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Revealing chemical reactions in high-mass star-forming regions with observations, laboratory experiments, and chemical network simulations

Research Project

Project/Area Number 20K14523
Research Category

Grant-in-Aid for Early-Career Scientists

Allocation TypeMulti-year Fund
Review Section Basic Section 16010:Astronomy-related
Research InstitutionNational Astronomical Observatory of Japan (2021-2023)
Gakushuin University (2020)

Principal Investigator

TANIGUCHI Kotomi  国立天文台, 科学研究部, 特任助教 (40865549)

Project Period (FY) 2020-04-01 – 2024-03-31
Project Status Completed (Fiscal Year 2023)
Budget Amount *help
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2023: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2022: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2021: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2020: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords星間化学 / 電波天文学 / 星形成 / 電波天文観測 / 天文学
Outline of Research at the Start

大質量星は銀河の進化や太陽系の形成過程を理解する上で重要だが、その形成過程の研究は中小質量星に比べて遅れている。大質量星周辺のガスの化学組成には天体毎に異なる特徴があると発見され、それは大質量星の形成過程を解明する手がかりとなり得ることがわかってきた。本研究では、この大質量星形成領域における化学的多様性の起源及び大質量星形成過程について、電波天文学的観測手法、室内実験、化学反応ネットワークシミュレーションの3つを統合的に駆使して解明することを目的とする。

Outline of Final Research Achievements

I have studies formation and destruction mechanisms of carbon-chain molecules around massive young stellar objects by observations using ALMA and chemical network simulations. Cyanodiacetylene (HC5N), one of the carbon-chain species, has been detected from three massive young stellar objects among five target sources. I have confirmed that HC5N emission comes from hot regions with temperatures above 100 K combining with the chemical network simulations. The formation process of carbon-chain species around massive stars is different from that around low-mass protostars, Warm Carbon-Chain Chemistry (WCCC). I have proposed Hot Carbon-Chain Chemistry to explain the observed abundances of HC5N around massive stars, and shown chemical diversity around massive young stellar objects.

Academic Significance and Societal Importance of the Research Achievements

原始星周囲の炭素鎖分子の生成・破壊メカニズムや化学的多様性については、太陽系近傍の低質量星形成領域のみで進められてきた。本研究で、大質量星原始星周囲での独自の炭素鎖分子の生成メカニズムの発見と化学的多様性の発見は世界でも初めての成果である。また、大質量星形成領域での研究が進んだことで、幅広い温度や密度などの物理パラメータと化学組成の比較が可能になり、原始星周囲の物理と化学の関係について研究が進められるようになった。

Report

(5 results)
  • 2023 Annual Research Report   Final Research Report ( PDF )
  • 2022 Research-status Report
  • 2021 Research-status Report
  • 2020 Research-status Report
  • Research Products

    (55 results)

All 2024 2023 2022 2021 2020 Other

All Int'l Joint Research (15 results) Journal Article (13 results) (of which Int'l Joint Research: 12 results,  Peer Reviewed: 13 results,  Open Access: 10 results) Presentation (23 results) (of which Int'l Joint Research: 11 results,  Invited: 6 results) Remarks (4 results)

  • [Int'l Joint Research] Instituto Nacional de Astrofisica(メキシコ)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] University of Virginia/University of Massachusetts(米国)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] MPE(ドイツ)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] NISER(インド)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] Chalmers University of Technology(スウェーデン)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] University of Virginia(米国)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] MPE(ドイツ)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] NISER(インド)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] Chalmers University of Technology(スウェーデン)

    • Related Report
      2022 Research-status Report
  • [Int'l Joint Research] University of Virginia/NRAO/NASA/JPL(米国)

    • Related Report
      2021 Research-status Report
  • [Int'l Joint Research] NISER(インド)

    • Related Report
      2021 Research-status Report
  • [Int'l Joint Research] University of Virginia/NASA JPL(米国)

    • Related Report
      2020 Research-status Report
  • [Int'l Joint Research] Max-Planck-Institute(ドイツ)

    • Related Report
      2020 Research-status Report
  • [Int'l Joint Research] NISER(インド)

    • Related Report
      2020 Research-status Report
  • [Int'l Joint Research] Chalmers University of Technology(スウェーデン)

    • Related Report
      2020 Research-status Report
  • [Journal Article] Observations of high-order multiplicity in a high-mass stellar protocluster2024

    • Author(s)
      Li Shanghuo、Sanhueza Patricio、Beuther Henrik、Chen Huei-Ru Vivien、Kuiper Rolf、Olguin Fernando A.、Pudritz Ralph E.、Stephens Ian W.、Zhang Qizhou、Nakamura Fumitaka、Lu Xing、Kuruwita Rajika L.、Sakai Takeshi、Henning Thomas、Taniguchi Kotomi、Li Fei
    • Journal Title

      Nature Astronomy

      Volume: 15 Issue: 4 Pages: 1-18

    • DOI

      10.1038/s41550-023-02181-9

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Large-scale Mapping Observations of DCN and DCO<sup>+</sup> toward Orion KL2024

    • Author(s)
      Kotomi Taniguchi, Prathap Rayalacheruvu, Teppei Yonetsu et al.
    • Journal Title

      The Astrophysical Journal

      Volume: 963 Issue: 1 Pages: 12-12

    • DOI

      10.3847/1538-4357/ad1e5a

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] An Extremely Young Protostellar Core, MMS 1/OMC-3: Episodic Mass Ejection History Traced by the Micro SiO Jet2024

    • Author(s)
      Takahashi Satoko、Machida Masahiro N.、Omura Mitsuki、Johnstone Doug、Saigo Kazuya、Harada Naoto、Tomisaka Kohji、Ho Paul T. P.、Zapata Luis A.、Mairs Steve、Herczeg Gregory J.、Taniguchi Kotomi、Liu Yuhua、Sato Asako
    • Journal Title

      The Astrophysical Journal

      Volume: 964 Issue: 1 Pages: 48-48

    • DOI

      10.3847/1538-4357/ad2268

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Digging into the Interior of Hot Cores with the ALMA (DIHCA). III. The Chemical Link between NH2CHO, HNCO, and H2CO2023

    • Author(s)
      Taniguchi Kotomi、Sanhueza Patricio、Olguin Fernando A.、Gorai Prasanta、Das Ankan、Nakamura Fumitaka、Saito Masao、Zhang Qizhou、Lu Xing、Li Shanghuo、Chen Huei-Ru Vivien
    • Journal Title

      The Astrophysical Journal

      Volume: 950 Issue: 1 Pages: 57-57

    • DOI

      10.3847/1538-4357/acca1d

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Chemical Differentiation around Five Massive Protostars Revealed by ALMA: Carbon-chain Species and Oxygen/Nitrogen-bearing Complex Organic Molecules2023

    • Author(s)
      Taniguchi Kotomi、Majumdar Liton、Caselli Paola、Takakuwa Shigehisa、Hsieh Tien-Hao、Saito Masao、Li Zhi-Yun、Dobashi Kazuhito、Shimoikura Tomomi、Nakamura Fumitaka、Tan Jonathan C.、Herbst Eric
    • Journal Title

      The Astrophysical Journal Supplement Series

      Volume: 267 Issue: 1 Pages: 4-4

    • DOI

      10.3847/1538-4365/acd110

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Digging into the Interior of Hot Cores with ALMA: Spiral Accretion into the High-mass Protostellar Core G336.01?0.822023

    • Author(s)
      Olguin Fernando A.、Sanhueza Patricio、Chen Huei-Ru Vivien、Lu Xing、Oya Yoko、Zhang Qizhou、Ginsburg Adam、Taniguchi Kotomi、Li Shanghuo、Morii Kaho、Sakai Takeshi、Nakamura Fumitaka
    • Journal Title

      The Astrophysical Journal Letters

      Volume: 959 Issue: 2 Pages: L31-L31

    • DOI

      10.3847/2041-8213/ad1100

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Vibrationally Excited Lines of HC3N Associated with the Molecular Disk around the G24.78+0.08 A1 Hypercompact H ii Region2022

    • Author(s)
      Taniguchi Kotomi、Tanaka Kei E. I.、Zhang Yichen、Fedriani Ruben、Tan Jonathan C.、Takakuwa Shigehisa、Nakamura Fumitaka、Saito Masao、Majumdar Liton、Herbst Eric
    • Journal Title

      The Astrophysical Journal

      Volume: 931 Issue: 2 Pages: 99-99

    • DOI

      10.3847/1538-4357/ac69d1

    • Related Report
      2022 Research-status Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Carbon-chain Chemistry versus Complex-organic-molecule Chemistry in Envelopes around Three Low-mass Young Stellar Objects in the Perseus Region2021

    • Author(s)
      Taniguchi Kotomi、Majumdar Liton、Takakuwa Shigehisa、Saito Masao、Lis Dariusz C.、Goldsmith Paul F.、Herbst Eric
    • Journal Title

      The Astrophysical Journal

      Volume: 910 Issue: 2 Pages: 141-141

    • DOI

      10.3847/1538-4357/abe854

    • Related Report
      2021 Research-status Report 2020 Research-status Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Chemical Compositions in the Vicinity of Protostars in Ophiuchus2021

    • Author(s)
      Taniguchi Kotomi、Majumdar Liton、Plunkett Adele、Takakuwa Shigehisa、Lis Dariusz C.、Goldsmith Paul F.、Nakamura Fumitaka、Saito Masao、Herbst Eric
    • Journal Title

      The Astrophysical Journal

      Volume: 922 Issue: 2 Pages: 152-152

    • DOI

      10.3847/1538-4357/ac214e

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Optical Properties of Interstellar Dust around the Orion A Molecular Cloud2021

    • Author(s)
      Hayato Uehara, Kazuhito Dobashi, Shingo Nishiura, Tomomi Shimoikura, and Takahiro Naoi
    • Journal Title

      The Astrophysical Journal

      Volume: 915 Issue: 6 Pages: 1540-1555

    • DOI

      10.1093/pasj/psab092

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] 13C Isotopic Ratios of HC3N on Titan Measured with ALMA2021

    • Author(s)
      Iino Takahiro、Taniguchi Kotomi、Sagawa Hideo、Tsukagoshi Takashi
    • Journal Title

      The Planetary Science Journal

      Volume: 2 Issue: 4 Pages: 166-166

    • DOI

      10.3847/psj/ac134c

    • Related Report
      2021 Research-status Report
    • Peer Reviewed / Open Access
  • [Journal Article] Carbon Chain Chemistry in Hot-core Regions around Three Massive Young Stellar Objects Associated with 6.7 GHz Methanol Masers2021

    • Author(s)
      Taniguchi Kotomi、Herbst Eric、Majumdar Liton、Caselli Paola、Tan Jonathan C.、Li Zhi-Yun、Shimoikura Tomomi、Dobashi Kazuhito、Nakamura Fumitaka、Saito Masao
    • Journal Title

      The Astrophysical Journal

      Volume: 908 Issue: 1 Pages: 100-100

    • DOI

      10.3847/1538-4357/abd6c9

    • Related Report
      2020 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Chemical Composition in the IRAS 16562-3959 High-mass Star-forming Region2020

    • Author(s)
      Taniguchi Kotomi、Guzman Andres E.、Majumdar Liton、Saito Masao、Tokuda Kazuki
    • Journal Title

      The Astrophysical Journal

      Volume: 898 Issue: 1 Pages: 54-54

    • DOI

      10.3847/1538-4357/ab994d

    • Related Report
      2020 Research-status Report
    • Peer Reviewed / Int'l Joint Research
  • [Presentation] LMT 2millimeter receiver system (B4R): Overview and results of demo-science2023

    • Author(s)
      Kotomi Taniguchi, Ryohei Kawabe, Takeshi Sakai, Bunyo Hatsukade, Kunihiko Tanaka, Akio Taniguchi, Yuki Yoshimura, Tatsuya Takekoshi, Teppei Yonetsu, Masato Hagimoto, Hiroyuki Maezawa, Yoichi Tamura, Kotaro Kohno, David H. Hughes, F. Peter Schloerb, and B4R/LMT Collaboration
    • Organizer
      URSI GASS 2023
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Chemical Link among NH2CHO, HNCO, H2CO in High-Mass Protostellar Cores2023

    • Author(s)
      Kotomi Taniguchi, Patricio Sanhueza, Fernando A. Olguin, Prasanta Gorai, Ankan Das, Fumitaka Nakamura, Masao Saito, Qizhou Zhang, Xing Lu, Shanghuo Li, Huei-Ru Vivien Chen
    • Organizer
      Astrochemistry Symposium
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Understanding Chemical Differentiation around Five Massive Protostars Revealed by ALMA2023

    • Author(s)
      Kotomi Taniguchi, Liton Majumdar, Paola Caselli, Shigehisa Takakuwa, Masao Saito, Kazuhito Dobashi, Fumitaka Nakamura, Tomomi Shimoikura, Tien-Hao Hsieh, Jonathan C. Tan, Zhi-Yun Li, Eric Herbst
    • Organizer
      Planets VII
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Q-band line survey observations toward 12 intermediate-mass protostars with the Yebes 40m telescope2023

    • Author(s)
      Kotomi Taniguchi, Prasanta Gorai, Jonathan C. Tan, Miguel Gomez Garrido, Masao Saito, Fumitaka Nakamura, T. K. Sridharan, & SOFIA Massive Star Formation group
    • Organizer
      日本天文学会秋季大会
    • Related Report
      2023 Annual Research Report
  • [Presentation] Revealing the Chemical Link among NH2CHO, HNCO, and H2CO using ALMA Observations toward High-Mass Protostellar Cores2023

    • Author(s)
      Kotomi Taniguchi, Patricio Sanhueza, Fernando A. Olguin, Prasanta Gorai, Ankan Das, Fumitaka Nakamura, Masao Saito
    • Organizer
      East-Asia ALMA Science Workshop 2023
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] 30-34 GHz Line Survey Observations toward the Serpens South with the eQ Receiver2023

    • Author(s)
      Kotomi Taniguchi, Fumitaka Nakamura, Ryohei Kawabe, Ross Burns, Atsushi Nishimura, Chau-Ching Chiong, Sheng-Yuan Liu, You-Ting Yeh, Shih-Ping Lai, Tomomi Shimoikura, Kazuhito Dobashi, Yoshinori Yonekura, Yasumasa Yamasaki, & eQ-receiver team
    • Organizer
      宇宙電波懇談会シンポジウム2022
    • Related Report
      2022 Research-status Report
  • [Presentation] Survey of NH2CHO, HNCO, H2CO, and CH3CN toward high-mass protostars by the DIHCA Project2023

    • Author(s)
      Kotomi Taniguchi, Patricio Sanhueza, Fernando A. Olguin, Prasanta Gorai, Ankan Das, Fumitaka Nakamura, Masao Saito
    • Organizer
      日本天文学会 春季大会
    • Related Report
      2022 Research-status Report
  • [Presentation] Carbon-Chain Chemistry around Massive Young Stellar Objects2022

    • Author(s)
      Kotomi Taniguchi
    • Organizer
      Dust-Ice-Gas (DIG) Astrochemistry
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Understanding Chemical Diversity around Massive Young Stellar Objects2022

    • Author(s)
      Kotomi Taniguchi, Liton Majumdar, Paola Caselli, Shigehisa Takakuwa, Masao Saito, Kazuhito Dobashi, Fumitaka Nakamura, Tomomi Shimoikura, Tien-Hao Hsieh, Jonathan C. Tan, Zhi-Yun Li, & Eric Herbst
    • Organizer
      From Clouds to Planets II: The Astrochemical Link
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research
  • [Presentation] Observational Evidence for Cyanopolyyne Chemistry and Chemical Diversity around Massive Young Stellar Objects2022

    • Author(s)
      Kotomi Taniguchi
    • Organizer
      VICO-CICO Workshop 2022
    • Related Report
      2022 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Observational Evidence for Cyanopolyyne Chemistry around High-Mass Stars2022

    • Author(s)
      Kotomi Taniguchi, Liton Majumdar, Paola Caselli, Tien-Hao Hsieh, Shigehisa Takakuwa, Masao Saito, Fumitaka Nakamura, Kazuhito Dobashi, Tomomi Shimoikura, Jonathan C. Tan, Zhi-Yun Li, Eric Herbst
    • Organizer
      日本天文学会 秋季大会
    • Related Report
      2022 Research-status Report
  • [Presentation] Chemical Survey Observations toward Intermediate-Mass Protostars2022

    • Author(s)
      Kotomi Taniguchi, Miguel Gomez Garrido, Prasanta Gorai, Jonathan C. Tan, Masao Saito, Fumitaka Nakamura, T. K. Sridharan, Liton Majumdar, & SOFIA Massive Star Formation group
    • Organizer
      日本天文学会 秋季大会
    • Related Report
      2022 Research-status Report
  • [Presentation] Vibrationally-excited Lines of HC3N Tracing the Disk Structure around the G24.78+0.08 A1 Hyper-compact HII Region2022

    • Author(s)
      谷口琴美、田中圭、Yichen Zhang、Ruben Fedriani、 Jonathan C. Tan、高桑繁久、中村文隆、齋藤正雄、Liton Majumdar、Eric Herbst
    • Organizer
      日本天文学会2022年春季大会
    • Related Report
      2021 Research-status Report
  • [Presentation] 星形成領域における化学プロセスの多様性 -星質量・物理環境との関係-2022

    • Author(s)
      谷口琴美
    • Organizer
      宇宙電波懇談会シンポジウム2021
    • Related Report
      2021 Research-status Report
    • Invited
  • [Presentation] Roles of UV radiation on the chemistry of protostars in the Ophiuchus region2021

    • Author(s)
      Kotomi Taniguchi, Liton Majumdar, Adele Plunkett, Shigehisa Takakuwa, Dariusz C. Liz, Paul F. Goldsmith, Fumitaka Nakamura, Masao Saito, Eric Herbst
    • Organizer
      Astrochemical Frontiers 2021
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research
  • [Presentation] Nitrile chemistry in a disk structure around the G24.78+0.08 hyper-compact HII region2021

    • Author(s)
      Kotomi Taniguchi, Kei Tanaka, Y. Zhang, R. Fedriani, J. C. Tan, S. Takakuwa, F. Nakamura, M. Saito, L. Majumdar, E. Herbst
    • Organizer
      Workshop on Interstellar Matter 2021
    • Related Report
      2021 Research-status Report
    • Int'l Joint Research
  • [Presentation] Investigation of roles of the UV radiation on the chemistry around protostars in the Ophiuchus region2021

    • Author(s)
      谷口琴美、中村文隆、齋藤正雄、Liton Majumdar, Adele Plunkett, 高桑繁久、Dariusz C. Liz, Paul F. Goldsmith, Eric Herbst
    • Organizer
      日本天文学会2021年秋季大会
    • Related Report
      2021 Research-status Report
  • [Presentation] A New Type of Carbon Chain Chemistry around Massive Young Stellar Objects2021

    • Author(s)
      Kotomi Taniguchi
    • Organizer
      Nobeyama Science Workshop 2020
    • Related Report
      2020 Research-status Report
    • Invited
  • [Presentation] ALMA observations of CH3OH and HC3N toward three low-mass young stellar objects in the Perseus region2021

    • Author(s)
      Kotomi Taniguchi, Liton Majumdar, Shigehisa Takakuwa, Masao Saito, Dariusz C. Liz, Paul F. Goldsmith, Eric Herbst
    • Organizer
      日本天文学会 春季大会
    • Related Report
      2020 Research-status Report
  • [Presentation] Carbon Chain Chemistry in Hot-Core Regions around Massive Young Stellar Objects2020

    • Author(s)
      Kotomi Taniguchi
    • Organizer
      VICO-CICO Workshop 2020
    • Related Report
      2020 Research-status Report
    • Int'l Joint Research / Invited
  • [Presentation] Chemical composition in the IRAS 16562-3959 high-mass star-forming region2020

    • Author(s)
      Kotomi Taniguchi, Andres Guzman, Liton Majumdar, Masao Saito, Tokuda Kazuki
    • Organizer
      43rd COSPAR Scientific Assembly 2020
    • Related Report
      2020 Research-status Report
    • Int'l Joint Research
  • [Presentation] 星間ダスト表面における光化学反応実験のための装置の立ち上げと初期成果2020

    • Author(s)
      谷口琴美、平山朱実、久保崇紀、荒川一郎、山川紘一郎
    • Organizer
      日本天文学会 秋季大会
    • Related Report
      2020 Research-status Report
  • [Presentation] 紫外線照射下における一酸化炭素の水素付加反応に関する室内実験2020

    • Author(s)
      平山朱実、久保崇紀、永井颯真、谷口琴美、山川紘一郎
    • Organizer
      Nobeyama Science Workshop 2020
    • Related Report
      2020 Research-status Report
  • [Remarks] Reveal chemical links involving NH2CHO

    • URL

      https://sci.nao.ac.jp/main/highlights/20230414

    • Related Report
      2023 Annual Research Report
  • [Remarks] Discovery of a new type of carbon-chain chemistry

    • URL

      https://sci.nao.ac.jp/main/highlights/20230515

    • Related Report
      2023 Annual Research Report
  • [Remarks] 大質量星が誕生している領域の化学組成と星の進化の過程 -分子で探る重い星が生まれる環境-

    • URL

      https://www.univ.gakushuin.ac.jp/about/pr/press/20200723release.html

    • Related Report
      2020 Research-status Report
  • [Remarks] 大質量星に照らされた天空のカーボン・チェーン工場;高温領域で形成される「炭素鎖分子」の発見

    • URL

      https://www.nro.nao.ac.jp/news/2021/0224-taniguchi.html#nmnews

    • Related Report
      2020 Research-status Report

URL: 

Published: 2020-04-28   Modified: 2025-01-30  

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