# Achievements & Publications

### A Spectrophotometric Method to Determine the Inclination of Class I Objects

#### Nakazato, Takeshi,   Nakamoto, Taishi,   Umemura, Masayuki

A new method that enables us to estimate the inclination of Class I young stellar objects is proposed. Since Class I objects are not spherically symmetric, it is likely that the observed feature is sensitive to the inclination of the system. Thus, we construct a protostar model by carefully treating...

### Protoquasars: Physical States and Observable Properties

#### Kawakatu, Nozomu,   Umemura, Masayuki,   Mori, Masao

Based on the radiation hydrodynamic model for black hole (BH) growth and incorporating the chemical evolution of the early-type host galaxy, we construct the coevolution model of the quasar (QSO) BH and host galaxy. As a result, it is found that after a galactic wind epoch, the luminosity is shifted...

### A Search for Ly\ensuremathα Emitters at Redshift 3.7

#### Fujita, Shinobu S.,   Ajiki, Masaru,   Shioya, Yasuhiro,   Nagao, Tohru,   Murayama, Takashi,   Taniguchi, Yoshiaki

We present the results of a survey for emission-line objects, based on optical intermediate-band (\ensuremathłambda$_c$=5736 ̊A and \ensuremathΔ\ensuremathłambda=280 \Å) and broadband (B, V, R, and i') observations of the Subaru/XMM-Newton Deep Field with the 8.2 m Subaru telescope and the Subaru Prime Focus Camera (Suprime-Cam). All the data were obtained...

### Does the Slim-Disk Model Correctly Consider Photon-trapping Effects?

#### Ohsuga, Ken,   Mineshige, Shin,   Mori, Masao,   Umemura, Masayuki

We investigate the photon-trapping effects in the supercritical black hole accretion flows by solving radiation transfer as well as the energy equations of radiation and gas. It is found that the slim-disk model generally overestimates the luminosity of the disk around the Eddington luminosity (L$_E$) and is not accurate in...

### The Stellar Initial Mass Function in Primordial Galaxies

#### Nakamura, Fumitaka,   Umemura, Masayuki

In the context of star formation through fragmentation of an extremely metal deficient protogalactic cloud, the gravitational collapse of filamentary gas clouds is explored with one-dimensional numerical hydrodynamics coupled with nonequilibrium chemistry of H$_2$ and HD. It is found that the cloud evolution is governed mainly by the initial central...

### A Spectrophotometric Method to Determine the Inclination of Class I Objects

#### Nakazato, Takeshi,   Nakamoto, Taishi,   Umemura, Masayuki

A new method that enables us to estimate the inclination of Class I young stellar objects is proposed. Since Class I objects are not spherically symmetric, it is likely that the observed feature is sensitive to the inclination of the system. Thus, we construct a protostar model by carefully treating...

January 2003   The Astrophysical Journal

### Protoquasars: Physical States and Observable Properties

#### Kawakatu, Nozomu,   Umemura, Masayuki,   Mori, Masao

Based on the radiation hydrodynamic model for black hole (BH) growth and incorporating the chemical evolution of the early-type host galaxy, we construct the coevolution model of the quasar (QSO) BH and host galaxy. As a result, it is found that after a galactic wind epoch, the luminosity is shifted...

January 2003   The Astrophysical Journal

### A Search for Ly\ensuremathα Emitters at Redshift 3.7

#### Fujita, Shinobu S.,   Ajiki, Masaru,   Shioya, Yasuhiro,   Nagao, Tohru,   Murayama, Takashi,   Taniguchi, Yoshiaki

We present the results of a survey for emission-line objects, based on optical intermediate-band (\ensuremathłambda$_c$=5736 ̊A and \ensuremathΔ\ensuremathłambda=280 \Å) and broadband (B, V, R, and i') observations of the Subaru/XMM-Newton Deep Field with the 8.2 m Subaru telescope and the Subaru Prime Focus Camera (Suprime-Cam). All the data were obtained...

January 2003   The Astronomical Journal

### Does the Slim-Disk Model Correctly Consider Photon-trapping Effects?

#### Ohsuga, Ken,   Mineshige, Shin,   Mori, Masao,   Umemura, Masayuki

We investigate the photon-trapping effects in the supercritical black hole accretion flows by solving radiation transfer as well as the energy equations of radiation and gas. It is found that the slim-disk model generally overestimates the luminosity of the disk around the Eddington luminosity (L$_E$) and is not accurate in...

July 2002   The Astrophysical Journal

### The Stellar Initial Mass Function in Primordial Galaxies

#### Nakamura, Fumitaka,   Umemura, Masayuki

In the context of star formation through fragmentation of an extremely metal deficient protogalactic cloud, the gravitational collapse of filamentary gas clouds is explored with one-dimensional numerical hydrodynamics coupled with nonequilibrium chemistry of H$_2$ and HD. It is found that the cloud evolution is governed mainly by the initial central...

April 2002   The Astrophysical Journal