Results 21 to 30 of about 43,858 (281)
A Neutral Hydrogen Cloud in the Vicinity of the Elliptical Galaxy NGC 4318 [PDF]
Symposium - International Astronomical Union, 1987 NGC 4318, in the Virgo Cluster, has the following optical properties: —morphological type: E (Nilson, 1973)—BoT magnitude : 13.8 (Nilson, 1973)—photometric axis : 0.8′ × 0.6′ (Nilson, 1973)—heliocentric radial velocity: −300 km s−1 (Arakelian et al., 1975)1247± 15 km s (Tonry, 1981)1215 km s−1 (Huchra et al., 1983)
Bottinelli, L. +2 more
openaire +2 more sources
A Neutral Hydrogen Self-Absorption Cloud in the SGPS
The Astrophysical Journal, 2003 Using data from the Southern Galactic Plane Survey (SGPS) we analyze an HI self-absorption cloud centered on l = 318.0 deg, b = -0.5 deg, and velocity, v = -1.1 km/s. The cloud was observed with the Australia Telescope Compact Array (ATCA) and the Parkes Radio Telescope, and is at a near kinematic distance of less than 400 pc with derived dimensions of
Kavars, D. W. +4 more
openaire +3 more sources
On the Ionisation of Warm Opaque Interstellar Clouds and the Intercloud Medium [PDF]
, 1997 In this paper we use a number of observations to construct an integrated picture of the ionisation in the interiors of quiescent warm opaque interstellar clouds and in the intercloud medium (ICM) outside dense HII regions and hot dilute bubbles. Our main
Binney J. J. +5 more
core +2 more sources
H i in Molecular Clouds: Irradiation by FUV Plus Cosmic Rays
The Astrophysical Journal, 2023 We extend the analytic theory presented by Sternberg et al. and Bialy & Sternberg for the production of atomic hydrogen (H i ) via far-ultraviolet (FUV) photodissociation at the boundaries of dense interstellar molecular (H _2 ) clouds to also include ...
Amiel Sternberg +2 more
doaj +1 more source
A Search for OH 18 cm Emission from Intermediate-velocity Gas at High Galactic Latitudes
The Astrophysical Journal, 2023 We present search results of 22 high-latitude (∣ b ∣ > 25°) sightlines for OH 18 cm emission using the 305 m radio telescope at the Arecibo Observatory. These sightlines appear in neutral hydrogen emission at intermediate velocities −90 ≤ V _LSR ≤ −20 km
Allison J. Smith, D. Anish Roshi
doaj +1 more source
Two-component model of the interaction of an interstellar cloud with surrounding hot plasma
, 2011 We present a two-component gasdynamic model of an interstellar cloud embedded in a hot plasma. It is assumed that the cloud consists of atomic hydrogen gas, interstellar plasma is quasineutral.
Baranov +23 more
core +2 more sources
IMAPS Observations of Interstellar Neutral Argon and the Implications for Partially Ionized Gas [PDF]
, 1997 We use the absorption features from neutral argon at 1048 and 1066 A to determine interstellar abundances or their lower limits toward nine early-type stars. These features were observed with the Interstellar Medium Absorption Profile Spectrograph (IMAPS)
Ajello J. M. +20 more
core +3 more sources
Low-Metallicity Gas Clouds in a Galaxy Proto-Cluster at Redshift 2.38
, 2004 We present high resolution spectroscopy of a QSO whose sight-line passes through the halo of a pair of elliptical galaxies at redshift 2.38. This pair of galaxies probably lies at the center of a galaxy proto-cluster, and is embedded in a luminous ...
Chiosi C. +4 more
core +1 more source
On the chemistry of hydrides of N atoms and O$^+$ ions [PDF]
, 2016 Previous work by various authors has suggested that the detection by Herschel/HIFI of nitrogen hydrides along the low density lines of sight towards G10.6-0.4 (W31C) cannot be accounted for by gas-phase chemical models.
Awad, Zainab +2 more
core +2 more sources