

One of the major conundrums in contemporary extragalactic astrophysics is the apparent overabundance of a remarkable population of UV-bright galaxies at redshifts $z\gtrsim 9$. We analyse galaxies spectroscopically observed by JWST/NIRSpec…

We have obtained VLA and optical follow-up observations of the low-velocity H I source HIZSS 3 discovered by Henning et al. (2000) and Rivers (2000) in a survey for nearby galaxies hidden by the disk of the Milky Way. Its radio…

Astrophysics · Physics 2009-11-10 Philip Massey , P. A. Henning , R. C. Kraan-Korteweg

Prestellar cores represent the initial conditions of star formation, but heavy molecules such as CO are strongly depleted in their cold, dense interiors, limiting the ability to probe core centers. Deuterated molecular ions therefore emerge…

We report the results of a survey of low mass Class I protostars in the cm continuum. In the initial survey, seven sources in the Taurus star formation were observed with the VLA at 0``.25 resolution. All seven sources drive CO outflows and…

Astrophysics · Physics 2015-06-24 P. W. Lucas , Katherine M. Blundell , P. F. Roche

We present a measurement of the deuterium to hydrogen ratio (D/H) in a metal-poor absorption system at redshift $z=2.504$ towards the QSO 1009+2956. We apply the new method of Burles & Tytler (1997) to robustly determine D/H in high…

Astrophysics · Physics 2008-11-26 Scott Burles , David Tytler