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Related papers: An Evolutionary Sequence of Expanding Hydrogen She…

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This is the third paper in a series in which we attempt to put constraints on the flattening of dark halos in disk galaxies. For this purpose we need to analyse the observed XV diagrams in edge-on galaxies to accurately measure the radial…

Astrophysics of Galaxies · Physics 2015-05-18 J. C. O'Brien , K. C. Freeman , P. C. van der Kruit

We present VLA H I imaging data for a field in the NW of the galaxy cluster Abell 1367 (z = 0.02) in an attempt to probe the effect environment has on the interstellar medium of late-type spiral galaxies. Several galaxies show pronounced…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 T. C. Scott , H. Bravo-Alfaro , E. Brinks , C. A. Caretta , L. Cortese , A. Boselli , M. J. Hardcastle , J. H. Croston , I. Plauchu

Observations of intergalactic neutral hydrogen can provide a wealth of information about structure and galaxy formation, potentially tracing accretion and feedback processes on Mpc scales. Below a column density of NHI ~ 10^19 cm-2, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Attila Popping , Romeel Dave , Robert Braun , Benjamin D. Oppenheimer

We present an analysis of the neutral hydrogen (HI) properties of a fully cosmological hydrodynamical dwarf galaxy, run with varying simulation parameters. As reported by Governato et al. (2010), the high resolution, high star formation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 K. Pilkington , B. K. Gibson , F. Calura , A. M. Brooks , L. Mayer , C. B. Brook , G. S. Stinson , R. J. Thacker , C. G. Few , D. Cunnama , J. Wadsley

We have mapped the emission from atomic hydrogen at 21 cm from the galaxy NGC 3783 with the Australia Telescope Compact Array. Our main results are: a) the HI morphology is irregular and perturbed, gathered in three blobs apparently…

Astrophysics · Physics 2007-05-23 J. A. Garcia-Barreto , F. Combes , B. Koribalski , J. Franco

We present excellent resolution and high sensitivity Very Large Array (VLA) observations of the 21cm HI line emission from the face-on galaxy NGC 1058, providing the first reliable study of the HI profile shapes throughout the entire disk…

Astrophysics · Physics 2009-06-23 A. O. Petric , M. P. Rupen

We present an imaging study of a sample of eight asymptotic giant branch (AGB) stars in the HI 21-cm line. Using observations from the Very Large Array, we have unambiguously detected HI emission associated with the extended circumstellar…

Solar and Stellar Astrophysics · Physics 2015-06-12 L. D. Matthews , T. Le Bertre , E. Gerard , M. C. Johnson

We consider an all-sky sample of 1029 Local Volume (LV) galaxies situated within a distance of 11 Mpc. Their majority have precise distances, estimates of hydrogen mass fraction and star-formation rate derived from far-ultraviolet or Halpha…

Astrophysics of Galaxies · Physics 2018-07-18 I. D. Karachentsev , E. I. Kaisina , D. I. Makarov

We present high resolution (R ~ 4 km/s) absorption measurements of the interstellar NaI and CaII lines measured towards 14 early-type stars of distance 123 pc - 1650 pc, located in the direction of the Ara OB1 stellar cluster. The line…

Astrophysics · Physics 2009-06-23 Christopher D. Henderson , Barry Y. Welsh , John B. Hearnshaw

A sample of 69 galaxies with radial velocities less than 2500 km/s was selected from the HI Parkes All Sky Survey (HIPASS) to deduce details about star formation in nearby disk galaxies selected with no bias to optical surface brightness…

Astrophysics · Physics 2009-11-11 J. F. Helmboldt , R. A. M. Walterbos , G. D. Bothun , K. O'Neil

Shells are fine stellar structures identified by their arc-like shapes present around a galaxy and currently thought to be vestiges of galaxy interactions and/or mergers. The study of their number, geometry, stellar populations and gas…

Astrophysics of Galaxies · Physics 2019-10-02 Brisa Mancillas , Francoise Combes , Pierre-Alain Duc

We present a study of the filamentary structure in the atomic hydrogen (HI) emission at the 21 cm wavelength toward the Galactic plane using the observations in the HI4PI survey. Using the Hessian matrix method across radial velocity…

Circumstellar shells around AGB stars are built over long periods of time that may reach several million years. They may therefore be extended over large sizes (~1 pc, possibly more), and different complementary tracers are needed to…

Astrophysics · Physics 2009-11-13 Y. Libert , T. Le Bertre , E. Gérard , J. M. Winters

We consider global HI and optical properties of about three hundred nearby galaxies with V$_0 < 500$ km/s. The majority of them have individual photometric distance estimates. The galaxy sample parameters, e.g. their linear diameters, their…

Astrophysics · Physics 2023-04-19 I. D. Karachentsev , D. I. Makarov , W. K. Huchtmeier

We present and discuss the properties of an ionized component with extreme kinematics in an off-nuclear HII region located at 0.8 - 1.0 kpc from the nucleus of SDSS J143245.98+404300.3, recently reported in Rodriguez del Pino et al. (2019).…

We present 21-cm observations and models of the HI kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. Our models give insight into…

Astrophysics of Galaxies · Physics 2011-07-21 Laura K. Zschaechner , Richard J. Rand , George H. Heald , Gianfranco Gentile , Peter Kamphuis

We use 666 blue horizontal branch (BHB) stars from the 2Qz redshift survey to map the Galactic halo in four dimensions (position, distance and velocity). We find that the halo extends to at least 100 kpc in Galactocentric distance, and…

Astrophysics of Galaxies · Physics 2015-05-19 Roberto De Propris , Craig D. Harrison , Peter J. Mares , CTIO , Cornell University

Growing evidence supports the suggestion that the compact high-velocity clouds of HI (CHVCs) are located throughout the Local Group and continue to fuel galactic evolution. Recent distance estimates to individual objects lie in the range…

Astrophysics · Physics 2009-10-31 Robert Braun , W. Butler Burton

We perform for the first time a 3D hydrodynamics simulation of the evolution of the last minutes pre-collapse of the oxygen shell of a fast-rotating massive star. This star has an initial mass of 38 M$_\odot$, a metallicity of $\sim$1/50…

Solar and Stellar Astrophysics · Physics 2021-07-01 Takashi Yoshida , Tomoya Takiwaki , David R. Aguilera-Dena , Kei Kotake , Koh Takahashi , Ko Nakamura , Hideyuki Umeda , Norbert Langer

Galaxies in the local Universe are thought to require ongoing replenishment of their gas reservoir in order to maintain the observed star formation rates. Cosmological simulations predict that such accretion can occur in both a dynamically…

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