English
Related papers

Related papers: Hydrodynamics of Cometary Compact HII Regions

200 papers

We create a photoionization model embedded in the turbulent ISM by using the state-of-the-art Messenger Monte-Carlo MAPPINGS~V code (M$^3$) in conjunction with the CMFGEN stellar atmosphere model. We show that the turbulent ISM causes the…

Astrophysics of Galaxies · Physics 2022-08-03 Yifei Jin , Lisa J. Kewley , Ralph S. Sutherland

We used a series of COBOLD hydrodynamical model atmospheres covering stellar objects from white dwarfs to red giants to derive theoretical estimates of the photometric and photocentric stellar variability in wavelength-integrated light…

Astrophysics · Physics 2007-05-23 F. Svensson , H. -G. Ludwig

We carried out 13CO J=1-0, CS, and C34S J=2-1 and J=3-2 line observations of molecular clouds associated with 16 ultracompact (UC) HII regions with extended envelopes. The molecular clouds are the ones that give birth to rich stellar…

Astrophysics · Physics 2009-11-10 Kee-Tae Kim , Bon-Chul Koo

The solar atmosphere is extremely dynamic, and many important phenomena develop on small scales that are unresolved in observations with the Helioseismic and Magnetic Imager (HMI) instrument on the Solar Dynamics Observatory (SDO). For…

Solar and Stellar Astrophysics · Physics 2015-08-06 Irina N. Kitiashvili , Sebastien Couvidat , Andreas Lagg

We present results of numerical simulations carried out with a 2D radiation hydrodynamics code in order to study the impact of massive stars on their surrounding interstellar medium. This first paper deals with the evolution of the…

Astrophysics · Physics 2009-11-10 Tim Freyer , Gerhard Hensler , Harold W. Yorke

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

We have computed a series of realistic and self-consistent models that reproduce the properties of HII galaxies. The emitted spectrum of HII galaxies is reproduced by means of the photoionization code CLOUDY, using as ionizing spectrum the…

Astrophysics · Physics 2008-10-14 M. L. Martin-Manjon , M. Molla , A. I. Diaz , R. Terlevich

Recent JWST observations of HII regions in the Central Molecular Zone have shown a highly filamentary morphology distinct from HII regions in other parts of the galaxy. We present magnetohydrodynamic (MHD) simulations of strongly magnetized…

Astrophysics of Galaxies · Physics 2026-02-25 Samuel Crowe , Yisheng Tu , Zhi-Yun Li , Jeong-Gyu Kim , John Bally

We present results of analysis of physical conditions (number density, intensity of UV field, kinetic temperature) in the cold H$_2$-bearing interstellar medium of local and high redshift galaxies. Our measurements based on the fit to the…

Astrophysics of Galaxies · Physics 2020-10-07 V. V. Klimenko , S. A. Balashev

We present multiwavelength investigation of morphology, physical-environment, stellar contents and star formation activity in the vicinity of star-forming region Sh 2-100. It is found that the Sh 2-100 region contains seven HII regions of…

Astrophysics of Galaxies · Physics 2015-05-18 M. R. Samal , A. K. Pandey , D. K. Ojha , S. K. Ghosh , V. K. Kulkarni , N. Kusakabe , M. Tamura , B. C. Bhatt , M. A. Thompson , R. Sagar

We present a set of photoionization models that reproduce simultaneously the observed optical and mid-infrared spatial distribution of the HII region NGC595 in the disk of M33 using the code CLOUDY. Both optical (PMAS-Integral Field…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Enrique Perez-Montero , Monica Relano , Jose M. Vilchez , Ana Monreal-Ibero

Observations of intergalactic neutral hydrogen can provide a wealth of information about structure and galaxy formation, potentially tracing accretion and feedback processes on Mpc scales. Below a column density of NHI ~ 10^19 cm-2, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Attila Popping , Romeel Dave , Robert Braun , Benjamin D. Oppenheimer

We present a method for simulating the evolution of HII regions driven by point sources of ionizing radiation in magnetohydrodynamic media, implemented in the three-dimensional Athena MHD code. We compare simulations using our algorithm to…

Astrophysics · Physics 2009-11-11 Mark R. Krumholz , James M. Stone , Thomas A. Gardiner

We perform three dimensional radiation hydrodynamic simulations of the structure and dynamics of radiation dominated envelopes of massive stars at the location of the iron opacity peak. One dimensional hydrostatic calculations predict an…

Solar and Stellar Astrophysics · Physics 2015-11-04 Yan-Fei Jiang , Matteo Cantiello , Lars Bildsten , Eliot Quataert , Omer Blaes

New non-linear hydrodynamic models have been constructed to simulate the radial pulsations observed in the extreme helium star V652 Her. These use a finer zoning to allow higher radial resolution than in previous simulations. Models…

Solar and Stellar Astrophysics · Physics 2021-10-13 C. Simon Jeffery , Pilar Montañés-Rodríguez , Hideyuki Saio

We use a suite of hydrodynamics simulations of the interstellar medium (ISM) within a galactic disk, which include radiative transfer, a non-equilibrium model of molecular hydrogen, and a realistic model for star formation and feedback, to…

Astrophysics of Galaxies · Physics 2024-05-07 Ava Polzin , Andrey V. Kravtsov , Vadim A. Semenov , Nickolay Y. Gnedin

The observed parameters of the young superstar cluster M82-A1 and its associated compact HII region are here shown to indicate a low heating efficiency or immediate loss, through radiative cooling, of a large fraction of the energy inserted…

Astrophysics · Physics 2009-11-13 Sergiy Silich , Guillermo Tenorio-Tagle , Casiana Munoz-Tunon

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

Aims. Massive stars impact their surrounding initiating star-formation along their photo-dissociation region. Once the HII region is formed it is unclear if and how the second generation of stars impacts its aspect and evolution. Methods.…

Astrophysics of Galaxies · Physics 2026-01-22 D. Russeil , H. Plana , P. Amram , A. Zavagno , F. Michel

Radiation pressure acting on gas and dust causes HII regions to have central densities that are lower than the density near the ionized boundary. HII regions in static equilibrium comprise a family of similarity solutions, parametrized by 3…

Astrophysics of Galaxies · Physics 2015-05-18 B. T. Draine