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Related papers: Finding Distant Galactic HII Regions

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Cosmological applications of HII galaxies (HIIGx) and giant extragalactic HII regions (GEHR) to construct the Hubble diagram at higher redshifts require knowledge of the "$L$--$\sigma$" relation of the standard candles used. In this paper,…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-29 Yan Wu , Shuo Cao , Jia Zhang , Tonghua Liu , Yuting Liu , Shuaibo Geng , Yujie Lian

Motivated by recent discoveries of nearby galaxies in the Zone of Avoidance, we conducted a pilot study of galaxy candidates at low Galactic latitude, near Galactic longitude $l \sim 135^0$, where the Supergalactic Plane is crossed by the…

Astrophysics · Physics 2009-10-30 O. Lahav , N. Brosch , E. Goldberg , G. K. T. Hau , R. C. Kraan-Korteweg , A. J. Loan

As part of our programme to map the large-scale distribution of galaxies behind the southern Milky Way, we observed 314 optically-selected, partially-obscured galaxies in the Zone of Avoidance (ZOA) in the Crux and Great Attractor (GA)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Anja C. Schroeder , Renee C. Kraan-Korteweg , Patricia A. Henning

Galactic HI (neutral hydrogen) shells are central to our understanding of the interstellar medium (ISM), which plays a key role in the development and evolution of galaxies, including our own. Several models involving supernovae and stellar…

Astrophysics of Galaxies · Physics 2016-06-30 Shauna M. Sallmen , Eric J. Korpela , Brooke Bellehumeur , Elizabeth M. Tennyson , Kurt Grunwald , Cheuk Man Lo

We present here our shape analysis method for a sample of 76 Galactic HII regions from MAGPIS 1.4 GHz data. The main goal is to determine whether physical properties and initial conditions of massive star cluster formation is linked to the…

Astrophysics of Galaxies · Physics 2018-05-02 Justyn Campbell-White , Dirk Froebrich , Alfred Kume

The existence of density-bounded HII regions in spiral galaxies is supported by means of a spectral indicator based on the intensity of the [OI]6300A forbidden line. A grid of photoionization models providing spectral information of…

Astrophysics · Physics 2009-11-07 J. Iglesias-Paramo , C. Munoz-Tunon

This paper presents infrared spectra taken with the newly commissioned NIRSPEC spectrograph on the Keck Telescope of the High Redshift Radio Galaxy MRC 2025-218 (z=2.630) and an extremely red galaxy (R-K > 6 mag) 9'' away. These…

The Green Bank Telescope H II Region Discovery Survey (GBT HRDS) found hundreds of previously unknown Galactic regions of massive star formation by detecting hydrogen radio recombination line (RRL) emission from candidate H II region…

Astrophysics of Galaxies · Physics 2015-06-12 Trey V. Wenger , T. M. Bania , Dana S. Balser , L. D. Anderson

We describe HI observations of a 4 x 4 degrees field in the Milky Way centered on l=61 deg, b=0 deg made by the Effelsberg radiotelescope. The field contains one previously identified HI supershell, GS061+00+51 (Heiles, 1979); apart from it…

Astrophysics · Physics 2009-11-06 S. Ehlerova , J. Palous , W. K. Huchtmeier

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

The Very Small Array (VSA) has been used to survey the l = 27 to 46 deg, |b|<4 deg region of the Galactic plane at a resolution of 13 arcmin. The survey consists of 44 pointings of the VSA, each with a r.m.s. sensitivity of ~90 mJy/beam.…

As part of a systematic study that we are performing with the aim to increase the observational evidence of triggered star formation in the surroundings of HII regions, we analyze the ISM around the HII region G35.673-00.847, a poorly…

Astrophysics of Galaxies · Physics 2015-05-20 S. Paron , A. Petriella , M. E. Ortega

As part of our program to map the large-scale distribution of galaxies behind the Milky Way, we used the Parkes 210 ft (64 m) radio telescope for pointed HI observations of a sample of low surface-brightness (due to heavy obscuration)…

Astrophysics · Physics 2009-11-07 Renee C. Kraan-Korteweg , Patricia A. Henning , Anja C. Schroeder

We study the presence of low intensity high velocity components, which we have termed wing features in the integrated Halpha emission line profiles of the HII region populations of the spiral barred galaxies NGC 1530, NGC 3359 and NGC 6951.…

Astrophysics · Physics 2009-11-10 M. Relano , J. E. Beckman

We present a pilot survey of 21 lines of sight towards UCHII regions in the H2CO 1-1 (6cm) and 2-2 (2cm) transitions, using the H2CO centimeter lines as a molecular gas densitometer. Using Arecibo and Green Bank beam-matched observations,…

Astrophysics of Galaxies · Physics 2011-07-27 Adam Ginsburg , Jeremy Darling , Cara Battersby , Ben Zeiger , John Bally

The low column density gas at the outskirts of galaxies as traced by the 21 cm hydrogen line emission (HI) represents the interface between galaxies and the intergalactic medium, i.e., where galaxies are believed to get their supply of gas…

Astrophysics of Galaxies · Physics 2018-05-23 Roger Ianjamasimanana , Fabian Walter , W. J. G. de Blok , George H. Heald , Elias Brinks

We report the discovery of two new large HI shells in the direction of the Coalsack nebula. Both shells were observed with the Parkes Radio Telescope as part of the Southern Galactic Plane Survey. The largest shell, GSH 304-00-12, is at a…

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

To investigate the process of star formation triggered by the expansion of an HII region, we present a multi-wavelength analysis of the Galactic HII region RCW 120 and its surroundings. The collect and collapse model predicts that the layer…

We present a first study based on the analysis of the DEep Spectra of Ionized REgions Database (DESIRED). This is a compilation of 190 high signal-to-noise ratio optical spectra of HII regions and other photoionized nebulae, mostly observed…

We present some results of an ongoing project devoted to reassess the radial abundance gradients in the disc of the MilkyWay based on deep spectroscopy of Hii regions. The data have been taken with large aperture telescopes, mainly with the…

Astrophysics of Galaxies · Physics 2019-05-27 C. Esteban , J. García-Rojas , K. Z. Arellano-Córdova , J. E. Méndez-Delgado