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Related papers: Feedback from first radiation sources: H- photodis…

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The first star formation in the universe is expected to take place within small protogalaxies, in which the gas is cooled by molecular hydrogen. However, if massive stars form within these protogalaxies, they may suppress further star…

Astrophysics · Physics 2009-10-31 Simon C. O. Glover , Peter W. J. L. Brand

H2 formation in metal-free gas occurs via the intermediate H- or H2+ ions. Destruction of these ions by photodissociation therefore serves to suppress H2 formation. In this paper, I highlight the fact that several processes that occur in…

Astrophysics · Physics 2008-11-26 S. C. O. Glover

We study the H2 photodissociation regions around OB stars in primordial gas clouds whose virial temperatures are between a few hundred and a few thousand Kelvin. In such small objects, a single O star can photodissociate a mass equal to…

Astrophysics · Physics 2009-10-31 Kazuyuki Omukai , Ryoichi Nishi

We use one-dimensional radiative transfer simulations to study the evolution of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in the primordial universe. We find a new positive feedback mechanism capable of…

Astrophysics · Physics 2009-10-31 Massimo Ricotti , Nickolay Y. Gnedin , J. Michael Shull

We consider the radiative feedback processes that operate during the formation of the first stars, including the photodissociation of H_2, Ly-alpha radiation pressure, formation and expansion of an HII region, and disk photoevaporation.…

Astrophysics · Physics 2009-11-13 Christopher F. McKee , Jonathan C. Tan

We study the effect of starlight from the first stars on the ability of other minihaloes in their neighborhood to form additional stars. The question of what the dynamical consequences were for these target minihaloes, of their exposure to…

Astrophysics · Physics 2008-11-26 Kyungjin Ahn , Paul R. Shapiro

We explore the impacts of ultraviolet (UV) radiation feedback on galaxies during the epoch of reionisation by cosmological simulations in which hydrodynamics and the transfer of the H and He ionising photons are consistently coupled.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Kenji Hasegawa , Benoit Semelin

We study the effects of the ionizing and dissociating photons produced by Pop III objects on the surrounding intergalactic medium. We find that the typical size of a H_2 photodissociated region is smaller than the mean distance between…

Astrophysics · Physics 2007-05-23 Benedetta Ciardi , Andrea Ferrara

The formation of the first galaxies is influenced by the radiative feedback from the first generations of stars. This feedback is manisfested by the heating and ionization of the gas which lies within the H II regions surrounding the first…

Astrophysics · Physics 2010-11-05 Jarrett L. Johnson , Thomas H. Greif , Volker Bromm

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

Astrophysics · Physics 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We present numerical simulations of how a 120 M$_\odot$ primordial star regulates star formation in nearby cosmological halos at $z \sim$ 20 by photoevaporation. Our models include nine-species primordial chemistry and self-consistent…

Astrophysics · Physics 2008-12-18 Daniel Whalen , Brian W. O'Shea , Joseph Smidt , Michael L. Norman

We study the effects of the ionizing and dissociating photons produced by PopIII objects on the surrounding intergalactic medium. We find that the typical size of a H_2 photodissociated region, R_d ~ 1-5 kpc, is smaller than the mean…

Astrophysics · Physics 2007-05-23 Benedetta Ciardi , Andrea Ferrara , Tom Abel

Young massive stars produce Far-UV photons which dissociate the molecular gas on the surfaces of their parent molecular clouds. Of the many dissociation products which result from this ``back-reaction'', atomic hydrogen \HI is one of the…

Astrophysics · Physics 2016-01-27 Ronald J. Allen

First, the formation of first objects driven by dark matter is revisited by high-resolution hydrodynamic simulations. It is revealed that dark matter haloes of ~10^4M_sun can produce first luminous objects with the aid of dark matter cusps.…

Astrophysics of Galaxies · Physics 2012-10-30 Masayuki Umemura , Hajime Susa , Kenji Hasegawa , Tamon Suwa , Benoit Semelin

We explore the impact of ultraviolet (UV) radiation from massive Population III (Pop III) stars of 25, 40, 80, and 120 M_sun on the subsequent Pop III star formation. In this paper, particular attention is paid to the dependence of…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Kenji Hasegawa , Masayuki Umemura , Hajime Susa

The reionization of cosmic hydrogen, left over from the big bang, increased its temperature to >~ 1.e4 K. This photo-heating resulted in an increase of the minimum mass of galaxies and hence a suppression of the cosmic star formation rate.…

Astrophysics · Physics 2009-11-11 Rennan Barkana , Abraham Loeb

The first, self-consistent calculations of the cosmological H_2 dissociating UV background produced during the epoch of reionization (EOR) by the sources of reionization are presented. Large-scale radiative transfer simulations of…

Astrophysics · Physics 2010-12-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We explore the possibility of subsequent star formation after a first star forms in a Pop III object, by focusing on the radiation hydrodynamic (RHD) feedback brought by ionizing photons as well as H2 dissociating photons. For the purpose,…

Astrophysics · Physics 2009-11-11 Hajime Susa , Masayuki Umemura

Photoheating associated with reionization suppressed star formation in low-mass galaxies. Reionization was inhomogeneous, however, affecting different regions at different times. To establish the causal connection between reionization and…

The first generation of stars (commonly known as population III) are expected to form in low-mass protogalaxies in which molecular hydrogen is the dominant coolant. Radiation from these stars will rapidly build up an extragalactic…

Astrophysics · Physics 2009-11-07 Simon C. O. Glover , Peter W. J. L. Brand
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