Hiroya Umeda

2.2k total citations · 4 hit papers
21 papers, 1.0k citations indexed

About

Hiroya Umeda is a scholar working on Astronomy and Astrophysics, Instrumentation and Nuclear and High Energy Physics. According to data from OpenAlex, Hiroya Umeda has authored 21 papers receiving a total of 1.0k indexed citations (citations by other indexed papers that have themselves been cited), including 21 papers in Astronomy and Astrophysics, 8 papers in Instrumentation and 4 papers in Nuclear and High Energy Physics. Recurrent topics in Hiroya Umeda's work include Galaxies: Formation, Evolution, Phenomena (21 papers), Astrophysical Phenomena and Observations (11 papers) and Astronomy and Astrophysical Research (8 papers). Hiroya Umeda is often cited by papers focused on Galaxies: Formation, Evolution, Phenomena (21 papers), Astrophysical Phenomena and Observations (11 papers) and Astronomy and Astrophysical Research (8 papers). Hiroya Umeda collaborates with scholars based in Japan, United States and United Kingdom. Hiroya Umeda's co-authors include Masami Ouchi, Yuichi Harikane, Kimihiko Nakajima, Yoshiaki Ono, Yuki Isobe, Yechi Zhang, Yi Xu, Masamune Oguri, Ken Mawatari and Hidenobu Yajima and has published in prestigious journals such as The Astrophysical Journal, The Astrophysical Journal Supplement Series and Publications of the Astronomical Society of Japan.

In The Last Decade

Hiroya Umeda

21 papers receiving 733 citations

Hit Papers

A Comprehensive Study of Galaxies at z ∼ 9–16 Found in th... 2023 2026 2024 2025 2023 2023 2023 2023 50 100 150 200 250
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. 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
    2023 292 citations Yuichi Harikane, Masami Ouchi et al. The Astrophysical Journal Supplement Series profile →
  2. 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
    2023 230 citations Yuichi Harikane, Yechi Zhang et al. The Astrophysical Journal profile →
  3. JWST Census for the Mass–Metallicity Star Formation Relations at z = 4–10 with Self-consistent Flux Calibration and Proper Metallicity Calibrators
    2023 111 citations Kimihiko Nakajima, Masami Ouchi et al. The Astrophysical Journal Supplement Series profile →
  4. 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
    2023 89 citations Yuichi Harikane, Kimihiko Nakajima et al. The Astrophysical Journal profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Hiroya Umeda Japan 10 923 398 149 42 31 21 1.0k
Yechi Zhang Japan 10 904 1.0× 397 1.0× 146 1.0× 43 1.0× 29 0.9× 21 1.0k
Antonino Marasco Italy 25 1.4k 1.5× 553 1.4× 207 1.4× 46 1.1× 69 2.2× 53 1.4k
John Chisholm United States 24 1.5k 1.7× 543 1.4× 186 1.2× 40 1.0× 67 2.2× 75 1.6k
Aaron Smith United States 16 938 1.0× 310 0.8× 260 1.7× 28 0.7× 28 0.9× 54 1.1k
K. Małek Poland 17 917 1.0× 364 0.9× 213 1.4× 64 1.5× 39 1.3× 87 997
A. Streblyanska Spain 13 1.1k 1.1× 310 0.8× 280 1.9× 19 0.5× 39 1.3× 33 1.1k
Ákos Bogdán United States 16 958 1.0× 213 0.5× 309 2.1× 22 0.5× 29 0.9× 52 1.0k
Fergus Cullen United Kingdom 23 1.7k 1.8× 867 2.2× 165 1.1× 32 0.8× 69 2.2× 62 1.7k
Yueying Ni United States 17 662 0.7× 179 0.4× 203 1.4× 20 0.5× 19 0.6× 58 740
Maxime Trebitsch France 15 831 0.9× 276 0.7× 201 1.3× 21 0.5× 31 1.0× 34 906

Countries citing papers authored by Hiroya Umeda

Since Specialization
Citations

This map shows the geographic impact of Hiroya Umeda's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Hiroya Umeda with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Hiroya Umeda more than expected).

Fields of papers citing papers by Hiroya Umeda

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Hiroya Umeda. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Hiroya Umeda. The network helps show where Hiroya Umeda may publish in the future.

Co-authorship network of co-authors of Hiroya Umeda

This figure shows the co-authorship network connecting the top 25 collaborators of Hiroya Umeda. A scholar is included among the top collaborators of Hiroya Umeda based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Hiroya Umeda. Hiroya Umeda is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
2.
Ouchi, Masami, Hiroya Umeda, Yuichi Harikane, et al.. (2025). Census of Lyα Emission from ∼600 Galaxies at z = 5–14: Evolution of the Lyα Luminosity Function and a Late Sharp Cosmic Reionization. The Astrophysical Journal Supplement Series. 278(2). 33–33. 6 indexed citations
3.
Xu, Yi, Masami Ouchi, Kimihiko Nakajima, et al.. (2025). Stellar- and AGN-driven Outflows in JWST Galaxies at z = 3–9: More Frequent, Wider Opening Angles, and Mostly Bounded. The Astrophysical Journal. 984(2). 182–182. 5 indexed citations
4.
Ouchi, Masami, Kimihiko Nakajima, Yuichi Harikane, et al.. (2025). A Galaxy with an Extremely Blue Ultraviolet Slope β = −3 at z = 9.25 Identified by JWST Spectroscopy: Evidence for a Weak Nebular Continuum and Efficient Ionizing Photon Escape?. The Astrophysical Journal. 988(1). 86–86. 3 indexed citations
5.
Zhang, Yechi, Masami Ouchi, Kimihiko Nakajima, et al.. (2024). Statistics for Galaxy Outflows at z ∼ 6–9 with Imaging and Spectroscopic Signatures Identified with JWST/NIRCam and NIRSpec Data. The Astrophysical Journal. 970(1). 19–19. 9 indexed citations
6.
Xu, Yi, Masami Ouchi, Hidenobu Yajima, et al.. (2024). Dynamics of a Galaxy at z > 10 Explored by JWST Integral Field Spectroscopy: Hints of Rotating Disk Suggesting Weak Feedback. The Astrophysical Journal. 976(1). 142–142. 7 indexed citations
7.
Ouchi, Masami, Kimihiko Nakajima, Hidenobu Yajima, et al.. (2024). 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?. The Astrophysical Journal. 974(2). 266–266. 7 indexed citations
8.
Ouchi, Masami, Kimihiko Nakajima, Yuichi Harikane, et al.. (2024). Lyα Emission at z = 7–13: Clear Evolution of Lyα Equivalent Width Indicating a Late Cosmic Reionization History. The Astrophysical Journal. 967(1). 28–28. 35 indexed citations
9.
Ono, Yoshiaki, Yuichi Harikane, Masami Ouchi, et al.. (2024). Census for the rest-frame optical and UV morphologies of galaxies at z = 4–10: First phase of inside-out galaxy formation. Publications of the Astronomical Society of Japan. 76(2). 219–250. 6 indexed citations
10.
Ouchi, Masami, Kimihiko Nakajima, Hidenobu Yajima, et al.. (2024). Balmer Decrement Anomalies in Galaxies at z ∼ 6 Found by JWST Observations: Density-bounded Nebulae or Excited H i Clouds?. The Astrophysical Journal. 974(2). 180–180. 9 indexed citations
11.
Ouchi, Masami, Hiroya Umeda, Kimihiko Nakajima, et al.. (2024). 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 ⊙. The Astrophysical Journal. 966(2). 170–170. 7 indexed citations
12.
Umeda, Hiroya, Masami Ouchi, Kimihiko Nakajima, et al.. (2024). 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. The Astrophysical Journal. 971(2). 124–124. 38 indexed citations
13.
Harikane, Yuichi, Masami Ouchi, Masamune Oguri, et al.. (2023). 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. The Astrophysical Journal Supplement Series. 265(1). 5–5. 292 indexed citations breakdown →
14.
Ono, Yoshiaki, Yuichi Harikane, Masami Ouchi, et al.. (2023). 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. The Astrophysical Journal. 951(1). 72–72. 37 indexed citations
15.
Nakajima, Kimihiko, Masami Ouchi, Yuki Isobe, et al.. (2023). JWST Census for the Mass–Metallicity Star Formation Relations at z = 4–10 with Self-consistent Flux Calibration and Proper Metallicity Calibrators. The Astrophysical Journal Supplement Series. 269(2). 33–33. 111 indexed citations breakdown →
16.
Kikuta, Satoshi, Masami Ouchi, Takatoshi Shibuya, et al.. (2023). 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. The Astrophysical Journal Supplement Series. 268(1). 24–24. 7 indexed citations
17.
Isobe, Yuki, Masami Ouchi, Kimihiko Nakajima, et al.. (2023). Redshift Evolution of Electron Density in the Interstellar Medium at z ∼ 0–9 Uncovered with JWST/NIRSpec Spectra and Line-spread Function Determinations. The Astrophysical Journal. 956(2). 139–139. 53 indexed citations
18.
Harikane, Yuichi, Kimihiko Nakajima, Masami Ouchi, et al.. (2023). 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. The Astrophysical Journal. 960(1). 56–56. 89 indexed citations breakdown →
19.
Harikane, Yuichi, Yechi Zhang, Kimihiko Nakajima, et al.. (2023). 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. The Astrophysical Journal. 959(1). 39–39. 230 indexed citations breakdown →
20.
Umeda, Hiroya, Masami Ouchi, Kimihiko Nakajima, et al.. (2022). EMPRESS. VII. Ionizing Spectrum Shapes of Extremely Metal-poor Galaxies: Uncovering the Origins of Strong He ii and the Impact on Cosmic Reionization. The Astrophysical Journal. 930(1). 37–37. 22 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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