Search Results - "Nakajima, Kimihiko"

Ionization state of inter-stellar medium in galaxies: evolution, SFR–M –Z dependence, and ionizing photon escape by Nakajima, Kimihiko, Ouchi, Masami

“…We present a systematic study for ionization state of inter-stellar medium in galaxies at z = 0– with ∼140 000 Sloan Digital Sky Survey (SDSS) galaxies and 108…”
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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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The Lyman Continuum Escape Survey. II. Ionizing Radiation as a Function of the [O iii]/[O ii] Line Ratio by Nakajima, Kimihiko, Ellis, Richard S., Robertson, Brant E., Tang, Mengtao, Stark, Daniel P.

“…We discuss the rest-frame optical emission line spectra of a large (∼50) sample of z ∼ 3.1 Ly emitting galaxies (LAEs) whose physical properties suggest such…”
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The mean ultraviolet spectrum of a representative sample of faint z ∼ 3 Lyman alpha emitters by Nakajima, Kimihiko, Fletcher, Thomas, Ellis, Richard S, Robertson, Brant E, Iwata, Ikuru

“…Abstract We discuss the rest-frame ultraviolet (UV) emission line spectra of a large (∼100) sample of low luminosity redshift z ∼ 3.1 Lyman alpha emitters…”
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The Lyman Continuum Escape Survey: Ionizing Radiation from [O iii]-strong Sources at a Redshift of 3.1 by Fletcher, Thomas J., Tang, Mengtao, Robertson, Brant E., Nakajima, Kimihiko, Ellis, Richard S., Stark, Daniel P., Inoue, Akio

“…We present results from the LymAn Continuum Escape Survey (LACES), a Hubble Space Telescope (HST) program designed to characterize the ionizing radiation…”
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A Spectroscopic Search for AGN Activity in the Reionization Era by Laporte, Nicolas, Nakajima, Kimihiko, Ellis, Richard S., Zitrin, Adi, Stark, Daniel P., Mainali, Ramesh, Roberts-Borsani, G. W.

“…The ubiquity of Lyman alpha (Ly ) emission in a sample of four bright [O iii]-strong star-forming galaxies with redshifts above seven has led to the suggestion…”
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Toward Unveiling Cosmic Reionization: The Ionizing Photon Production Efficiency (ξ ion) of Low-mass Hα Emitters at z ∼ 2.3 by Chen, Nuo, Motohara, Kentaro, Spitler, Lee, Nakajima, Kimihiko, Terao, Yasunori

“…We investigate the galaxy properties of ∼400 low-mass (<109M⊙) Hα emitters (HAEs) at z ∼ 2.3 in the ZFOURGE survey. The selection of these HAEs is based on 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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Evolution of N/O abundance ratios and ionization parameters from z ∼ 0 to 2 investigated by the direct temperature method by Kojima, Takashi, Ouchi, Masami, Nakajima, Kimihiko, Shibuya, Takatoshi, Harikane, Yuichi, Ono, Yoshiaki

“…Abstract We present N/O abundance ratios, ionization parameters q ion, and oxygen abundances O/H for a total of 41 galaxies (11 individual galaxies and a…”
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EMPRESS. V. Metallicity Diagnostics of Galaxies over 12 + log(O/H) ≃ 6.9–8.9 Established by a Local Galaxy Census: Preparing for JWST Spectroscopy by Nakajima, Kimihiko, Ouchi, Masami, Xu, Yi, Rauch, Michael, Harikane, Yuichi, Nishigaki, Moka, Isobe, Yuki, Kusakabe, Haruka, Nagao, Tohru, Ono, Yoshiaki, Onodera, Masato, Sugahara, Yuma, Kim, Ji Hoon, Komiyama, Yutaka, Lee, Chien-Hsiu, Zahedy, Fakhri S.

“…Abstract We present optical-line gas metallicity diagnostics established by the combination of local SDSS galaxies and the largest compilation of extremely…”
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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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Observational properties of a general relativistic instability supernova from a primordial supermassive star by Moriya, Takashi J, Chen, Ke-Jung, Nakajima, Kimihiko, Tominaga, Nozomu, Blinnikov, Sergei I

“…ABSTRACT We present the expected observational properties of a general relativistic instability supernova (GRSN) from the 55 500 M⊙ primordial (Population III)…”
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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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Broadband Selection, Spectroscopic Identification, and Physical Properties of a Population of Extreme Emission-line Galaxies at 3 < z < 3.7 by Onodera, Masato, Shimakawa, Rhythm, Suzuki, Tomoko L., Tanaka, Ichi, Harikane, Yuichi, Hayashi, Masao, Kodama, Tadayuki, Koyama, Yusei, Nakajima, Kimihiko, Shibuya, Takatoshi

“…Abstract We present the selection, spectroscopic identification, and physical properties of extreme emission-line galaxies (EELGs) at 3 <  z  < 3.7, aiming at…”
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