研究成果・発表論文

The effects of radiative transfer on the reionization of an inhomogeneous universe

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Nakamoto, Taishi,   Umemura, Masayuki,   Susa, Hajime

Assuming simple dynamics for the growth of density fluctuations, we implement six-dimensional (6D) radiative transfer calculations to elucidate the effects of photon propagation during the reionization of an inhomogeneous universe. The ionizing sourc...

Radiation-hydrodynamical collapse of pre-galactic clouds in the ultraviolet background

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Kitayama, T.,   Tajiri, Y.,   Umemura, M.,   Susa, H.,   Ikeuchi, S.

To explain the effects of the ultraviolet (UV) background radiation on the collapse of pre-galactic clouds, we implement a radiation- hydrodynamical calculation, combining one-dimensional spherical hydrodynamics with an accurate treatment of the radi...

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The effects of radiative transfer on the reionization of an inhomogeneous universe

Nakamoto, Taishi,   Umemura, Masayuki,   Susa, Hajime

Assuming simple dynamics for the growth of density fluctuations, we implement six-dimensional (6D) radiative transfer calculations to elucidate the effects of photon propagation during the reionization of an inhomogeneous universe. The ionizing sourc...

平成13年 3月   Monthly Notices of the Royal Astronomical Society
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On the Initial Mass Function of Population III Stars

Nakamura, Fumitaka,   Umemura, Masayuki

The collapse and fragmentation of filamentary primordial gas clouds are explored using one- and two-dimensional hydrodynamical simulations coupled with the nonequilibrium processes of hydrogen molecule formation. The cloud evolution is computed from ...

平成13年 2月   The Astrophysical Journal
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Ultraviolet-background-induced bifurcation of galactic morphology

Susa, Hajime,   Umemura, Masayuki

Based upon a novel paradigm of galaxy formation under the influence of an ultraviolet background, the evolutionary bifurcation of pre- galactic clouds is compared with observations of elliptical and spiral galaxies. The theory predicts that the dicho...

平成12年 8月   Monthly Notices of the Royal Astronomical Society
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Formation of Primordial Galaxies under Ultraviolet Background Radiation

Susa, Hajime,   Umemura, Masayuki

The pancake collapse of pregalactic clouds under UV background radiation is explored with a one-dimensional sheet model. Here, attention is concentrated on elucidating the basic physics on the thermal evolution of pregalactic clouds exposed to diffus...

平成12年 7月   The Astrophysical Journal
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Radiation-hydrodynamical collapse of pre-galactic clouds in the ultraviolet background

Kitayama, T.,   Tajiri, Y.,   Umemura, M.,   Susa, H.,   Ikeuchi, S.

To explain the effects of the ultraviolet (UV) background radiation on the collapse of pre-galactic clouds, we implement a radiation- hydrodynamical calculation, combining one-dimensional spherical hydrodynamics with an accurate treatment of the radi...

平成12年 6月   Monthly Notices of the Royal Astronomical Society