The Nature of Optically Dull Active Galactic Nuclei in COSMOS (2009)
Trump, Jonathan R., Impey, Chris D., Taniguchi, Yoshi, Brusa, Marcella, Civano, Francesca, Elvis, Martin, ...
We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull active galactic nuclei (AGNs) in the COSMOS field. These objects exhibit the X-ray luminosity of an AGN but lack broad...
The Nature of Optically Dull Active Galactic Nuclei in COSMOS (2009)
Trump, Jonathan R., Impey, Chris D., Taniguchi, Yoshi, Brusa, Marcella, Civano, Francesca, Elvis, Martin, ...
We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull AGNs in the COSMOS field. These objects exhibit the X-ray luminosity of an active galactic nucleus (AGN) but lack broad...
Nakajima, Aki, Shioya, Yasuhiro, Nagao, Tohru, Saito, Tomoki, Murayama, Takashi, Sasaki, Shunji S., ...
We present our analysis on the clustering properties of star-forming galaxies selected by narrow-band excesses in the Subaru Deep Field. Specifically we focus on Halpha emitting galaxies at z = 0.24...
Star-Forming Galaxies at z=0.24 in the Subaru Deep Field and the Sloan Digital Sky Survey (2008)
Morioka, Taichi, Nakajima, Aki, Taniguchi, Yoshiaki, Shioya, Yasuhiro, Murayama, Takashi, Sasaki, Shunji S.
We make a search for Halpha emitting galaxies at z=0.24 in the Subaru Deep Field (SDF) using the archival data set obtained with the Subaru Telescope. We carefully select Halpha emitters in the...
Nagao, Tohru, Sasaki, Shunji, Maiolino, Roberto, Grady, Celestine, Kashikawa, Nobunari, Ly, Chun, ...
We present a new photometric search for high-z galaxies hosting Population III (PopIII) stars based on deep intermediate-band imaging observations obtained in the Subaru Deep Field (SDF), by using...
Nagao, Tohru, Murayama, Takashi, Maiolino, Roberto, Marconi, Alessandro, Kashikawa, Nobunari, Ajiki, Masaru, ...
We report new follow-up spectroscopy of i-dropout galaxies with an NB921-band depression found in the Subaru Deep Field. The NB921-depressed i-dropout selection method is expected to select galaxies...
The HI content of star-forming galaxies at z = 0.24 (2007)
Lah, Philip, Chengalur, Jayaram N., Briggs, Frank H., Colless, Matthew, De Propris, Roberto, Pracy, Michael B., ...
We use observations from the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of star-forming galaxies at z = 0.24 (i.e. a look-backtime of ~3 Gyr). The sample of...
Environmental Effects on Gaseous Disks of the Virgo Spiral Galaxies (2006)
Nakanishi, Hiroyuki, Kuno, Nario, Sofue, Yoshiaki, Sato, Naoko, Nakai, Naomasa, Shioya, Yasuhiro, ...
We found high molecular fractions ($f_{\rm mol}$; ratio of the molecular to total gas surface densities) in three of five Virgo spiral galaxies in spite of their low total gas column density, based...
Dissipative transformation of non-nucleated dwarf galaxies into nucleated systems (2006)
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent photometric observations by the {\it Hubble Space Telescope (HST)} have revealed the physical properties of stellar galactic nuclei in nucleated dwarf galaxies in the Virgo cluster of...
Ajiki, Masaru, Taniguchi, Yoshiaki, Murayama, Takashi, Shioya, Yasuhiro, Nagao, Tohru, Sasaki, Shunji S., ...
Recently, Zheng et al. (2005) found evidence for an overdensity of galaxies around a radio-loud quasar, SDSS J0836+0054, at z=5.8 (a five arcmin$^2$ region). We have examined our deep optical imaging...
Dissipative transformation of nonnucleated dwarf galaxies into nucleated systems (2006)
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent photometric observations by the Hubble Space Telescope have revealed the physical properties of stellar galactic nuclei in nucleated dwarf galaxies in the Virgo cluster of galaxies. In order...
Dissipative transformation of nonnucleated dwarf galaxies into nucleated systems (2006)
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent photometric observations by the Hubble Space Telescope have revealed the physical properties of stellar galactic nuclei in nucleated dwarf galaxies in the Virgo cluster of galaxies. In order...
Ajiki, Masaru, Shioya, Yasuhiro, Taniguchi, Yoshiaki, Murayama, Takashi, Nagao, Tohru, Sasaki, Shunji S., ...
We discuss observational properties of strong emission-line galaxies at low redshift found by our deep imaging survey for high-redshift Ly alpha emitters. In our surveys, we used the narrowband...
An Intermediate-band imaging survey for high-redshift Lyman Alpha Emitters: The Mahoroba-11 (2005)
Yamada, Sanae F., Sasaki, Shunji S., Sumiya, Ryoko, Umeda, Kazuyoshi, Shioya, Yasuhiro, Ajiki, Masaru, ...
We present results of our intermediate-band optical imaging survey for high-$z$ Ly$\alpha$ emitters (LAEs) using the prime focus camera, Suprime-Cam, on the 8.2m Subaru Telescope. In our survey, we...
Narrow-Band Survey of the GOODS Fields: Search for Lyman-Alpha Emitters at z = 5.7 (2005)
Ajiki, Masaru, Mobasher, Bahram, Taniguchi, Yoshiaki, Shioya, Yasuhiro, Nagao, Tohru, Murayama, Takashi, ...
We present results from optical narrow-band lambda_c = 8150A ~ and Delta lambda = 120A) observations of the Great Observatories Origins Deep Survey (GOODS) fields, using Suprime-Cam on the Subaru...
Nagao, Tohru, Motohara, Kentaro, Maiolino, Roberto, Marconi, Alessandro, Taniguchi, Yoshiaki, Aoki, Kentaro, ...
We present a very deep near-infrared spectroscopic observation of a strong Ly_alpha emitter at z=6.33, SDF J132440.6+273607, which we used to search for HeII 1640. This emission line is expected if...
A survey of NB921 dropouts in the Subaru Deep Field (2005)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Ajiki, Masaru, Nagao, Tohru, Murayama, Takashi, Sasaki, Shunji S., ...
In order to search for high-redshift galaxies beyond $z = 6.6$ in the Subaru Deep Field, we have investigated NB921-dropout galaxies where NB921 is the narrowband filter centered at 919.6 nm with...
New High-Redshift Galaxies at $z$ = 5.8 - 6.5 in the Subaru Deep Field (2005)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Ajiki, Masaru, Nagao, Tohru, Murayama, Takashi, Sasaki, Shunji, ...
In order to search for high-redshift galaxies around $z \sim 6$ in the Subaru Deep Field, we have investigated NB816-dropout galaxies where NB816 is the narrowband filter centered at 815nm with FWHM...
The Intermediate-band Dropout Method: A New Method to Search for High-Redshift Galaxies (2005)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Ajiki, Masaru, Nagao, Tohru, Murayama, Takashi, Sasaki, Shunji, ...
We propose a new method to search for high-redshift galaxies that is based on an intermediate-band dropout technique rather than the usual broad-band dropout one. In this method, we use an...
Subaru Deep Spectroscopy of a Star-forming Companion Galaxy of BR 1202-0725 at $z=4.7$ (2004)
Ohyama, Youichi, Taniguchi, Yoshiaki, Shioya, Yasuhiro
We present deep spatially-resolved optical spectroscopy of the NW companion galaxy of the quasar BR 1202-0725 at $z=4.7$. Its rest-frame UV spectrum shows star-forming activity in the nuclear region....
Nagao, Tohru, Kawabata, Koji S., Murayama, Takashi, Ohyama, Youichi, Taniguchi, Yoshiaki, Shioya, Yasuhiro, ...
We report on the result of our high quality spectropolarimetric observation for the narrow-line region in a nearby Seyfert 2 galaxy, Mrk 573, by the Subaru Telescope. The polarized flux spectrum of...
Cluster cannibalism and scaling relations of galactic stellar nuclei (2004)
Bekki, Kenji, Couch, Warrick J., Drinkwater, Michael J., Shioya, Yasuhiro
Recently, very massive compact stellar systems have been discovered in the intracluster regions of galaxy clusters and in the nuclear regions of late-type disk galaxies. It is unclear how these...
A Subaru Search for Lyman-Alpha Emitters at z=5.8 with an Intermediate-Band Filter (2004)
Ajiki, Masaru, Taniguchi, Yoshiaki, Fujita, Shinobu S., Shioya, Yasuhiro, Nagao, Tohru, Murayama, Takashi, ...
We present the results of a survey for Ly-alpha emitters at z ~ 5.8 using a new intermediate-band filter centered at lambda_c = 8275 AA with Delta-lambda_FWHM = 340 AA (i.e., the spectroscopic...
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J.
We numerically investigate the spectrophotometric evolution of galaxies with a variety of different star formation histories and degrees of dust extinction in order to elucidate the origin of the...
Cluster cannibalism and scaling relations of galactic stellar nuclei (2004)
Bekki, Kenji, Couch, Warrick J., Drinkwater, Michael J., Shioya, Yasuhiro
Recently, very massive compact stellar systems have been discovered in the intracluster regions of galaxy clusters and in the nuclear regions of late-type disk galaxies. It is unclear how these...
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J.
We numerically investigate the spectrophotometric evolution of galaxies with a variety of different star formation histories and degrees of dust extinction in order to elucidate the origin of the...
Cluster cannibalism and scaling relations of galactic stellar nuclei (2004)
Bekki, Kenji, Couch, Warrick J., Drinkwater, Michael J., Shioya, Yasuhiro
Recently, very massive compact stellar systems have been discovered in the intracluster regions of galaxy clusters and in the nuclear regions of late-type disk galaxies. It is unclear how these...
Detection of Molecular Clouds in the Interarm of the Flocculent Galaxy NGC 5055 (2003)
Tosaki, Tomoka, Shioya, Yasuhiro, Kuno, Nario, Nakanishi, Kouichiro, Hasegawa, Takashi
We present high-resolution (~ 4") 12CO (J = 1 - 0) mapping observations with high - velocity resolution (~ 2.6 km s^{-1}) toward the disk of flocculent galaxy NGC 5055, using the Nobeyama Millimeter...
The Halpha Luminosity Function of the Galaxy Cluster Abell 521 at z = 0.25 (2003)
Umeda, Kazuyoshi, Yagi, Masafumi, Yamada, Sanae F., Taniguchi, Yoshiaki, Shioya, Yasuhiro, Murayama, Takashi, ...
We present an optical multicolor-imaging study of the galaxy cluster Abell 521 at $z = 0.25$, using Suprime-Cam on the Subaru Telescope, covering an area of $32 \times 20$ arcmin$^2$ ($9.4 \times 5.8...
A Subaru Search for Lyman$\alpha$ Emitters at Redshift 5.7 (2003)
Ajiki, Masaru, Taniguchi, Yoshiaki, Fujita, Shinobu S., Shioya, Yasuhiro, Nagao, Tohru, Murayama, Takashi, ...
We present the results of a survey for Ly$\alpha$ emitters at $z\approx 5.7$ based on optical narrow-band ($\lambda_{\rm c} = 8150$ \AA ~ and $\Delta\lambda = 120$ \AA), and broad-band ($B$, $R_{\rm...
Are Two z~6 Quasars Gravitationally Lensed ? (2003)
Yamada, Sanae F., Shioya, Yasuhiro, Taniguchi, Yoshiaki, Murayama, Takashi, Ajiki, Masaru, Nagao, Tohru, ...
Several high-z (z > 5.7) quasars have been found in the course of Sloan Digital Sky Survey. The presence of such very high-z quasars is expected to give constraints on early structure formation. On...
Lyman$\alpha$ Emitters beyond Redshift 5:The Dawn of Galaxy Formation (2003)
Taniguchi, Yoshiaki, Shioya, Yasuhiro, Fujita, Shinobu S., Nagao, Tohru, Murayamaoya, Takashi, Ajiki, Masaru
The 8m class telescopes in the ground-based optical astronomy together with help from the ultra-sharp eye of the Hubble Space Telescope have enabled us to observe forming galaxies beyond redshift...
Subaru High-Dispersion Spectroscopy of Narrow-Line Region in the Seyfert Galaxy NGC 4151 (2003)
Nagao, Tohru, Murayama, Takashi, Shioya, Yasuhiro, Taniguchi, Yoshiaki
We report on a study of forbidden emission-line spectrum of nearby Seyfert 1.5 galaxy NGC 4151 based on the high-resolution (R ~ 45,000) optical spectrum obtained by using the High Dispersion...
The discovery of a very narrow line star-forming object at a redshift of 5.66 (2003)
Taniguchi, Yoshiaki, Ajiki, Masaru, Murayama, Takashi, Nagao, Tohru, Veilleux, Sylvain, Sanders, David B., ...
Nagao, Tohru, Murayama, Takashi, Shioya, Yasuhiro, Taniguchi, Yoshiaki
In order to examine whether or not high-ionization nuclear emission-line regions (HINERs) in narrow-line regions of active galactic nuclei are dusty, we focus on two high-ionization forbidden...
SDSSp J104433.04$-$012502.2 at $z=5.74$ is Gravitationally Magnified by an Intervening Galaxy (2002)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Murayama, Takashi, Ajki, Masaru, Nagao, Tohru, Fujita, Shinobu S., ...
During the course of our optical deep survey program on L$\alpha$ emitters at $z \approx 5.7$ in the sky area surrounding the quasar SDSSp J104433.04$-$012502.2 at $z=5.74$, we found that a faint...
A Search for Lyman alpha Emitters at Redshift 3.7 (2002)
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 ($\lambda_{\rm c}$ = 5736 \AA ~ and $\Delta\lambda$ = 280 \AA) and broad-band ($B$, $V$, $R$, and...
Passive spiral formation from halo gas starvation: Gradual transformation into S0s (2002)
Bekki, Kenji, Shioya, Yasuhiro, Couch, Warrick J.
Recent spectroscopic and high resolution $HST$-imaging observations have revealed significant numbers of ``passive'' spiral galaxies in distant clusters, with all the morphological hallmarks of a...
Effects of a burst of formation of first-generation stars on the evolution of galaxies (2002)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Murayama, Takashi, Nishiura, Shingo, Nagao, Tohru, Kakazu, Yuko
First-generation (Population III) stars in the universe play an important role inearly enrichment of heavy elements in galaxies and intergalactic medium and thus affect the history of galaxies. The...
Nagao, Tohru, Murayama, Takashi, Shioya, Yasuhiro, Taniguchi, Yoshiaki
We investigate gas metallicity of narrow-line regions in narrow-line Seyfert 1 galaxies (NLS1s) and broad-line ones (BLS1s) in order to examine whether or not there is a difference in the gas...
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J., De Propris, Roberto
A one-zone chemo-spectro-photometric model is used to investigate the time evolution of disk galaxies whose star formation is truncated, and to determine the dependence of this evolution on the...
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J., De Propris, Roberto
A one-zone chemospectrophotometric model is used to investigate the time evolution of disk galaxies whose star formation is truncated and to determine the dependence of this evolution on the previous...
Passive spiral formation from halo gas starvation: gradual transformation into S0s (2002)
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent spectroscopic and high-resolution Hubble Space Telescope (HST) imaging observations have revealed significant numbers of "passive" spiral galaxies in distant clusters, with all the...
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J., De Propris, Roberto
A one-zone chemospectrophotometric model is used to investigate the time evolution of disk galaxies whose star formation is truncated and to determine the dependence of this evolution on the previous...
Passive spiral formation from halo gas starvation: gradual transformation into S0s (2002)
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent spectroscopic and high-resolution Hubble Space Telescope (HST) imaging observations have revealed significant numbers of "passive" spiral galaxies in distant clusters, with all the...
Nagao, Tohru, Murayama, Takashi, Shioya, Yasuhiro, Taniguchi, Yoshiaki
In order to examine the prediction that the broad-line radio galaxies (BLRGs) with double-peaked Balmer lines harbor an accretion disk characterized by an advection-dominated accretion flow (ADAF) in...
Taniguchi, Yoshiaki, Shioya, Yasuhiro, Kakazu, Yuko
The most remarkable class of high-redshift objects observed so far is extended Ly$\alpha$ emission-line blobs found in an over-density region at redshift 3.1. They may be either a dust-enshrouded,...
A Shock-Induced Pair of Superbubbles in the High-Redshift Powerful Radio Galaxy MRC 0406-244 (2001)
Taniguchi, Yoshiaki, Ohyama, Youichi, Murayama, Takashi, Yoshida, Michitoshi, Kashikawa, Nobunari, Iye, Masanori, ...
We present new optical spectroscopy of the high-redshift powerful radio galaxy MRC 0406$-$244 at redshift of 2.429. We find that the two extensions toward NW and SE probed in the rest-frame...
Spectroscopic evolution of dusty starburst galaxies (2001)
Shioya, Yasuhiro, Bekki, Kenji, Couch, Warrick J.
By using a one-zone chemical and spectrophotometric evolution model of a disk galaxy undergoing a dusty starburst, we investigate, numerically, the optical spectroscopic properties in order to...
Bekki, Kenji, Couch, Warrick J., Shioya, Yasuhiro
Recent spectroscopic observations of galaxies in distant clusters have revealed that the rate of star formation in star-forming galaxies is significantly suppressed with respect to their counterparts...
Formation and evolution of E+A galaxies in dusty starburst galaxies (2000)
Bekki, Kenji, Shioya, Yasuhiro, Couch, Warrick J.
The formation and evolution of the ``E+A'' (also named ``k+a'' and ``a+k'' types by Dressler et al. 1999) galaxies found in significant numbers in the cores of intermediate redshift clusters has been...
Bekki, Kenji, Shioya, Yasuhiro
By performing N-body simulations of chemodynamical evolution of galaxies with dusty starbursts, we investigate photometric evolution of gas-rich major mergers in order to explore the nature of...
ALMA and high redshift dusty starburst mergers (2000)
Bekki, Kenji, Shioya, Yasuhiro
By using a new numerical code for deriving the spectral energy distributions of galaxies, we have investigated the time evolution of morphological properties, the star formation rate, and the...
On the Hidden Nuclear Starburst in Arp 220 (2000)
Shioya, Yasuhiro, Trentham, Neil, Taniguchi, Yoshiaki
We construct a starburst model for the hidden starbursts in Arp 220 based on the new Starburst99 models of Leitherer et al. Comparing these stellar population synthesis models with observations, we...
A New interpretation of chain galaxies at high redshift (2000)
Taniguchi, Yoshiaki, Shioya, Yasuhiro
We propose a possible new model for the formation of chain galaxies at high redshift. Our model is summarized as follows. Step I: Successive merging of subgalactic gas clumps results in the formation...
Photometric Properties of the Arp 220 Super Star Clusters (2000)
Shioya, Yasuhiro, Taniguchi, Yoshiaki, Trentham, Neil
We investigate the photometric properties of six super stellar clusters (SSCs) seen in both the optical and near-infrared Hubble Space Telescope images of the local ultraluminous starburst galaxy Arp...
Shioya, Yasuhiro, Bekki, Kenji
Recent observational studies on galaxies in distant clusters discovered a significant fraction of possible dusty starburst galaxies with the so-called `e(a)' spectra that are characterized by strong...
Poststarburst Models of LINERs (2000)
Taniguchi, Yoshiaki, Shioya, Yasuhiro, Murayama, Takashi
Since the discovery of low-ionization nuclear emission-line regions in many galaxies (LINERs), it has been recognized that they constitute a class of active galactic nuclei (AGNs) which are thought...
Bekki, Kenji, Shioya, Yasuhiro
We present a new numerical code which is designed to derive a spectral energy distribution (SED) for an arbitrary spatial distribution of stellar and gaseous components in a dusty starburst galaxy....
Formation of intermediate-mass black holes in circumnuclear regions of galaxies (2000)
Taniguchi, Yoshiaki, Shioya, Yasuhiro, Tsuru, Takeshi G., Ikeuchi, Satoru
Recent high-resolution X-ray imaging studies have discovered possible candidates of intermediate-mass black holes with masses of $M_\bullet \sim 10^{2-4} \MO$ in circumnuclear regions of many (disk)...
Superwind model of extended Lyman alpha emitters at high redshift (2000)
Taniguchi, Yoshiaki, Shioya, Yasuhiro
We propose a new model for the extended Ly alpha blobs found recently at high redshift z ~ 3. The observational properties of these blobs are; 1) the observed Ly alpha luminosities are ~ 10^{43}...
Bekki, Kenji, Shioya, Yasuhiro, Tanaka, Ichi
We investigate when and how a dusty starburst galaxy merger can be heavily obscured by dust and consequently becomes an ultra-luminous infrared galaxy (ULIRG), based on numerical simulations of...
Formation of Quasar Nuclei in the Heart of Ultraluminous Infrared Galaxies (1999)
Taniguchi, Yoshiaki, Shioya, Yasuhiro
We investigate whether or not a supermassive black hole (SMBH) with mass $\gtrsim 10^8 M_\odot$ can be made in the heart of ultraluminous infrared galaxies (ULIGs) during the course of mergers...
Bekki, Kenji, Shioya, Yasuhiro
We numerically investigate chemodynamical evolution of major disk-disk galaxy mergers in order to explore the origin of mass-dependent chemical, photometric, and spectroscopic properties observed in...
Starburst-driven Starbursts in the Heart of Ultraluminous Infrared Galaxies (1998)
Taniguchi, Yoshiaki, Trentham, Neil, Shioya, Yasuhiro
There is increasing evidence for the presence of blue super star clusters in the central regions of ultraluminous infrared galaxies like Arp 220. Ultraluminous galaxies are thought to be triggered by...
A Multiple Merger Model for the Origin of Ultraluminous Infrared Galaxies (1998)
Taniguchi, Yoshiaki, Shioya, Yasuhiro
It has been often considered that the dissipative collapse caused by a merger of two gas-rich galaxies is responsible for the intense nuclear starbursts or the nonthermal quasar activity in...
Shioya, Yasuhiro, Bekki, Kenji
We investigate a one-zone chemophotometric evolution model of disk-disk galaxy mergers in order to clarify whether or not galaxy mergers with the widely spread merging epoch can reproduce reasonably...
Stellar populations in gas-rich galaxy mergers I. Dependence on star formation history (1998)
Bekki, Kenji, Shioya, Yasuhiro
We investigate the nature of stellar populations of major galaxy mergers between late-type spirals considerably abundant in interstellar medium by performing numerical simulations designed to solve...