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Related papers: HI Shells Behind the Coalsack

200 papers

We report the detection of a ring like HI structure toward l=90.0, b=2.8 with a velocity of v_LSR=-99 km/s. This velocity implies a distance of d=13 kpc, corresponding to a Galactocentric radius of R_gal=15 kpc. The l-v_LSR diagram implies…

Astrophysics · Physics 2009-11-07 Bulent Uyaniker , Roland Kothes

HI 21 cm observations with the NRAO 140 Foot telescope have revealed a giant HI cloud (G28.17+0.05) in the Galactic plane that has unusual properties. The cloud is 150 pc in diameter, is at a distance of 5 kpc, and contains as much as…

Astrophysics · Physics 2007-05-23 Anthony Minter , Felix J. Lockman

We present multi-scale and multi-wavelength observations of the Galactic HII region S305, which is excited by massive O8.5V and O9.5V stars. Infrared images reveal an extended sphere-like shell (extension ~7.5 pc; at T_d = 17.5-27 K)…

Astrophysics of Galaxies · Physics 2020-08-12 L. K. Dewangan , Saurabh Sharma , Rakesh Pandey , S. del Palacio , D. K. Ojha , P. Benaglia , T. Baug , S. R. Das

Recent advances in identifying giant molecular filaments in galactic surveys allow us to study the interstellar material and its dense, potentially star forming phase on scales comparable to resolved extragalactic clouds. Two large…

Astrophysics of Galaxies · Physics 2024-03-29 O. Feher , S. E. Ragan , F. D. Priestley , P. C. Clark , T. J. T. Moore

Large HI shells, with diameters of hundreds of pc and expansion velocities of 10-20kms-1 are well observed features of local gas rich galaxies. These shells could well be predicted as a result of the impact of OB associations on the ISM,…

Astrophysics · Physics 2009-11-13 M. Relano , J. E. Beckman , O. Daigle , C. Carignan

A population of discrete HI clouds in the halo of the inner Galaxy has been discovered in 21cm observations made with the Green Bank Telescope. The halo clouds are seen up to 1.5 kpc from the Galactic plane at many longitudes. Their…

Astrophysics · Physics 2009-11-07 Felix J. Lockman

Two mysterious unresolved HI structures at velocities of +12 and -6 km/s were discovered in high resolution 21-cm survey data in the direction of a faint white dwarf star. Examination of the HI morphology in this area of sky shows that the…

Astrophysics of Galaxies · Physics 2026-02-10 Gerrit L. Verschuur

Here we report the discovery with the Giant Metrewave Radio Telescope of an extremely large ($\sim$115 kpc in diameter) HI ring off-centered from a massive quenched galaxy, AGC 203001. This ring does not have any bright extended optical…

An isolated HI cloud with peculiar properties has recently been discovered by Dedes, Dedes, & Kalberla (2008, A&A, 491, L45) with the 300-m Arecibo telescope, and subsequently imaged with the VLA. It has an angular size of ~6', and the HI…

Astrophysics of Galaxies · Physics 2014-11-18 Y. Libert , E. Gerard , T. Le Bertre , L. D. Matthews , C. Thum , J. M. Winters

We present a map of the spiral structure of the Galaxy, as traced by molecular CS emission associated with IRAS sources which are believed to be compact HII regions. The CS line velocities are used to determine the kinematic distances of…

Astrophysics of Galaxies · Physics 2015-05-20 J. R. D. Lepine , A. Roman-Lopes , Zulema Abraham , T. C. Junqueira , Yu. N. Mishurov

We have analyzed the archival data of FUV observations for the region of GSH 006-15+7, a large shell-like structure discovered by Moss et al. (2012) from the H I velocity maps. FUV emission is seen to be enhanced in the lower supershell…

Astrophysics of Galaxies · Physics 2015-05-25 Young-Soo Jo , Kyoung-Wook Min , Kwang-Il Seon

Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), we detect a giant HI filamentary structure in the sky region of 307$.\!\!^{\circ}$7 $<$ $\alpha$ $<$ 311$.\!\!^{\circ}$0 and 40$.\!\!^{\circ}$9 $<$ $\delta$ $<$…

Astrophysics of Galaxies · Physics 2021-09-01 Chong Li , Keping Qiu , Bo Hu , Yue Cao

The first detailed VLA mapping of the neutral hydrogen distribution in the isolated, edge-on spiral galaxy NGC 3044 is presented. Physical parameters determined for this galaxy are typical for galaxies of its morphological class (SBc). We…

Astrophysics · Physics 2009-10-30 Siow-Wang Lee , Judith A. Irwin

We present new radio recombination line observations of the previously unstudied HII region CTB 102. Line parameters are extracted and physical parameters describing the gas are calculated. We estimate the distance to CTB 102 to be 4.3 kpc.…

Astrophysics of Galaxies · Physics 2009-07-22 K. Arvidsson , C. R. Kerton , T. Foster

We report an observational study of the Galactic HII region Sh 2-305/S305 using the [CII] 158 $\mu$m line data, which are used to examine the gas dynamics and structure of photodissociation regions. The integrated [CII] emission map at…

Astrophysics of Galaxies · Physics 2021-12-08 N. K. Bhadari , L. K. Dewangan , P. M. Zemlyanukha , D. K. Ojha , I. I. Zinchenko , Saurabh Sharma

We present a 21cm line HI self-absorption (HISA) survey of cold atomic gas within Galactic longitudes 75 to 146 degrees and latitudes -3 to +5 degrees. We identify HISA as spatially and spectrally confined dark HI features and extract it…

We present new high resolution neutral hydrogen (H I) images of the Galactic supershell GSH 242-03+37. These data were obtained with the Parkes Radiotelescope as part of the Galactic All-Sky Survey (GASS). GSH 242-03+37 is one of the…

We analyse the all-sky Leiden/Argentina/Bonn HI survey, where we identify shells belonging to the Milky Way. We used an identification method based on the search of continuous regions of a low brightness temperature that are compatible with…

Astrophysics of Galaxies · Physics 2015-06-12 S. Ehlerova , J. Palous

We present the detection of an enormous disc of cool neutral hydrogen (HI) gas surrounding the S0 galaxy NGC 612, which hosts one of the nearest powerful radio sources (PKS 0131-36). Using the Australia Telescope Compact Array, we detect…

We study the properties of HI gas in the outer regions (~2r_25) of a spiral galaxy, UGC 00439 (z = 0.01769), using HI 21-cm absorption towards different components of an extended background radio source, J0041$-$0043 (z = 1.679). The radio…

Astrophysics of Galaxies · Physics 2016-01-20 Rajeshwari Dutta , Neeraj Gupta , Raghunathan Srianand , John O'Meara