English
Related papers

Related papers: A Galactic Plane Defined by the Milky Way HII Regi…

200 papers

Orbital properties of stars, computed from their six-dimensional phase space measurements and an assumed Galactic potential, are used to understand the structure and evolution of the Galaxy. Stellar actions, computed from orbits, have the…

We present a new, detailed, analysis of the spatial distribution of Galactic HII regions, exploiting a far richer database than used in previous analyses. Galactocentric distances have been derived for 550 objects. Distances from the Sun…

Astrophysics · Physics 2009-11-10 R. Paladini , G. DeZotti , R. D. Davies

The distribution of various interstellar gas components and the pressure in the interstellar medium (ISM) is a result of the interplay of different dynamical mechanisms and energy sources on the gas in the Milky Way. The scale heights of…

Astrophysics of Galaxies · Physics 2015-06-19 W. D. Langer , J. L. Pineda , T. Velusamy

We report the discovery of nineteen new HI shells in the Southern Galactic Plane Survey (SGPS). These shells, which range in radius from 40 pc to 1 kpc, were found in the low resolution Parkes portion of the SGPS dataset, covering Galactic…

Astrophysics · Physics 2009-11-07 N. M. McClure-Griffiths , John M. Dickey , B. M. Gaensler , A. J. Green

We compile and analyze ~200 trigonometric parallaxes and proper motions of molecular masers associated with very young high-mass stars. These measurements strongly suggest that the Milky Way is a four-arm spiral. Fitting log-periodic…

Aims: We derive the 3-D HI volume density distribution for the Galactic disk out to R = 60 kpc. Methods: Our analysis is based on parameters for the warp and rotation curve derived previously. The data are taken from the…

Astrophysics · Physics 2015-05-13 P. M. W. Kalberla , L. Dedes

The relative alignments of mid-infrared traced Galactic bubbles are compared to the orientation of the mean Galactic magnetic field in the disk. The orientations of bubbles in the northern Galactic plane were measured and are consistent…

Astrophysics of Galaxies · Physics 2015-06-11 Michael D. Pavel , Dan P. Clemens

We examine the significance of a planar arrangement in the spatial distribution of the Milky Way's globular clusters (GCs). We find that, when separated on the basis of horizontal branch morphology and metallicity, the outer-most canonical…

Astrophysics of Galaxies · Physics 2015-05-30 Stefan C. Keller , Dougal Mackey , Gary S. Da Costa

We study the formation of planes of dwarf galaxies around Milky Way (MW)-mass haloes in the EAGLE galaxy formation simulation. We focus on satellite systems similar to the one in the MW: spatially thin or with a large fraction of members…

Astrophysics of Galaxies · Physics 2019-07-08 Shi Shao , Marius Cautun , Carlos S. Frenk

This Letter presents a study of the geometry and motion of the Galactic disk using open clusters in the Gaia era. The findings suggest that the inclination of the Galactic disk increases gradually from the inner to the outer disk, with a…

Astrophysics of Galaxies · Physics 2023-08-31 Zhihong He

The WISE Catalog of Galactic HII Regions contains $\sim2000$ HII region candidates lacking ionized gas spectroscopic observations. All candidates have the characteristic HII region mid-infrared morphology of WISE $12\,\,\mu\,m$ emission…

Astrophysics of Galaxies · Physics 2015-12-09 L. D. Anderson , W. P. Armentrout , B. M. Johnstone , T. M. Bania , Dana S. Balser , Trey V. Wenger , V. Cunningham

We resolve the kinematic distance ambiguity for 266 inner Galaxy HII regions out of a sample of 291 using existing HI and 13CO sky surveys. Our sample contains all HII regions with measured radio recombination line (RRL) emission over the…

Astrophysics · Physics 2008-12-18 L. D. Anderson , T. M. Bania

We derive the synchrotron distribution in the Milky Way disk from HII region absorption observations over -40{\deg} < l < 40{\deg} at six frequencies of 76.2, 83.8, 91.5, 99.2, 106.9, and 114.6 MHz with the GaLactic and Extragalactic…

Aims: we studied the global distribution and kinematics of the extra-planar neutral gas in the Milky Way. Methods: we built 3D models for a series of Galactic HI layers, projected them for an inside view, and compared them with the…

Astrophysics of Galaxies · Physics 2015-05-20 Antonino Marasco , Filippo Fraternali

The spiral structure of the Milky Way is not yet well determined. The keys to understanding this structure are to increase the number of reliable spiral tracers and to determine their distances as accurately as possible. HII regions, giant…

Astrophysics of Galaxies · Physics 2014-10-15 L. G. Hou , J. L. Han

There is evidence in 21cm HI emission for voids several kpc in size centered approximately on the Galactic centre, both above and below the Galactic plane. These appear to map the boundaries of the Galactic nuclear wind. An analysis of HI…

Astrophysics of Galaxies · Physics 2016-08-17 Felix J. Lockman , N. M. McClure-Griffiths

A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At…

Astrophysics of Galaxies · Physics 2015-06-15 Yurii Pidopryhora , Felix J. Lockman , John M. Dickey , Michael P. Rupen

Context. Gas within a galaxy is forced to establish pressure balance against gravitational forces. The shape of an unperturbed gaseous disk can be used to constrain dark matter models. Aims. We derive the 3-D HI volume density distribution…

Astrophysics · Physics 2009-11-13 P. M. W. Kalberla , L. Dedes , J. Kerp , U. Haud

The Southern Galactic Plane Survey (SGPS) is a project to image the HI line emission and 1.4 GHz continuum in the fourth quadrant of the Milky Way at high resolution using the Australia Telescope Compact Array (ATCA) and the Parkes Radio…

The distribution of metals in the Galaxy provides important information about galaxy formation and evolution. HII regions are the most luminous objects in the Milky Way at mid-infrared to radio wavelengths and can be seen across the entire…

Astrophysics of Galaxies · Physics 2015-05-28 Dana S. Balser , Robert T. Rood , T. M. Bania , L. D. Anderson
‹ Prev 1 2 3 10 Next ›