Refereed Journals

2024


1. "Investigating the impact of X-ray computed tomography imaging on soluble organic matter in the Murchison meteorite: Implications for Bennu sample analysis"
   D. P. Glavin, S. A. Eckley, J. C. Aponte, E. L. Berger, A. S. Burton, J. P. Dworkin, J. E. Elsila, F. T. Ferguson, Y. Furukawa, H. V. Graham, T. Koga, M. Liss, H. L. McLain, H. Naraoka, Y. Oba, E. T. Parker, K. Righter, P. Schmitt-Kopplin, D. N. Simkus, Y. Takano, H. C. Connolly Jr., D. S. Lauretta
   Meteoritics and Planetary Science, 59, 105-133 (2024).
   
   
2. "Abundant extraterrestrial purine nucleobases in the Murchison meteorite: Implications for a unified mechanism for purine synthesis in carbonaceous chondrite parent bodies"
   T. Koga, Y. Takano, N. O. Ogawa, Y. Oba, H. Naraoka, N. Ohkouchi
   Geochimica et Cosmochimica Acta, 365, 253-265 (2024).
   
   2023
   
   
3. "Polycyclic aromatic hydrocarbons in samples of Ryugu formed in the interstellar medium"
   Sarah Zeichner, Jose C. Aponte, Surjyendu Bhattacharjee, Guannan Dong, Amy E. Hofmann, Jason P. Dworkin, Daniel P. Glavin, Jamie E. Elsila, Heather V. Graham, Hiroshi Naraoka, Yoshinori Takano, Shogo Tachibana, Allison T. Karp, Kliti Grice, Alex I. Holman, Katherine H. Freeman, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Kanako Sakamoto, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Satoru Nakazawa, Sei-ichiro Watanabe, Yuichi Tsuda, Kenji Hamase, Kazuhiko Fukushima, Dan Aoki, Minako Hashiguchi, Hajime Mita, Yoshito Chikaraishi, Naohiko Ohkouchi, Nanako O. Ogawa, Saburo Sakai, Eric T. Parker, Hannah L. McLain, Francois-Regis Orthous-Daunay, Veronique Vuitton, Roland Thissen, Cedric Wolters, Philippe Schmitt-Kopplin, Alexander Ruf , Junko Isa, Norbert Hertkorn, Yasuhiro Oba, Toshiki Koga, Toshihiro Yoshimura, Daisuke Araoka, Haruna Sugahara, Aogu Furusho, Kazunori Sasaki, Hajime Sato, Yoshihiro Furukawa, Junken Aoki, Kuniyuki Kano, Shin-ichiro M. Nomura, Takaaki Yoshikawa, Satoru Tanaka, Mayu Morita, Morihiko Onose, Fumie Kabashima, Kosuke Fujishima, Tomoya Yamazaki, Yuki Kimura, John M. Eiler
   Science, 382, 1411-1416 (2023).
   
   
4. "Determination of the branching ratio of CH3OH + OH reaction on water ice surface at 10 K"
   A. Ishibashi, H. Hidaka, W. M. C. Sameera, Y. Oba, N. Watanabe
   Astrophysical Journal, 960, 90 (2023).
   
   
5. "Chemical evolution of primordial salts and organic sulfur molecules in the asteroid 162173 Ryugu"
   Toshihiro Yoshimura, Yoshinori Takano, Hiroshi Naraoka, Toshiki Koga, Daisuke Araoka, Nanako O. Ogawa, Philippe Schmitt-Kopplin, Norbert Hertkorn, Yasuhiro Oba, Jason P. Dworkin, José C. Aponte, Takaaki Yoshikawa, Satoru Tanaka, Naohiko Ohkouchi, Minako Hashiguchi, Hannah McLain, Eric T. Parker, Saburo Sakai, Mihoko Yamaguchi, Takahiro Suzuki, Tetsuya Yokoyama, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Kanako Sakamoto, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Satoru Nakazawa, Sei-ichiro Watanabe, Yuichi Tsuda, Shogo Tachibana, Hayabusa2 SOM team
   Nature Communications, 14, 5284 (2023)
   Press Release from JAMSTEC



6. "Ryugu asteroid sample return provides a natural laboratory for primordial chemical evolution"
   Yasuhiro Oba, Yoshinori Takano, Jason P. Dworkin, Hiroshi Naraoka
   Nature Communications, 14, 3107 (2023)
   *This is a Comment article directly commissioned by the Nature Communications editorial team
   
   
7. "Uracil in the carbonaceous asteroid (162173) Ryugu"
   Yasuhiro Oba, Toshiki Koga, Yoshinori Takano, Nanako O. Ogawa, Naohiko Ohkouchi, Daniel P. Glavin, Jason P. Dworkin, Hiroshi Naraoka, Shogo Tachibana, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Kanako Sakamoto, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tatsuaki Okada, Tomohiro Usui, Makoto Yoshikawa, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Satoru Nakazawa, Sei-ichiro Watanabe, Yuichi Tsuda, Hayabusa2-initial-analysis SOM team
   Nature Communications, 14, 1292 (2023)
   (This article was selected as "Editors' Highlights")
   Press Release from Hokkaido University
*This article is highlighted in "CNN" and many others


8. "A systematic mechanisttic survery on the reactions between OH radical and CH₃OH on ice"
   W. M. C. Sameera, A. P. Jayaweera, A. Ishibashi, H. Hidaka, Y. Oba, N. Watanabe
   Faraday Discussions, 245, 508-518 (2023)
   
   
9. "The spatial distribution of soluble organic matter and their relationship to minerals in the asteroid (162173) Ryugu"
   Minako Hashiguchi, Dan Aoki, Kazuhiko Fukushima, Hiroshi Naraoka, Yoshinori Takano, Jason P. Dworkin, Karin E. Dworkin, José C. Aponte, Jamie E. Elsila, John M. Eiler, Yoshihiro Furukawa, Aogu Furusho, Daniel P. Glavin, Heather V. Graham, Kenji Hamase, Norbert Hertkorn, Junko Isa, Toshiki Koga, Hannah L. McLain, Hajime Mita, Yasuhiro Oba, Nanako O. Ogawa, Naohiko Ohkouchi, Francois-Regis Orthous-Daunay, Eric T. Parker, Alexander Ruf, Saburo Sakai, Philippe Schmitt-Kopplin, Haruna Sugahara, Roland Thissen, Véronique Vuitton, Cédric Wolters, Toshihiro Yoshimura, Hisayoshi Yurimoto, Tomoki Nakamura, Takaaki Noguchi, Ryuji Okazaki, Hikaru Yabuta, Kanako Sakamoto, Shogo Tachibana, Toru Yada, Masahiro Nishimura, Aiko Nakato, Akiko Miyazaki, Kasumi Yogata, Masanao Abe, Tomohiro Usui, Takanao Saiki, Takanao Saiki, Fuyuto Terui, Nakazawa Satoru, Sei-ichiro Watanabe, Yuichi Tsuda,
   Earth, Planets, and Space, 75, Article Number 73 (25pp). (2023)
   
   
10. "Soluble organic molecules in samples of the carbonaceous asteroid (162173) Ryugu"
    H. Naraoka, Y. Takano, J. P. Dworkin, Y. Oba, K. Hamase, A. Furusho, N. O. Ogawa, M. Hashiguchi, K. Fukushima, D. Aoki, P. Schmitt-Kopplin, J. C. Aponte, E. T. Parker, D. P. Glavin, H. L. McLain, J. E. Elsila, H. V. Graham, J. M. Eiler, F.-R. Orthous-Daunay, C. Wolters, J. Issa, T. Koga, N. Ohkouchi, Y. Chikaraishi, H. Sugahara, H. Mita, Y. Furukawa, N. Hertkorn, A. Ruf, H. Yurimoto, T. Nakamura, T. Noguchi, R. Okazaki, H. Yabuta, K. Sakamoto, S. Tachibana, H. C. Connolly, Jr., D. S. Lauretta, M. Abe, T. Yada, M. Hshimura, K. Yogata, A.Nakato, M. Yoshitake, A. Suzuki, A. Miyazaki, S. Furuya, K.Hatakeda, H. Soejima, Y. Hitomi, K. Kumagai, T. Usui, T.Hayashi, D. Yamamoto, R. Fukai, K. Kitazato, S. Sugita, N. Namiki, M. Arakawa, H. Ikeda, M. Ishiguro, N. Hirata, K. Wada, Y. Ishihara, R. Noguchi, T. Morota, N. Sakatani, K. Matsumoto, H. Senshu, R. Honda, E. Tatsumi, Y. Yokota, C. Honda, T. Michikami, M. Matsuoka, A. Miura, H. Noda, T. Yamada, K. Yoshihara, K. Kawahara, M. Ozaki, Y.-i. Iijima, H. Yano, M. Hayakawa, T. Iwata, R. Tsukizaki, H. Sawada, S. Hosoda, K. Ogawa, C. Okamoto, N. Hirata, K. Shirai, Y. Shimaki, M. Yamada, T. Okada, Y. Yamamoto, H. Takeuchi, A. Fujii, Y. Takei, K. Yoshikawa, Y. Mimasu, G. Ono, N. Ogawa, S. Kikuchi, S. Nakazawa, F. Terui, S. Tanaka, T. Saiki, M. Yoshikawa, S.-i. Watanabe, Y. Tsuda
    Science, 379, eabn9033, (2023)
    press release (in Japanese)



11. "Surface reaction of methyl mercaptan (CH₃SH) with hydrogen atoms on amorphous solid water"
    Thanh Nguyen, Yasuhiro Oba, W. M. C. Sameera, Kenji Furuya, Akira Kouchi, Naoki Watanabe
    Astrophysical Journal, 944, 219 (2023)
    
    2022
    
    
12. "Maleimide Index: A paleo-redox index based on the fragmented fossile-chlorophylls obtained by chromic acid oxidation"
    Kenta Asahina, Satoshi Takahashi, Ryosuke Saito, Kunio Kaiho, Yasuhiro Oba
    RSC Advances, 12, 31061 (2022)
    
    
13. "Chemical and Physical Characterization of the Isolated Protostellar Source CB68: FAUST IV"
    Muneaki Imai, Yoko Oya, Brian Svoboda, Hauyu Baobab Liu, Bertrand Lefloch, Serena Viti, Yichen Zhang, Cecilia Ceccarelli, Claudio Codella, Claire J. Chandler, Nami Sakai, Yuri Aikawa, Felipe O. Alves, Nadia Balucani, Eleonora Bianchi, Mathilde Bouvier, Gemma Busquet, Paola Caselli, Emmanuel Caux, Steven Charnley, Spandan Choudhury, Nicolas Cuello, Marta De Simone, Francois Dulieu, Aurora Duráan, Lucy Evans, Cécile Favre, Davide Fedele, Siyi Feng, Francesco Fontani, Logan Francis, Tetsuya Hama, Tomoyuki Hanawa, Eric Herbst, Shingo Hirano, Tomoya Hirota, Andrea Isella, Izaskun Jímenez-Serra, Doug Johnstone, Claudine Kahane, Romane Le Gal, Laurent Loinard, Ana López-Sepulcre, Luke T. Maud, María José Maureira, Francois Menard, Seyma Mercimek, Anna Miotello, George Moellenbrock, Shoji Mori, Nadia M. Murillo, Riouhei Nakatani, Hideko Nomura, Yasuhiro Oba, Ross O’Donoghue, Satoshi Ohashi, Yuki Okoda, Juan Ospina-Zamudio, Jaime Pineda, Linda Podio, Albert Rimola, Takeshi Sakai, Dominique Segura-Cox, Yancy Shirley, Vianney Taquet, Leonardo Testi, Charlotte Vastel, Naoki Watanabe, Yoshimasa Watanabe, Arezu Witzel, Ci Xue, Bo Zhao, Satoshi Yamamoto
    Astrophysical Journal, 934, 70 (2022)
    
    
14. "FAUST V: Hot methanol in the [BHB2007] 11 protobinary system"
    C. Vastel, F. Alves, C. Ceccarelli, M. Bouvier, I. Jimenez-Serra, T. Sakai, P. Caselli, L. Evans, F. Fontani, R. Le Gal, C. J. Chandler, B. Svoboda, L. Maud, C. Codella, N. Sakai, A. Lopez-Sepulcre, G. Moellenbrock, Y. Aikawa, N. Balucani, E. Bianchi, G. Busquet, E. Caux, S. Charnley, N. Cuello, M. De Simone, F. Dulieu, A. Duran, D. Fedele, S. Feng, L. Francis, T. Hama, T. Hanawa, E. Herbst, T. Hirota, M. Imai, A. Isella, D. Johnstone, B. Lefloch, L. Loinard, M. Maureira, N. M. Murillo, S. Mercimek, S. Mori, F. Menard, A. Miotello, R. Nakatani, H. Nomura, Y. Oba, S. Ohashi, Y. Okoda, J. Ospina-Zamudio, Y. Oya, J. E. Pineda, L. Podio, A. Rimola, D. Segura Cox, Y. Shirley, L. Testi, S. Viti, N. Watanabe, Y. Watanabe, A. Witzel, C. Xue, Y. Zhang, B. Zhao, S. Yamamoto
    Astronomy & Astrophysics, 664, A171 (2022)
    
    
15. "Diffusion activation energy and desorption activation energy for astrochemically relevant species on water ice show no clear relation"
    Kenji Furuya, Tetsuya Hama, Yasuhiro Oba, Akira Kouchi, Naoki Watanabe, Yuri Aikawa
    The Astrophysical Journal Letters, 933, L16 (13pp) (2022)
    
    
    
16. "Quantum chemical modelling of the radical chemistry on ice surfaces: An integrated quantum chemical and experimental approach"
    W. M. C. Sameera, B. Senevirathne, T. Nguyen, Y. Oba, A. Ishibashi, M. Tsuge, H. Hidaka, N. Watanabe
    Frontiers in Astronomy and Space Sciences, 9, 890161 (2022)
    
    
17. Identifying the wide diversity of extraterrestrial purine and pyrimidine nucleobases in carbonaceous meteorites"
    Y. Oba, Y. Takano, Y. Furukawa, T. Koga, D. P. Glavin, J. P. Dworkin, H. Naraoka
    Nature Communications, 13, 2008 (2022)
    Featured in NASA Goddard Website
*This article is highlighted in "USA TODAY" and many others
This paper is selected as "Top 25 Earth, Environmental,and Planetary Sciences Articles of 2022" published in Nature Communications


18. "Hydrogen abstraction reactions in formic and thioformic acid isomers by hydrogen and deuterium atoms"
    G. Molpeceres, I. Jímenez-Serra, Y. Oba, T. Nguyen, N. Watanabe, J. García de la Concepción, B. Maté, R. Oliveira, J. Kästner
    Astronomy & Astrophysics, 663, A41 (2022)
    
    
19. "Quantifying the chemical desorption of H₂S and PH₃ from amorphous water ice surfaces"
    K. Furuya, Y. Oba, T. Shimonishi
    Astrophysical Journal, 926, 171 (17pp) (2022)
    
    
20. "Misaligned rotations of the envelope, outflow, and disks in the multiple protostellar system of VLA4 1623-2417: FAUST. III"
    Satoshi Ohashi, Claudio Codella, Nami Sakai, Claire J. Chandler, Cecilia Ceccarelli, Felipe Alves, Davide Fedele, Tomoyuki Hanawa, Aurora Durán, Cécile Favre, Ana López-Sepulcre, Laurent Loinard, Seyma Mercimek, Nadia M. Murillo, Linda Podio, Yichen Zhang, Yuri Aikawa, Nadia Balucani, Eleonora Bianchi, Mathilde Bouvier, Gemma Busquet, Paola Caselli, Emmanuel Caux, Steven Charnley, Spandan Choudhury, Nicolas Cuello, Marta De Simone, Francois Dulieu, Lucy Evans, Siyi Feng, Francesco Fontani, Logan Francis, Tetsuya Hama, Eric Herbst, Shingo Hirano, Tomoya Hirota, Muneaki Imai, Andrea Isella, Izaskun Jímenez-Serra, Doug Johnstone, Claudine Kahane, Romane Le Gal, Bertrand Lefloch, Luke T. Maud, Maria Jose Maureira, Francois Menard, Anna Miotello, George Moellenbrock, Shoji Mori, Riouhei Nakatani, Hideko Nomura, Yasuhiro Oba, Ross O'Donoghue, Yuki Okoda, Juan Ospina-Zamudio, Yoko Oya, Jaime Pineda, Albert Rimola, Takeshi Sakai, Dominique Segura-Cox, Yancy Shirley, Brian Svoboda, Vianney Taquet, Leonardo Testi, Charlotte Vastel, Serena Viti, Naoki Watanabe, Yoshimasa Watanabe, Arezu Witzel, Ci Xue, Bo Zhao and Satoshi Yamamoto
    Astrophysical Journal, 927, 54 (22pp) (2022)
    
    
    
21. "UV-Induced Formation of Ice XI Observed Using an Ultra-High Vacuum Cryogenic Transmission Electron Microscope and its Implications for Planetary Science"
    Akira Kouchi, Yuki Kimura, Kensei Kitajima, Hiroyasu Katsuno, Hiroshi Hidaka, Yasuhiro Oba, Masashi Tsuge, Tomoya Yamazaki, Kazuyuki Fujita, Tetsuya Hama, Yukihiro Takahashi, Shunichi Nakatsubo, Naoki Watanabe
    Frontiers in Chemistry, 9, 799851 (2021)
    
    
22. "Successive H-atom addition to solid OCS on compact amorphous solid water"
    T. Nguyen, Y. Oba, W. M. C. Sameera, A. Kouchi, N. Watanabe.
    Astrophysical Journal, 922, 146 (2021)
    
    
23. "Efficient formation pathway of methyl formate: The role of OH radicals on ice dust"
    A. Ishibashi, H. Hidaka, Y. Oba, A. Kouchi, N. Watanabe.
    Astrophysical Journal Letters, 921, L13 (9pp) (2021)
    
    
24. "Experimental and computational studies on the physico-chemical behavior of phosphine induced by reactions with H and D atoms on interstellar grains"
    T. Nguyen, Y. Oba, W. M. C. Sameera, A. Kouchi, N. Watanabe.
    Astrophysical Journal, 918, 73 (15pp) (2021)
    
    
25. "Transmission electron microscopy study of the morphology of ices composed of H₂O, CO₂, and CO on refractory grains"
    A. Kouchi, M. Tsuge, T. Hama, Y. Oba, S. Okuzumi, S.-i. Sirono, M. Momose, N. Nakatani, K. Furuya, T. Shimonishi, T. Yamazaki, H. Hidaka, Y. Kimura, K.-i. Murata, K. Fujita, S. Nakatsubo, S. Tachibana, N. Watanabe.
    Astrophysical Journal, 918, 45 (20pp) (2021)
    
    
26. "Formation of chiral CO polyhedral crystals on icy interstellar grains"
    A. Kouchi, M. Tsuge, T. Hama, H. Niinomi, N. Nakatani, T. Shimonishi, Y. Oba, Y. Kimura, S.-i. Sirono, S. Okuzumi, M. Momose, K. Furuya, N. Watanabe.
    Monthly Notices of the Royal Astronomical Society, 505, 1530-1542 (2021)
    
    
27. "Analytical development of seamless procedures on cation-exchange chromatography and ion-pair chromatography with high-precision mass spectrometry for short-chain peptides"
    Y. Takano, Y. Oba, S. Furota, H. Naraoka, N. Ogawa, T. M. Blattmann, N. Ohkouchi
    International Journal of Mass Spectrometry, 463, 116529 (2021)
    
    
28. "FAUST II. Discovery of a secondary outflow in IRAS 15398-3359: Variability in outflow direction during the earliest stage of star formation?"
    Y. Okoda, Y. Oya, L. Francis, D. Johnstone, S. Inutsuka, C. Ceccarelli, C. Codella, C. Chandler, N. Sakai, Y. Aikawa, F. Alves, N. Balucani, E. Bianchi, M. Bouvier, P. Caselli, E. Caux, S. Charnley, S. Choudhury,M. de Simone, F. Dulieu, A. Duran, L. Evans, C. Favre, D. Fedele, S. Feng, F. Fontani, T. Hama, T. Hanawa, E. Herbst, T. Hirota, M. Imai, A. Isella, I. Jimenez-Serra, C. Kahane, B. Lefloch, L. Loinard, A. Lopez-Sepulcre, L. T. Maud, M. J. Maureira, F. Menard, S. Mercimek, A. Miotello, G. Moellenbrock, S. Mori, N. M. Murillo, R. Nakatani, H. Nomura, Y. Oba, R. O'Donoghue, S. Ohashi, J. Ospina-Zamudio, J. Pineda, L. Podio, A. Rimola, T. Sakai, D. S. Cox, Y. Shirley, B. Svoboda, V. Taquet, L. Testi, C. Vastel, S. Viti, N. Watanabe, Y. Watanabe, A. Witzel, C. Xue, Y. Zhang, B. Zhao, S. Yamamoto
    Astrophysical Journal, 910, 11(13pp) (2021)
    
    2020
    
    
29. "Extraterrestrial hexamethylenetetramine in meteorites-a precursor of prebiotic chemistry in the inner solar system"
    Y. Oba, Y. Takano, H. Naraoka, Y. Furukawa, D. P. Glavin, J. P. Dworkin, S. Tachibana
    Nature Communications, 11, 6243 (2020)
    Press release "Key building block for organic melecules discovered in meteorites", Hokkaido University

*This article is highlighted in "Physics.Org" and many others


30. "Precometary organic matter: A hidden reservoir of water inside the snow line"
    H. Nakano, N. Hirakawa, Y. Matsubara, S. Yamashita, T. Okuchi, K. Asahina, R. Tanaka, N. Suzuki, H. Naraoka, Y. Takano, S. Tachibana, T. Hama, Y. Oba, Y. Kimura, N. Watanabe, & A. Kouchi
    Scientific Reports, 10, 7755 (2020)
    
    
    
31. "FAUST I. The hot corino at the heart of the prototypical Class I protostar L1551 IRS5"
    E. Bianchi, C. Chandler, C. Ceccarelli, C. Codella, N. Sakai, A. Lopez-Sepulcre, L. T. Maud, G. Moellenbrock, B. Svoboda, Y. Watanabe, T. Sakai, F. Menard, Y. Aikawa, F. Alves, N. Balucani, M. de Simone, F. Dulieu, A. Duran, L. Evans, C. Favre, D. Fedele, S. Feng, F. Fontani, L. Francis, T. Hama, T. Hanawa, E. Herbst, T. Hirota, M. Imai, A. Isella, I. Jimenez-Serra, D. Johnstone, C. Kahane, B. Lefloch, N. M. Murillo, R. Nakatani, H. Nomura, Y. Oba, S. Ohashi, Y. Okoda, J. Ospina-Zamudio, Y. Oya, J. Pineda, L. Podio, A. Rimola, D. S. Cox, Y. Shirley, V. Taquet, L. Testi, C. Vastel, S. Viti, N. Watanabe, A. Witzel, C. Xue, Y. Zhang, B. Zhao, & S. Yamamoto
    Monthly Notices of the Royal Astronomical Society Letters, 498, L87-L92 (2020).
    
    
    
32. "UV-ray irradiation never causes amorphization of crystalline CO₂: A transmission electron microscopy study"
    M. Tsuge, T. Nguyen, Y. Oba, T. Hama, A. Kouchi, and N. Watanabe
    Chemical Physics Letters, 760, 137999 (2020)
    
    
33. "An experimental study of chemical desorption for phosphine in interstellar ice"
    T. Nguyen, Y. Oba, A. Kouchi, and N. Watanabe
    Astrophysical Journal Letters, 898, L52 (6pp) (2020)
    
    2019
    
    
34. "Nucleobase synthesis in interstellar ices"
    Oba Y.,Takano Y., Naraoka H., Watanabe N. and Kouchi A.
    Nature Communications, 10, 4413 (2019)
    Press release "Life's building blocks may have formed in interstellar clouds", Hokkaido University

*This article is highlighted in "Fox News" and many others


35. "Physico-chemical behabior of hydrogen sulfide induced by reactions with H and D atoms on different types of ice surfaces at low temperature"
    Oba Y.,Tomaru T., Kouchi A. and Watanabe N.
    Astrophysical Journal, 874,124 (8pp) (2019)
    2018
    
    
36. "An infrared measurement of chemical desorption from interstellar ice analogues"
    Oba Y.,Tomaru T., Lamberts T., Kouchi A. and Watanabe N.
    Nature Astronomy, 2, 228-232 (2018) doi:10.1038/s41550-018-0380-9
    Press release "Baby, it’s cold outside: understanding conditions for star formation", Hokkaido University
    
    2017
    
    
37. "Deuterium fractionation upon the formation of hexamethylenetetramines through photochemical reactions of interstellar ice analogs containing deuterated methanol isotopologues"
    Oba Y.,Takano Y., Naraoka H., Kouchi A. and Watanabe N.
    Astrophysical Journal, 849, 122 (9pp) (2017)



38. "Liquid-like behavior of UV-irradiated interstellar ice analog at low temperatures"
    Tachibana S., Kouchi A., Hama T., Oba Y., Piani L., Sugawara I., Endo Y., Hidaka H., Kimura Y., Murata K., Yurimoto H, and Watanabe N.
    Science Advances, 3, eaao2538 (2017)


2016


39. "Negative catalytic effect of water on the reactivity of hydrogen abstraction from the C-H bond of dimethyl ether by deuterium atoms through tunneling at low temperatures"
    Oba Y., Watanabe N., and Kouchi A.
    Chemical Physics Letters, 662, 14-18 (2016)
    *This article is selected as "Editors Choice".
    



40. "Hydrogen-deuterium substitution in solid ethanol by surface reactions at low temperatures"
    Oba Y., Osaka K., Chigai T., Kouchi A., and Watanabe N.
    Monthly Notices of Royal Astronomical Society, 462, 689-695 (2016)



41. "Deuterium fractionation during amino acid formation by photolysis of interstellar ice analogues containing deuterated methanol"
    Oba Y.,Takano Y., Watanabe N., and Kouchi A.
    Astrophysical Journal Letters, 827, L18 (7pp) (2016)


2015


42. "Chiral Glycine Formation on Cold Interstellar Grains by Quantum Tunneling Hydrogen-Deuterium Substitution Reactions"
    Oba Y., Watanabe N., Osamura Y., and Kouchi A.
    Chemical Physics Letters, 634, 53-59 (2015)
    *This article is selected as "Editors Choice".
    *This article is highlighted in "The Conversation"
    *This article is highlighted in "Cosmos Magagine"
    Press release "Formation Route of First Chiral Amino Acid in the Universe Clarified", Hokkaido University


2014


43. "Hydrogen Isotopic Substitution of Solid Methylamine through Atomic Surface Reactions at Low Temperatures: A Potential Contribution to the D/H Ratio of Methylamine in Molecular Clouds"
    Oba Y., Chigai T., Osamura Y., Watanabe N., and Kouchi A.
    Meteoritics & Planetary Science, 49, 117-132 (2014)



44. "Reaction kinetics and isotope effect of water formation by the surface reaction of solid H₂O₂ with H atoms at low temperatures"
    Oba Y., Osaka K., Watanabe N., Chigai T., and Kouchi A.
    Faraday Discussions, 168, 185-204 (2014)


2012


45. "Physicochemical Processes of Hydrogen on Cosmic Dust in Molecular Clouds"
    Naoki WATANABE, Akira KOUCHI, Tetsuya HAMA, Hiroshi HIDAKA, Yasuhiro OBA, Takeshi CHIGAI
    Hyomen Kagaku (in Japanese), 33, 662-668 (2012)



46. "Octanol-water partition coefficients (K_ow) vs. pH for fluorescent dye tracers (fluorescein, eosin Y), and implications for hydrologic tracer tests"
    Oba Y., and Poulson S. R.
    Geochemical Journal, 46, 517-520 (2012)



47. "Water formation through a quantum tunneling surface reaction, OH + H₂, at 10 K"
    Oba Y., Watanabe N., Hama T., Kuwahata K., Hidaka H., and Kouchi A.
    The Astrophysical Journal, 749, 67(12pp) (2012)


2011


48. "Experimental studies of surface reactions among OH radicals that yield H₂O and CO₂ at 40-60 K"
    Oba Y., Watanabe N., Kouchi A., Hama T., and Pirronello V.
    Physical Chemistry Chemical Physics, 13, 15792-15797 (2011)



49. "Experimental studies on the formation of carbon dioxide in interstellar molecular clouds"
    Yasuhiro OBA, Naoki WATANABE, Akira KOUCHI, Tetsuya HAMA, Valerio PIRRONELLO
    Chikyu Kagaku (in Japanese), 45, 213-226 (2011)



50. "Stable isotopic composition of organic compouds in carbonaceous chondrites and their fractionation processes"
    Yasuhiro OBA
    Researches in Organic Geochemistry (in Japanese), 27, 103-115 (2011)


2010


51. "Formation of carbonic acid (H₂CO₃) by surface reactions of non-energetic OH radicals with CO molecules at low temperatures"
    Oba Y., Watanabe N., Kouchi A., Hama T., and Pirronello V.
    The Astrophysical Journal, 722, 1598-1606 (2010)



52. "Vertical carbon isotope change in acetate in a surface sediment from the northwestern Pacific Ocean"
    Kaneko, M., Oba Y., and Naraoka, H
    Researches in Organic Geochemistry, 26, 73-79 (2010)



53. "Direct evidence for ammonium ion formation in ice through ultraviolet-induced acid-base reaction of NH₃ with H₃O⁺"
    Moon E.-S., Kang H., Oba Y., Watanabe N., and Kouchi A.
    The Astrophysical Journal, 713, 906-911 (2010)



54. "Experimental study of CO₂ formation by surface reactions of non-energetic OH radicals with CO molecules"
    Oba Y., Watanabe N., Kouchi A., Hama T., and Pirronello V.
    The Astrophysical Journal, 712, L174-L178 (2010)



55. "Diel behavior of stable isotopes of dissolved oxygen and dissolved inorganic carbon in rivers over a range of trophic conditions, and in a mesocosm experiment"
    S. R. Parker, C. H. Gammons, S. R. Poulson, M. D. DeGrandpre, C. L. Weyer, M. G. Smith, J. N. Babcock, and Oba Y.
    Chemical Geology, 269, 22-32 (2010)


2009


56. "Oxygen isotope fractionation of dissolved oxygen during abiological reduction by aqueous sulfide"
    Oba Y., and Poulson S.R.
    Chemical Geology, 268, 226-232 (2009)



57. "Elemental and isotope behavior of macromolecular organic matter from CM chondrites during hydrous pyrolysis"
    Oba Y., and Naraoka H.
    Meteoritics and Planetary Science, 44, 943-953 (2009)



58. "Formation of compact amorphous H₂O ice by codeposition of hydrogen atoms with oxygen molecules on grain surfaces"
    Oba Y., Miyauchi N., Chigai T., Hidaka H., Watanabe N., and Kouchi A.
    The Astrophysical Journal, 701, 464-470 (2009)



59. "Oxygen isotope fractionation of dissolved oxygen during reduction by ferrous iron"
    Oba Y., and Poulson S.R.
    Geochimica et Cosmochimica Acta, 73, 13-24 (2009)



60. "Formation of water molecule by surface atomic reactions on interstellar grains at low temperatures"
    Yasuhiro OBA，Naoya MIYAUCHI，Takeshi CHIGAI，Hiroshi HIDAKA，Naoki WATANABE，Akira KOUCHI
    Chikyu Kagaku (in Japanese), 43, 117-131 (2009)


2008


61. "Carbon and hydrogen isotopic fractionation of low molecular weight organic compounds during ultraviolet degradation"
    Oba Y., and Naraoka H.
    Organic Geochemistry, 35, 501-509 (2008)



62. "Compound-specific isotope analysis (CSIA) by gas chromatograph/isotope ratio mass spectrometer (GC/IRMS)"
    Yoshito CHIKARAISHI，Yasuhiro OBA
    Researches in Organic Geochemistry (in Japanese), 23/24, 99-122 (2008)


2007


63. "Carbon and hydrogen isotope fractionation of acetic acid during degradation by ultraviolet light"
    Oba Y., and Naraoka H.
    Geochemical Journal, 41, 103-110 (2007)


2006


64. "Site-specific carbon isotope analysis of aromatic carboxylic acids by elemental analysis-pyrolysis-isotope ratio mass spectrometry"
    Oba Y., and Naraoka H.
    Rapid Communications in Mass Spectrometry, 20, 3649-3653 (2006)



65. "Carbon isotopic composition of acetic acid generated by hydrous pyrolysis of macromolecular organic matter from the Murchison meteorite"
    Oba Y., and Naraoka H.
    Meteoritics and Planetary Science, 41, 1175-1181 (2006)


2003


66. "Different behavior of hydrogen isotope exchange in aqueous solutions between two PAH isomers (fluoranthene and pyrene)"
    Oba Y., and Naraoka H.
    Researches in Organic Geochemistry, 18, 29-35 (2003)

Conference Proceedings

1. V. Pirronello, M. Accolla, T. Hama, H. Hidaka, A. Kouchi, G. Manico,
   Y. Oba, and N. Watanabe
   "Laboratory investigations of physico-chemical processes occurring in icy mantles on interstellar dust grains"
   Physics and Chemistry of ice 2010, pp 361-368, Hokkaido University press (2011)



2. Y. Oba, N. Miyauchi, T. Chigai, H. Hidaka, N. Watanabe, and A. Kouchi
   "Formation of H₂O ice through the surface reaction O₂ + H at low temperatures: Reaction kinetics and structure of the ice"
   Physics and Chemistry of ice 2010, pp 369-378, Hokkaido University press (2011)



3. A. Kouchi, N. Watanabe, H. Hidaka, N. Miyauchi, Oba Y., and T. Chigai,
   "Formation of amorphous H₂O ice from the reactions of cold H atoms with solid O₂ at 10K"
   Cosmic Dust-Near & Far, ASP Conference Series 414, 338, (2009)



4. N. Watanabe, A. Kouchi, H. Hidaka, Oba Y., and N. Miyauchi,
   "Nonenergetic reactions between atomic hydrogen and molecules on interstellar grain surfaces"
   XXVI International Conference on Photonic, Electronic and Atomic Collisions,
   Journal of Physics: Conference Series, 194, 012044, (2009)

Invited talks

1. "Chemical Evolution from the Interstellar Medium to the Solar System: Insight from the Analysis of Asteroidal Materials" ISM2023,Sapporo, Japan, 10th November (2023)


2. "Chemical evolution from molecular clouds to star-forming regions, and beyond"
Chemical Processes in Solar-type Star-Forming Regions,Toulouse, France, 8th June (2023)


3. "Detection of nucleobases in extraterrestrial materials using liquid chromatography coupled with ultra high-resolution mass spectrometry"
JPGU 2023 Meeting, Chiba, Japan, 25th May (2023)


4. "Recent advances in analytical techniques for the identification of specific COMs in photochemically-processed interstellar ice analogs"
43rd COSPAR Scientific Assembly, F3.5,Sydney (online), 31st Jan.(2021)


5. "H₂S, why you no solid at 10 K? -Nonthermal desorption from interstellar icy grains"
JPGU 2018 Meeting, Chiba, Japan, 22nd May (2018)


6. "Experimental studies on the surface reaction of hydrogen sulfide with deuterium atoms on amorphous solid water at 10 K"
ACS Spring National Meeting, New Orleans, USA, 21st March (2018)


7. "Formation of chiral glycine by surface reactions of normal glycine with deuterium atoms at 10 K"
Astrophysical Ices in the Lab (AILab),
Madrid, Spain, 7-8th March (2016)


8. "Formation and deuterium fractionation of water by low-temperature surface reactions in molecular clouds"
Center for Astrochemical Studies Seminar, Munich, Germany, 13th October (2015)


9. "Formation of H₂O ice on cold interstellar grains: Reaction kinetics and the structure of ice"
Workshop on Ice and Water Films,Seoul, Korea, 6-8 May (2013)


10. "Co-evolution of water and organics via surface reactions on interstellar grains"
JPGU 2013 Meeting,Chiba, Japan, 22 May (2013)


11. "Structure of H₂O ice formed by surface reactions of oxygen molecules with hydrogen atoms at low temperatures"
12th International Conference on the Physics and Chemistry of Ice, Hokkaido Univ., 5-10 September, (2010)


12. "Formation of compact amorphous water ice by surface atomic reactions at low temperatures"
2010 Western Pacific Geophysics Meeting, Taipei, Taiwan, 22-25 June, (2010)

Award

1. Nishida Prize (2023) "Organic astrochemical evolution in interstellar environment and the solar system"


2. The Geochemistry Research Association Award for Progress in Geochemistry (2017) "Studies on organic molecules in carbonaceous chondrites and on molecules under simulated interstellar conditions using their stable isotope compositions by novel experimental methods"


3. Young investigator award from The Japanese Association of Organic Geochemists (2010) "Stable isotope compositions of organic compounds in carbonaceous chondrites and its isotope fractionation processes"