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Related papers: Hydrodynamical models of cometary HII regions

200 papers

We have made a new survey of emission-line stars in the W5E HII region to investigate the population of PMS stars near the OB stars by using the Wide Field Grism Spectrograph 2 (WFGS2). A total of 139 H-alpha emission stars were detected…

Astrophysics · Physics 2015-05-13 Makoto Nakano , Koji Sugitani , Takahiro Niwa , Yoichi Itoh , Makoto Watanabe

We provide an extensive set of theoretical spectral energy distributions of massive stars derived from our "combined stellar structure and atmosphere models". The calculations covering the entire main sequence evolution for initial masses…

Astrophysics · Physics 2016-08-30 Daniel Schaerer , Alex de Koter

Large HII regions, with angular dimensions exceeding 10 pc, usually enclose numerous massive O-stars. Stellar winds from such stars are expected to play a sizeable role in the dynamical, morphological and chemical evolution of the targeted…

Astrophysics of Galaxies · Physics 2015-06-03 Dominic Lagrois , Gilles Joncas , Laurent Drissen

We present high angular and spectral resolution HI 21~cm line observations toward the cometary-shaped compact HII region G213.880-11.837 in the GGD~14 complex.The kinematics and morphology of the photodissociated region, traced by the HI…

We investigate the physical and chemical processes at work during the formation of a massive protostar based on the observation of water in an outflow from a very young object previously detected in H2 and SiO in the IRAS 17233-3606 region.…

Astrophysics of Galaxies · Physics 2014-05-08 S. Leurini , A. Gusdorf , F. Wyrowski , C. Codella , T. Csengeri , F. van der Tak , H. Beuther , D. R. Flower , C. Comito , P. Schilke

Much difficulty has so far prevented the emergence of a consistent scenario for the origin of Type Ib and Ic supernovae (SNe). Here, we follow a heuristic approach by examining the fate of helium stars in the mass range 4 to 12Msun, which…

Solar and Stellar Astrophysics · Physics 2020-10-14 Luc Dessart , Sung-Chul Yoon , David R. Aguilera-Dena , Norbert Langer

We present new results of a spectroscopic survey of circumstellar HI in the direction of evolved stars made with the Nancay Radiotelescope. The HI line at 21 cm has been detected in the circumstellar shells of a variety of evolved stars:…

Astrophysics · Physics 2018-05-02 Gerard , Le Bertre

An investigation of dust emission associated with a large sample of HII regions has been carried out. Stacked results from this sample suggest that each HII region is at or near the center of a cluster of dense cores, that extends far…

Astrophysics of Galaxies · Physics 2019-11-06 George Bobotsis , Michel Fich

We report multifrequency radio continuum and hydrogen radio recombination line observations of HII regions near l=24.8d b=0.1d using the Giant Metrewave Radio Telescope (GMRT) at 1.28 GHz (n=172), 0.61 GHz (n=220) and the Very Large Array…

Astrophysics · Physics 2011-08-02 N. G. Kantharia , W. M. Goss , D. Anish Roshi , Niruj R. Mohan , Francois Viallefond

We present 1.3 and 3.6cm radio continuum images and a HCO+ spectrum of the massive star forming region G75.78+0.34 obtained with the Very Large Array (VLA) and with the Berkley Illinois Maryland Association (BIMA) interferometer. Three…

Astrophysics of Galaxies · Physics 2015-06-18 Rogemar A. Riffel , Everton Ludke

We present HI data cubes of four low-luminosity early-type galaxies which are currently forming stars. These galaxies have absolute magnitudes in the range M_B=-17.9 to -19.9 (H_o=50 km/s/Mpc). Their HI masses range between a few times 10^8…

Astrophysics · Physics 2016-08-30 E. Sadler , T. Oosterloo , R. Morganti

A significant number of S0 galaxies with a detectable ISM show some level of on-going massive-star formation activity in the form of visible HII regions. A rich ISM, however, does not guarantee star formation: a similar number of gas-rich…

Astrophysics · Physics 2007-05-23 Richard W. Pogge , Paul B. Eskridge

The southern Galactic high mass star-forming region, G351.6-1.3, is a HII region-molecular cloud complex with a luminosity of 2.0 x 10^5 L_sun, located at a distance of 2.4 kpc. In this paper, we focus on the investigation of the associated…

Astrophysics of Galaxies · Physics 2015-06-19 S. Vig , S. K. Ghosh , D. K. Ojha , R. P. Verma , M. Tamura

In general, HII regions do not show clear signs of self-enrichment in products from massive stars (M > 8 M_sun). In order to explore why, I modeled the contamination with Wolf-Rayet star ejecta of metal-poor (Z=0.001) HII regions, ionised…

Astrophysics of Galaxies · Physics 2009-11-13 Aida Wofford

We investigated six H II regions with infrared, bright rimmed bubble or cometary morphology, in search of quantitative evidence for triggered star formation, both collect and collapse and radiatively driven implosion. We identified and…

We present a model for the interstellar medium of NGC4214 with the objective to probe the physical conditions in the two main star-forming regions and their connection with the star formation activity of the galaxy. We used the spectral…

Astrophysics of Galaxies · Physics 2015-08-19 A. Dimaratos , D. Cormier , F. Bigiel , S. C. Madden

The Galactic HII region G353.2+0.9 is excited by the massive open cluster Pismis-24. By analyzing (sub-)mm molecular-line and -continuum we study the detailed morphology of the gas and dust, as well as their physical parameters and their…

Astrophysics of Galaxies · Physics 2015-06-03 A. Giannetti , J. Brand , F. Massi , A. Tieftrunk , M. T. Beltran

We report on a study of the high-mass star formation in the the HII region W28A2 by investigating the molecular clouds extended over ~5-10 pc from the exciting stars using the 12CO and 13CO (J=1-0) and 12CO (J=2-1) data taken by the NANTEN2…

We investigate the kinematic properties of Galactic HII regions using radio recombination line (RRL) emission detected by the Australia Telescope Compact Array (ATCA) at 4-10 GHz and the Jansky Very Large Array (VLA) at 8-10 GHz. Our HII…

Astrophysics of Galaxies · Physics 2021-11-24 Dana S. Balser , Trey V. Wenger , L. D. Anderson , W. P. Armentrout , T. M. Bania , J. R. Dawson , John M. Dickey

We report the results obtained from a multi-wavelength study of the HII region, G18.148$-$0.283, using the upgraded Giant Metre-wave Radio Telescope (uGMRT) at 1350 MHz along with other archival data. In addition to the radio continuum…

Astrophysics of Galaxies · Physics 2022-01-28 Jyotirmoy Dey , Jagadheep D. Pandian , Dharam Vir Lal