すばる望遠鏡大規模銀河探査で探る宇宙再電離史

• Project/Area Number: 16J07046
• Research Category: Grant-in-Aid for JSPS Fellows
• Allocation Type: Single-year Grants
• Section: 国内
• Research Field: Astronomy
• Research Institution: The University of Tokyo
• Principal Investigator: 澁谷 隆俊 東京大学, 宇宙線研究所, 特別研究員(PD) (30713995)
• Project Period (FY): 2016-04-22 – 2019-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 銀河天文学 / 宇宙再電離 / 銀河形成

Outline of Annual Research Achievements

初期宇宙において 銀河間空間の中性水素が大規模に電離される現象を「宇宙再電離」と呼ぶが，赤方偏移(z)~10から6の間の宇宙再電離史, 電離源は詳しく分かっていない．本研究の目標は, Lyα輝線銀河(LAE)を用いて, 6<z<7の時代の中性度, 宇宙再電離の空間的進行度について制限を付けることである．特別研究員 任期初年度から第2年度にかけて，すばる望遠鏡 Hyper Suprime-Cam (HSC) データを用いてz~6-7のLAE選択方法を確立し，合計約2000個のLAE候補天体を発見した (Shibuya+2018a)．これらのz~6-7 LAE候補天体のLyα光の空間的広がりやLyα輝線等価幅頻度分布など，測光的性質を統計的に調べた．構築したLAEサンプルは，遠方銀河の星間物質の研究などに広く使用されている (e.g., Harikane+2018)．
さらにLAE候補天体の中から Lyα光度が~10^43 erg/sより明るいLAEの分光観測も行い，LAEの静止紫外線輝線の検出率，輝線等価幅などを測定した(Shibuya+2018b)．分光観測初期成果を論文としてまとめた後も，LAEの分光的性質をより詳しく調べるため，すばる望遠鏡, ケック望遠鏡などの観測提案書を作成・提出した．いくつかの提案書が採択され，観測予定である (e.g., Shibuya+, S18A-107)．
HSCによるLAE研究を進める一方で，LAEの銀河形態研究も行った．ハッブル宇宙望遠鏡の高解像度データを用いて，約1万個のLAEの銀河表面輝度プロファイルの傾き，サイズを測定し，それらの赤方偏移進化を調べた．測定の結果，LAEは典型的に円盤型の銀河表面輝度プロファイルを持ち，他の銀河種族と同様にサイズ進化している可能性があることが分かった (Shibuya+2018c)．

Research Progress Status

翌年度、交付申請を辞退するため、記入しない。

Strategy for Future Research Activity

翌年度、交付申請を辞退するため、記入しない。

Research Products

• [Journal Article] The Hyper Suprime-Cam SSP Survey: Overview and survey design (2018)
  • Author(s): Aihara Hiroaki、Arimoto Nobuo、Armstrong Robert、 et al. (including Imanishi M.)
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-15
  • DOI: 10.1093/pasj/psx066
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] First data release of the Hyper Suprime-Cam Subaru Strategic Program (2018)
  • Author(s): Aihara Hiroaki、Armstrong Robert、Bickerton Steven、et al. (including Imanishi M.)
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-34
  • DOI: 10.1093/pasj/psx081
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Great Optically Luminous Dropout Research Using Subaru HSC (GOLDRUSH). I. UV luminosity functions at z ~ 4-7 derived with the half-million dropouts on the 100 deg2 sky (2018)
  • Author(s): Ono, Y., Shimasaku, K. et al. (26 authors in total)
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-29
  • DOI: 10.1093/pasj/psx103
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program strategy and clustering properties of ~ 2000 Lyα emitters at z = 6-7 over the 0.3-0.5 Gpc2 survey area (2018)
  • Author(s): Ouchi, M., Shimasaku, K. et al. (20 authors in total)
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-16
  • DOI: 10.1093/pasj/psx074
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Large-scale Environment of a z = 6.61 Luminous Quasar Probed by Lyα Emitters and Lyman Break Galaxies (2018)
  • Author(s): Ota Kazuaki、Venemans Bram P.、Taniguchi Yoshiaki、Kashikawa Nobunari、Nakata Fumiaki、Harikane Yuichi、Banados Eduardo、Overzier Roderik、Riechers Dominik A.、Walter Fabian、Toshikawa Jun、Shibuya Takatoshi、Jiang Linhua
  • Journal Title: The Astrophysical Journal Volume: 856 Issue: 2 Pages: 109-109
  • DOI: 10.3847/1538-4357/aab35b
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] SPLASH-SXDF Multi-wavelength Photometric Catalog (2018)
  • Author(s): Mehta Vihang、incl. Takatoshi Shibuya
  • Journal Title: The Astrophysical Journal Supplement Series Volume: 235 Issue: 2 Pages: 36-36
  • DOI: 10.3847/1538-4365/aab60c
  • Peer Reviewed
• [Journal Article] Similarities and uniqueness of Ly α emitters among star-forming galaxies at z = 2.5 (2017)
  • Author(s): Shimakawa, Rhythm; Kodama, Tadayuki; Shibuya, Takatoshi; Kashikawa, Nobunari; Tanaka, Ichi; Matsuda, Yuichi; Tadaki, Ken-ichi; Koyama, Yusei; Hayashi, Masao; Suzuki, Tomoko L.; Yamamoto, Moegi
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 468 Pages: 1123-1141
  • DOI: 10.1093/mnras/stx091
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Direct evidence for Lyboldsymbol{alpha } depletion in the protocluster core (2017)
  • Author(s): Shimakawa, Rhythm; Kodama, Tadayuki; Hayashi, Masao; Tanaka, Ichi; Matsuda, Yuichi; Kashikawa, Nobunari; Shibuya, Takatoshi; Tadaki, Ken-ichi; Koyama, Yusei; Suzuki, Tomoko L.; Yamamoto, Moegi
  • Journal Title: Monthly Notices of the Royal Astronomical Society: Letters Volume: 468 Issue: 1 Pages: 21-25
  • DOI: 10.1093/mnrasl/slx019
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Evolution of N/O abundance ratios and ionization parameters from z~0 to 2 investigated by the direct temperature method (2017)
  • Author(s): Kojima Takashi、Ouchi Masami、Nakajima Kimihiko、et al.
  • Journal Title: PASJ Volume: 69 Issue: 3 Pages: 1-21
  • DOI: 10.1093/pasj/psx017
  • Peer Reviewed
• [Journal Article] A New Constraint on Reionization from the Evolution of the Lyα Luminosity Function at z~6-7 Probed by a Deep Census of z = 7.0 Lyα Emitter Candidates to 0.3L (2017)
  • Author(s): Ota, Kazuaki; Iye, Masanori; Kashikawa, Nobunari; Konno, Akira; Nakata, Fumiaki; Totani, Tomonori; Kobayashi, Masakazu A. R.; Fudamoto, Yoshinobu; Seko, Akifumi; Toshikawa, Jun; Ichikawa, Akie; Shibuya, Takatoshi; Onoue, Masafusa
  • Journal Title: The Astrophysical Journal Volume: 844 Issue: 1 Pages: 85-122
  • DOI: 10.3847/1538-4357/aa7a0a
  • Peer Reviewed
• [Journal Article] Evolution of Galactic Outflows at z~0-2 Revealed with SDSS, DEEP2, and Keck Spectra (2017)
  • Author(s): Sugahara Yuma、Ouchi Masami、Lin Lihwai、et al.
  • Journal Title: ApJ Volume: 850 Issue: 1 Pages: 51-51
  • DOI: 10.3847/1538-4357/aa956d
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Demonstrating a New Census of Infrared Galaxies with ALMA (DANCING-ALMA). I. FIR Size and Luminosity Relation at z = 0?6 Revealed with 1034 ALMA Sources (2017)
  • Author(s): Fujimoto Seiji、Ouchi Masami、Shibuya Takatoshi、Nagai Hiroshi
  • Journal Title: The Astrophysical Journal Volume: 850 Issue: 1 Pages: 83-83
  • DOI: 10.3847/1538-4357/aa93e6
  • Peer Reviewed
• [Journal Article] GOLDRUSH. II. Clustering of galaxies at z~4-6 revealed with the half-million dropouts over the 100 deg2 area corresponding to 1 Gpc3 (2017)
  • Author(s): Harikane Yuichi、Ouchi Masami、Ono Yoshiaki、Saito Shun、Behroozi Peter、More Surhud、Shimasaku Kazuhiro、Toshikawa Jun、Lin Yen-Ting、Akiyama Masayuki、Coupon Jean、Komiyama Yutaka、Konno Akira、Lin Sheng-Chieh、Miyazaki Satoshi、Nishizawa Atsushi J、Shibuya Takatoshi、Silverman John
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-27
  • DOI: 10.1093/pasj/psx097
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] SILVERRUSH. II. First catalogs and properties of ~2000 Lyα emitters and blobs at z~6-7 identified over the 14-21 deg2 sky (2017)
  • Author(s): Shibuya Takatoshi、Ouchi Masami、Konno Akira、Higuchi Ryo、Harikane Yuichi、Ono Yoshiaki、Shimasaku Kazuhiro、Taniguchi Yoshiaki、Kobayashi Masakazu A R、Kajisawa Masaru、Nagao Tohru、Furusawa Hisanori、Goto Tomotsugu、Kashikawa Nobunari、Komiyama Yutaka、Kusakabe Haruka、Lee Chien-Hsiu、Momose Rieko、et al.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-20
  • DOI: 10.1093/pasj/psx122
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] SILVERRUSH. III. Deep optical and near-infrared spectroscopy for Lyα and UV-nebular lines of bright Lyα emitters at z=6-7 (2017)
  • Author(s): Shibuya Takatoshi、Ouchi Masami、Harikane Yuichi、Rauch Michael、Ono Yoshiaki、Mukae Shiro、Higuchi Ryo、Kojima Takashi、Yuma Suraphong、Lee Chien-Hsiu、Furusawa Hisanori、Konno Akira、Martin Crystal L、Shimasaku Kazuhiro、Taniguchi Yoshiaki、Kobayashi Masakazu A R、Kajisawa Masaru、Nagao Tohru、et al.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-23
  • DOI: 10.1093/pasj/psx107
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] A 16 deg^2 survey of emission-line galaxies at z<1.5 in HSC-SSP Public Data Release 1 (2017)
  • Author(s): Hayashi Masao、Tanaka Masayuki、Shimakawa Rhythm、Furusawa Hisanori、Momose Rieko、Koyama Yusei、Silverman John D、Kodama Tadayuki、Komiyama Yutaka、Leauthaud Alexie、Lin Yen-Ting、Miyazaki Satoshi、Nagao Tohru、Nishizawa Atsushi J、Ouchi Masami、Shibuya Takatoshi、Tadaki Ken-ichi、Yabe Kiyoto
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 17-17
  • DOI: 10.1093/pasj/psx088
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] SILVERRUSH. IV. Lyα luminosity functions at z=5.7 and 6.6 studied with ~1300 Lyα emitters on the 14-21 deg2 sky (2017)
  • Author(s): Konno Akira、Ouchi Masami、Shibuya Takatoshi、Ono Yoshiaki、Shimasaku Kazuhiro、Taniguchi Yoshiaki、Nagao Tohru、Kobayashi Masakazu A R、Kajisawa Masaru、Kashikawa Nobunari、Inoue Akio K、Oguri Masamune、Furusawa Hisanori、Goto Tomotsugu、Harikane Yuichi、Higuchi Ryo、Komiyama Yutaka、et al.
  • Journal Title: Publications of the Astronomical Society of Japan Volume: 70 Issue: SP1 Pages: 1-21
  • DOI: 10.1093/pasj/psx131
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Cosmic Galaxy-IGM HI Relation at z~2-3 Probed in the COSMOS/UltraVISTA 1.6 Deg^2 Field (2017)
  • Author(s): Mukae, Ouchi et al.
  • Journal Title: The Astrophysical Journal Volume: 835 Issue: 2 Pages: 281-292
  • DOI: 10.3847/1538-4357/835/2/281
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Lya emitters with very large Lyα equivalent widths, EW0(Lya)~=200-400A, at z~2 (2017)
  • Author(s): Hashimoto, Ouchi et al.
  • Journal Title: Monthly Notices of the Royal Astronomical Society Volume: 465 Issue: 2 Pages: 1543-1562
  • DOI: 10.1093/mnras/stw2834
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Morphologies of ~190,000 Galaxies at z=0-10 Revealed with HST Legacy Data. III. Evolution of Clumpy Galaxies (2016)
  • Author(s): Shibuya, Ouchi, Kubo & Harikane
  • Journal Title: The Astrophysical Journal Volume: 821 Issue: 2 Pages: 72-90
  • DOI: 10.3847/0004-637x/821/2/72
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] EVOLUTION OF STELLAR-TO-HALO MASS RATIO AT z=0-7 IDENTIFIED BY CLUSTERING ANALYSIS WITH THE HUBBLE LEGACY IMAGING AND EARLY SUBARU/HYPER SUPRIME-CAM SURVEY DATA (2016)
  • Author(s): Harikane, Ouchi et al.
  • Journal Title: The Astrophysical Journal Volume: 821 Issue: 2 Pages: 123-145
  • DOI: 10.3847/0004-637x/821/2/123
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Detection of an oxygen emission line from a high-redshift galaxy in the reionization epoch (2016)
  • Author(s): Inoue, Akio K.; Tamura, Yoichi; Matsuo, Hiroshi; Mawatari, Ken; Shimizu, Ikkoh; Shibuya, Takatoshi; Ota, Kazuaki; Yoshida, Naoki; Zackrisson, Erik; Kashikawa, Nobunari; Kohno, Kotaro; Umehata, Hideki; Hatsukade, Bunyo; Iye, Masanori; Matsuda, Yuichi; Okamoto, Takashi; Yamaguchi, Yuki
  • Journal Title: Science Volume: 325 Issue: 6293 Pages: 1559-1562
  • DOI: 10.1126/science.aaf0714
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] First Demographics of Very Bright Lyα Emitters at z~6－7 Uncovered by the Subaru HSC Narrowband Data (2017)
  • Author(s): 澁谷隆俊
  • Organizer: 日本天文学会 春季学会
  • Place of Presentation: 九州大学
• [Presentation] First demographics of very bright LAEs at z~6-7 uncovered by the large area Subaru HSC NB imaging and deep spectroscopy (2017)
  • Author(s): 澁谷隆俊
  • Organizer: すばる-ケック連携のためのワークショップ
  • Place of Presentation: 国立天文台
• [Presentation] First demographics of very bright LAEs at z~6-7 uncovered by the large area Subaru HSC NB imaging and deep spectroscopy (2016)
  • Author(s): T. Shibuya, HSC Project 84, 85, and 197 Members
  • Organizer: Panoramas of the Evolving Cosmos
  • Place of Presentation: International Conference Center Hiroshima
  • Year and Date: 2016-11-28
  • Int'l Joint Research
• [Presentation] Studies of Lya Emitters (2016)
  • Author(s): T. Shibuya, HSC Project 84, 85, and 197 Members
  • Organizer: HSC collaboration meeting
  • Place of Presentation: IPMU
  • Int'l Joint Research