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Related papers: HI shells in the outer Milky Way

200 papers

We produce a detailed map of the perturbed surface density of neutral hydrogen in the outer Milky Way disk demonstrating that the Galaxy is a non-axisymmetric multi-armed spiral. Spiral structure in the southern half of the Galaxy can be…

Astrophysics · Physics 2009-11-11 E. S. Levine , Leo Blitz , Carl Heiles

We present a panoramic map of the entire Milky Way halo north of dec~-30 degrees (~30,000 deg^2), constructed by applying the matched-filter technique to the Pan-STARRS1 3Pi Survey dataset. Using single-epoch photometry reaching to g~22, we…

Using atomic hydrogen (HI) data from the VLA Galactic Plane Survey we measure the HI terminal velocity as a function of longitude for the first quadrant of the Milky Way. We use these data, together with our previous work on the fourth…

Astrophysics of Galaxies · Physics 2016-11-09 N. M. McClure-Griffiths , J. M. Dickey

Currently only a small number of Milky Way (MW) stars are known to exist beyond 100 kpc from the Galactic center. Though the distribution of these stars in the outer halo is believed to be sparse, they can provide evidence of more recent…

Astrophysics of Galaxies · Physics 2017-08-02 Robyn E. Sanderson , Amy Secunda , Kathryn V. Johnston , John J. Bochanski

Observations of HI published in 1957 by Westerhout and Schmidt were presented as showing a global face-on view of spiral structure in the Milky Way. Since then many studies have attempted to improve on the early map, perhaps presupposing…

Astrophysics of Galaxies · Physics 2025-11-04 Dana S. Balser , W. B. Burton

Filaments are a ubiquitous morphological feature of the molecular interstellar medium and are identified as sites of star formation. In recent years, more than 100 large-scale filaments (with a length $>10$\,pc) have been observed in the…

Using the Leiden/Dwingeloo Survey (Hartmann & Burton 1997) of the Galactic sky north of declination -30 degrees as the principal component of a composite data cube, the structure of the warped HI layer of the outer Galaxy was displayed by…

Astrophysics · Physics 2007-05-23 Tom Voskes , W. Butler Burton

The spiral structure of the Milky Way is not conclusive, even for the disc regions in the solar neighbourhood. Especially, the arm-like structures uncovered from the over-density maps of evolved stars are inconsistent with the commonly…

Astrophysics of Galaxies · Physics 2025-04-09 X. J. Shen , L. G. Hou , H. L. Liu , X. Y. Gao

The HI Parkes Zone of Avoidance Survey is a 21 cm blind search with the multibeam receiver on the 64-m radiotelescope, looking for galaxies hidden behind the southern Milky Way. The first, shallow (15 mJy rms) phase of the survey has…

Astrophysics · Physics 2015-06-24 P. A. Henning , L. Staveley-Smith , R. C. Kraan-Korteweg , E. M. Sadler

We present the structure of the Milky Way stellar halo beyond Galactocentric distances of $r = 50$ kpc traced by blue horizontal-branch (BHB) stars, which are extracted from the survey data in the Hyper Suprime-Cam Subaru Strategic Program…

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

The environmental density of galaxies within the cosmic web constrains their 3D locations in filaments, voids, groups, and clusters. It traces the distribution of baryons and the influence of dark-matter halos on galaxy evolution, and helps…

We report on the global structure of the Milky Way (MW) stellar halo up to its outer boundary based on the analysis of blue-horizontal branch stars (BHBs). These halo tracers are extracted from the $(g,r,i,z)$ band multi-photometry in the…

Using HIPASS data, we have searched for HI in a ~25x25 sq.deg. region centred on the Fornax cluster. Within a velocity search range of 300 - 3700 km/s and a lower flux limit of ~40 mJy, 110 galaxies with HI emission were detected, one of…

The ubiquity of filamentary structure at various scales through out the Galaxy has triggered a renewed interest in their formation, evolution, and role in star formation. The largest filaments can reach up to Galactic scale as part of the…

Astrophysics of Galaxies · Physics 2015-07-09 Ke Wang , Leonardo Testi , Adam Ginsburg , C. Malcolm Walmsley , Sergio Molinari , Eugenio Schisano

The Milky Way's million degree gaseous halo contains a considerable amount of mass that, depending on its structural properties, can be a significant mass component. In order to analyze the structure of the Galactic halo, we use XMM-Newton…

Astrophysics of Galaxies · Physics 2015-06-15 Matthew Miller , Joel Bregman

In a framework where galaxies form hierarchically, extended stellar haloes are predicted to be an ubiquitous feature around Milky Way-like galaxies and to consist mainly of the shredded stellar component of smaller galactic systems. The…

Astrophysics of Galaxies · Physics 2017-12-20 G. Battaglia , P. North , P. Jablonka , M. Shetrone , D. Minniti , M. Díaz , E. Starkenburg , M. Savoy

In order to constrain the evolutionary history of the Milky Way, we hunt for faint RR Lyrae stars (RRLs) using Dark Energy Camera data from the High cadence Transient Survey (HiTS) and the Halo Outskirts With Variable Stars (HOWVAST)…

We investigate the structure of the Milky Way's stellar halo within 70 kpc of the Sun using a wide-field photometric catalog obtained from the Hyper Suprime-Cam (HSC) Subaru Strategic Program (HSC-SSP). We employ a large sample of…

Astrophysics of Galaxies · Physics 2026-04-14 Yoshihisa Suzuki , Masashi Chiba , Rosemary F. G. Wyse , Shunichi Horigome

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