Search Results - "Umeda, Hiroya"

A Comprehensive Study of Galaxies at z ∼ 9–16 Found in the Early JWST Data: Ultraviolet Luminosity Functions and Cosmic Star Formation History at the Pre-reionization Epoch by Harikane, Yuichi, Ouchi, Masami, Oguri, Masamune, Ono, Yoshiaki, Nakajima, Kimihiko, Isobe, Yuki, Umeda, Hiroya, Mawatari, Ken, Zhang, Yechi

“…Abstract We conduct a comprehensive study on dropout galaxy candidates at z ∼ 9–16 using the first 90 arcmin 2 James Webb Space Telescope (JWST) Near Infrared…”
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A JWST/NIRSpec First Census of Broad-line AGNs at z = 4–7: Detection of 10 Faint AGNs with M BH ∼ 106–108 M ⊙ and Their Host Galaxy Properties by Harikane, Yuichi, Zhang, Yechi, Nakajima, Kimihiko, Ouchi, Masami, Isobe, Yuki, Ono, Yoshiaki, Hatano, Shun, Xu, Yi, Umeda, Hiroya

“…We present the first statistical sample of faint type 1 AGNs at z > 4 identified by JWST/NIRSpec deep spectroscopy. Among the 185 galaxies at z _spec = 3.8–8.9…”
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JWST Census for the Mass–Metallicity Star Formation Relations at z = 4–10 with Self-consistent Flux Calibration and Proper Metallicity Calibrators by Nakajima, Kimihiko, Ouchi, Masami, Isobe, Yuki, Harikane, Yuichi, Zhang, Yechi, Ono, Yoshiaki, Umeda, Hiroya, Oguri, Masamune

“…Abstract We present the evolution of the mass–metallicity (MZ) relation at z = 4–10 derived with 135 galaxies identified in JWST/NIRSpec data taken from the…”
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Morphologies of Galaxies at z ≳ 9 Uncovered by JWST/NIRCam Imaging: Cosmic Size Evolution and an Identification of an Extremely Compact Bright Galaxy at z ∼ 12 by Ono, Yoshiaki, Harikane, Yuichi, Ouchi, Masami, Yajima, Hidenobu, Abe, Makito, Isobe, Yuki, Shibuya, Takatoshi, Wise, John H., Zhang, Yechi, Nakajima, Kimihiko, Umeda, Hiroya

“…Abstract We present morphologies of galaxies at z ≳ 9 resolved by JWST/NIRCam 2–5 μ m imaging. Our sample consists of 22 galaxy candidates identified by…”
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EMPRESS. VII. Ionizing Spectrum Shapes of Extremely Metal-poor Galaxies: Uncovering the Origins of Strong He ii and the Impact on Cosmic Reionization by Umeda, Hiroya, Ouchi, Masami, Nakajima, Kimihiko, Isobe, Yuki, Aoyama, Shohei, Harikane, Yuichi, Ono, Yoshiaki, Matsumoto, Akinori

“…Abstract Strong high-ionization lines such as He ii of young galaxies are puzzling at high and low redshift. Although recent studies suggest the existence of…”
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Redshift Evolution of Electron Density in the Interstellar Medium at z ∼ 0–9 Uncovered with JWST/NIRSpec Spectra and Line-spread Function Determinations by Isobe, Yuki, Ouchi, Masami, Nakajima, Kimihiko, Harikane, Yuichi, Ono, Yoshiaki, Xu, Yi, Zhang, Yechi, Umeda, Hiroya

“…Abstract We present electron densities n e in the interstellar medium (ISM) of star-forming galaxies at z = 4–9 observed by the JWST/NIRSpec GLASS, Early…”
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Lyα Emission at z = 7–13: Clear Evolution of Lyα Equivalent Width Indicating a Late Cosmic Reionization History by Nakane, Minami, Ouchi, Masami, Nakajima, Kimihiko, Harikane, Yuichi, Ono, Yoshiaki, Umeda, Hiroya, Isobe, Yuki, Zhang, Yechi, Xu, Yi

“…Abstract We present the evolution of Ly α emission derived from 53 galaxies at z = 6.6–13.2, which have been identified by multiple JWST/NIRSpec spectroscopy…”
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JWST Identification of Extremely Low C/N Galaxies with [N/O] ≳ 0.5 at z ∼ 6–10 Evidencing the Early CNO-cycle Enrichment and a Connection with Globular Cluster Formation by Isobe, Yuki, Ouchi, Masami, Tominaga, Nozomu, Watanabe, Kuria, Nakajima, Kimihiko, Umeda, Hiroya, Yajima, Hidenobu, Harikane, Yuichi, Fukushima, Hajime, Xu, Yi, Ono, Yoshiaki, Zhang, Yechi

“…Abstract We present chemical abundance ratios of 70 star-forming galaxies at z ∼ 4–10 observed by the JWST/NIRSpec Early Release Observations, GLASS, and CEERS…”
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JWST Measurements of Neutral Hydrogen Fractions and Ionized Bubble Sizes at z = 7–12 Obtained with Lyα Damping Wing Absorptions in 27 Bright Continuum Galaxies by Umeda, Hiroya, Ouchi, Masami, Nakajima, Kimihiko, Harikane, Yuichi, Ono, Yoshiaki, Xu, Yi, Isobe, Yuki, Zhang, Yechi

“…Abstract We present volume-averaged neutral hydrogen fractions x H I and ionized bubble radii R b measured with Ly α damping wing absorption of galaxies at the…”
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Statistics for Galaxy Outflows at z ∼ 6–9 with Imaging and Spectroscopic Signatures Identified with JWST/NIRCam and NIRSpec Data by Zhang, Yechi, Ouchi, Masami, Nakajima, Kimihiko, Harikane, Yuichi, Isobe, Yuki, Xu, Yi, Ono, Yoshiaki, Umeda, Hiroya

“…Abstract We present statistics of z ∼ 6–9 galaxy outflows indicated by spatially extended gas emission and broad lines. With a total of 61 spectroscopically…”
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Pure Spectroscopic Constraints on UV Luminosity Functions and Cosmic Star Formation History from 25 Galaxies at z spec = 8.61–13.20 Confirmed with JWST/NIRSpec by Harikane, Yuichi, Nakajima, Kimihiko, Ouchi, Masami, Umeda, Hiroya, Isobe, Yuki, Ono, Yoshiaki, Xu, Yi, Zhang, Yechi

“…Abstract We present pure spectroscopic constraints on the UV luminosity functions and cosmic star formation rate (SFR) densities from 25 galaxies at z spec =…”
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Balmer Decrement Anomalies in Galaxies at z ∼ 6 Found by JWST Observations: Density-bounded Nebulae or Excited H i Clouds? by Yanagisawa, Hiroto, Ouchi, Masami, Nakajima, Kimihiko, Yajima, Hidenobu, Umeda, Hiroya, Baba, Shunsuke, Nakagawa, Takao, Nakane, Minami, Matsumoto, Akinori, Ono, Yoshiaki, Harikane, Yuichi, Isobe, Yuki, Xu, Yi, Zhang, Yechi

“…Abstract We investigate the physical origins of the Balmer decrement anomalies in GS-NDG-9422 and RXCJ2248-ID galaxies at z ∼ 6 whose H α /H β values are…”
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Strong He i Emission Lines in High N/O Galaxies at z ∼ 6 Identified in JWST Spectra: High He/H Abundance Ratios or High Electron Densities? by Yanagisawa, Hiroto, Ouchi, Masami, Watanabe, Kuria, Matsumoto, Akinori, Nakajima, Kimihiko, Yajima, Hidenobu, Nagamine, Kentaro, Takahashi, Koh, Nakane, Minami, Tominaga, Nozomu, Umeda, Hiroya, Fukushima, Hajime, Harikane, Yuichi, Isobe, Yuki, Ono, Yoshiaki, Xu, Yi, Zhang, Yechi

“…Abstract We present He i /H β flux and He/H abundance ratios in three James Webb Space Telescope galaxies with significant constraints on N/O abundance ratios,…”
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EMPRESS. XIV. Strong High-ionization Lines of Young Galaxies at z = 0–8: Ionizing Spectra Consistent with the Intermediate-mass Black Holes with M BH ∼ 103–106 M by Hatano, Shun, Ouchi, Masami, Umeda, Hiroya, Nakajima, Kimihiko, Kawaguchi, Toshihiro, Isobe, Yuki, Aoyama, Shohei, Watanabe, Kuria, Harikane, Yuichi, Kusakabe, Haruka, Matsumoto, Akinori, Moriya, Takashi J., Nishigaki, Moka, Ono, Yoshiaki, Onodera, Masato, Sugahara, Yuma, Suzuki, Akihiro, Xu, Yi, Zhang, Yechi

“…We present ionizing spectra estimated at 13.6–100 eV for 10 dwarf galaxies with strong high-ionization lines of He ii λ 4686 and [Ne v ] λ 3426 ([Ne iv ] λ…”
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SILVERRUSH. XIII. A Catalog of 20,567 Lyα Emitters at z = 2−7 Identified in the Full-depth Data of the Subaru/HSC-SSP and CHORUS Surveys by Kikuta, Satoshi, Ouchi, Masami, Shibuya, Takatoshi, Liang, Yongming, Umeda, Hiroya, Matsumoto, Akinori, Shimasaku, Kazuhiro, Harikane, Yuichi, Ono, Yoshiaki, Inoue, Akio K., Yamanaka, Satoshi, Kusakabe, Haruka, Momose, Rieko, Kashikawa, Nobunari, Matsuda, Yuichi, Lee, Chien-Hsiu

“…Abstract We present 20,567 Ly α emitters (LAEs) at z = 2.2 − 7.3 that are photometrically identified by the SILVERRUSH program in a large survey area up to 25…”
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Pure Spectroscopic Constraints on UV Luminosity Functions and Cosmic Star Formation History from 25 Galaxies at zspec = 8.61–13.20 Confirmed with JWST/NIRSpec by Harikane, Yuichi, Nakajima, Kimihiko, Ouchi, Masami, Umeda, Hiroya, Isobe, Yuki, Ono, Yoshiaki, Xu, Yi, Zhang, Yechi

“…We present pure spectroscopic constraints on the UV luminosity functions and cosmic star formation rate (SFR) densities from 25 galaxies at zspec = 8.61–13.20…”
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A JWST/NIRSpec First Census of Broad-line AGNs at z = 4–7: Detection of 10 Faint AGNs with M BH ∼ 10 6 –10 8 M ⊙ and Their Host Galaxy Properties by Harikane, Yuichi, Zhang, Yechi, Nakajima, Kimihiko, Ouchi, Masami, Isobe, Yuki, Ono, Yoshiaki, Hatano, Shun, Xu, Yi, Umeda, Hiroya

“…Abstract We present the first statistical sample of faint type 1 AGNs at z > 4 identified by JWST/NIRSpec deep spectroscopy. Among the 185 galaxies at z spec =…”
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A JWST/NIRSpec First Census of Broad-line AGNs at z = 4–7: Detection of 10 Faint AGNs with MBH ∼ 106–108M⊙ and Their Host Galaxy Properties by Harikane, Yuichi, Zhang, Yechi, Nakajima, Kimihiko, Ouchi, Masami, Isobe, Yuki, Ono, Yoshiaki, Hatano, Shun, Xu, Yi, Umeda, Hiroya

“…We present the first statistical sample of faint type 1 AGNs at z > 4 identified by JWST/NIRSpec deep spectroscopy. Among the 185 galaxies at zspec = 3.8–8.9…”
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EMPRESS. VIII. A New Determination of Primordial He Abundance with Extremely Metal-poor Galaxies: A Suggestion of the Lepton Asymmetry and Implications for the Hubble Tension by Matsumoto, Akinori, Ouchi, Masami, Nakajima, Kimihiko, Kawasaki, Masahiro, Murai, Kai, Motohara, Kentaro, Harikane, Yuichi, Ono, Yoshiaki, Kushibiki, Kosuke, Koyama, Shuhei, Aoyama, Shohei, Konishi, Masahiro, Takahashi, Hidenori, Isobe, Yuki, Umeda, Hiroya, Sugahara, Yuma, Onodera, Masato, Nagamine, Kentaro, Kusakabe, Haruka, Hirai, Yutaka, Moriya, Takashi J., Shibuya, Takatoshi, Komiyama, Yutaka, Fukushima, Keita, Fujimoto, Seiji, Hattori, Takashi, Hayashi, Kohei, Inoue, Akio K., Kikuchihara, Shotaro, Kojima, Takashi, Koyama, Yusei, Lee, Chien-Hsiu, Mawatari, Ken, Miyata, Takashi, Nagao, Tohru, Ozaki, Shinobu, Rauch, Michael, Saito, Tomoki, Suzuki, Akihiro, Takeuchi, Tsutomu T., Umemura, Masayuki, Xu, Yi, Yabe, Kiyoto, Zhang, Yechi, Yoshii, Yuzuru

“…Abstract The primordial He abundance Y P is a powerful probe of cosmology. Currently, Y P is best determined by observations of metal-poor galaxies, while…”
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Census for the rest-frame optical and UV morphologies of galaxies at z = 4–10: First phase of inside-out galaxy formation by Ono, Yoshiaki, Harikane, Yuichi, Ouchi, Masami, Nakajima, Kimihiko, Isobe, Yuki, Shibuya, Takatoshi, Nakane, Minami, Umeda, Hiroya, Xu, Yi, Zhang, Yechi

“…Abstract We present the rest-frame optical and UV surface brightness (SB) profiles for 149 galaxies with Mopt < −19.4 mag at z = 4–10 (29 of which are…”
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