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*International Meetings

*Publications

    2022
    • "Penetration of Nonenergetic Hydrogen Atoms into Amorphous Solid Water and their Reaction with Embedded Benzene and Naphthalene"
      M. Tsuge, A. Kouchi, N. Watanabe
      Astrophys. J. 933, 138(9pp) (2022)

    • "Diffusion Activation Energy and Desorption Activation Energy for Astrochemically Relevant Species on Water Ice show No Clear Relation"
      K. Furuya, T. Hama, Y. Oba, A. Kouchi, N. Watanabe, Y. Aikawa
      Astrophys. J. Lett. 933, L16 (2022)

    • "Hydrogen abstraction reactions in formic and thioformic acid isomers by hydrogen and deuterium atoms"
      G. Molpeceres, I. Jiménez-Serra, Y. Oba, T. Nguyen, N. Watanabe, J. García de la Concepción, B. Maté, R. Oliveira, J. Kästner
      Astron. Astrophys. 663, A41 (2022)

    • "Modelling 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
      Front. Astron. Space Sci. 9, 890161 (2022)

    • "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)

    • "Quantifying the chemical desorption of H2S and PH3 from amorphous water ice surfaces"
      K. Furuya, Y. Oba, T. Shimonishi
      Astrophys. J. 926, 171(17pp) (2022)

    • "Thermal Desorption of Interstellar Ices: A Review on the Controlling Parameters and Their Implications from Snowlines to Chemical Complexity"
      M. Minissale, Y. Aikawa, E. Bergin, M. Bertin, W. A. Brown, S. Cazaux, S. B. Charnley, A. Coutens, H. M. Cuppen, V. Guzman, H. Linnartz, M. R. S. McCoustra, A.Rimola, J.G.M. Schrauwen, C. Toubin, P. Ugliengo, N. Watanabe, V. Wakelam, F. Dulieu
      ACS Earth Space Chem. 6, 597-630

    • "FAUST III. Misaligned rotations of the envelope, outflow, and disks in the multiple protostellar system of VLA4 1623-2417"
      S. Ohashi et al.
      Astrophysical J. 927, 54 (22pp) (2022)

      2021
      • "Measurements of Ortho-to-para Nuclear Spin Conversion of H2 on Low-temperature Carbonaceous Grain Analogs: Diamond-like Carbon and Graphite"
        M. Tsuge, A. Kouchi, N. Watanabe
        Astrophys. J. 923, 71(8pp), (2021)

      • "UV-Induced Formation of Ice XI Observed Using an Ultra-High Vacuum Cryogenic Transmission Electron Microscope and its Implications for Planetary Science"
        A. Kouchi, Y. Kimura, K. Kitajima, H. Katsuno, H. Hidaka, Y. Oba, M. Tsuge, T. Yamazaki, K. Fujita, T. Hama, Y. Takahashi, S. Nakatsunbo, N. Watanabe
        Frontier in Chemistry 9, 799851, (2021)

      • "Successive H-atom Addition to Solid OCS on Compact Amorphous Solid Water"
        T. Nguyen, Y. Oba, W. M. C. Sameera, A. Kouchi, N. Watanabe
        Astrophys. J. 922, 146(13pp), (2021)

      • "Efficient formation pathway of methyl formate: the role of OH radicals on ice dust"
        A. Ishibashi, H. Hidaka, Y. Oba, A. Kouchi, N. Watanabe
        Astrophys. J. Lett. 921, L13(9pp), (2021)

      • "Experimental and computational studies on the physico-chemical behavior of phosphine induced by reactions with H and D atoms on interstellar ice grains"
        T. Nguyen, Y. Oba, W. M. C. Sameera, A. Kouchi, N. Watanabe
        Astrophys. J. 918, 73(15pp), (2021)

      • "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. Sirono, M. Momose, N. Nakatani, K. Furuya, T. Shimonishi, T. Yamazaki, H. Hidaka, Y. Kimura, K. Murata, K. Fujita, S. Nakatsubo, S. Tachibana, and N. Watanabe
        Astrophys. J. 918, 45, (2021)

      • "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. Sirono, S. Okuzumi, M. Momose, K. Furuya and N. Watanabe
        MNRAS 505, 1530.1542 (2021)

      • "Binding energies and sticking coefficients of H2 on crystalline and amorphous CO ice"
        G. Molpeceres, V. Zaverkin, N. Watanabe, J. Kästner
        Astron. Astrophys, 648, A84, (2021)

      • "FAUST II. Discovery of a secondary outflow in IRAS 15398-3359: Variability in outflow direction during the earliest stage of star formation?"
        Y. Okoda et al.
        Astrophysical Journal,910, 11(13pp) (2021)

      • "Rapid Ortho-to-para Nuclear Spin Conversion of H2 on a Silicate Dust Surface"
        M. Tsuge, T. Namiyoshi, K. Furuya, T. Yamazaki, A. Kouchi, N. Watanabe
        Astrophys. J. 908, 234 (2021)

      • "Behavior of Hydroxyl Radicals on Water Ice at Low Temperatures"
        M. Tsuge, N. Watanabe
        Acc. Chem. Res. 54, 471 (2021)

      • "CH3O Radical Binding on Hexagonal Water Ice and Amorphous Solid Water"
        W. M. C. Sameera, S. Bethmini, S. Andersson, M. Al-Ibadi, H. Hidaka, A. Kouchi, G. Nyman, N. Watanabe
        J. Phys. Chem. A 125, 387 (2021)

      • "Delivery of Electrons by Proton-Hole Transfer in Ice at 10 K: Role of Surface OH Radicals"
        K. Kitajima, Y. Nakai, W. M. C. Sameera, M. Tsuge, A. Miyazaki, H. Hidaka, A. Kouchi, N. Watanabe
        J. Phys. Chem. Lett. 12, 704 (2021)

        2020
        • "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)

        • "Behavior of Hydroxyl Radicals on Water Ice at Low Temperatures"
          M. Tsuge, N. Watanabe
          Acc. Chem. Res. 54, 471 (2021)

        • "Photostimulated desorption of OH radicals from amorphous solid water: Evidence for the interaction of visible light with an OH-ice complex"
          A. Miyazaki, N. Watanabe, W. M. C. Sameera, Y. Nakai, M. Tsuge, T. Hama, H. Hidaka, and A. Kouchi
          Phys. Rev. A 102, 052822, (2020)

        • "UV-ray irradiation never causes amorphization of crystalline CO2: A transmission electron microscopy study"
          Masashi Tsuge, Thanh Nguyen, Yasuhiro Ob, Tetsuya Hama, Akira Kouchi, Naoki Watanabe
          Chem. Phys. Lett. 760, 137999 (2020)

        • "FAUST I. The hot corino at the heart of the prototypical Class I protostar L1551 IRS5"
          E. Bianchi et al.
          Mon. Not. R. Astron. Soc. 498, L87 (2020)

        • "Quantitative Anisotropic Analysis of Molecular Orientation in Amorphous N2O at 6 K by Infrared Multiple-Angle Incidence Resolution Spectrometry"
          T. Hama, A. Ishibashi, A. Kouchi, N. Watanabe, N. Shioya, T. Shimoaka, T. Hasegawa
          J. Phys. Chem. Lett. 11, 7857 (2020)

        • "Diffusive hydrogenation reactions of CO embedded in amorphous solid water at elevated temperatures ~70 K"
          Masashi Tsuge, Hiroshi Hidaka, Akira Kouchi, Naoki Watanabe
          Astrophys. J. 900, 187(7pp) (2020)

        • "In vivo characterization of the structures of films of a fatty acid and an alcohol adsorbed on the skin surface"
          T. Hama, A. Kouchi, N. Watanabe, N. Shioya, T. Shimoaka, T. Hasegawa
          Biophys. Chem. 166, 106459 (2020)

        • "An Experimental Study of Chemical Desorption for Phosphine in Interstellar Ice"
          Thanh Nguyen, Yasuhiro Oba, Takashi Shimonishi, Akira Kouchi, Naoki Watanabe
          Astrophys. J. Lett. 898, L52(6pp),(2020)

        • "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.i Suzuki, H. Naraoka, Y. Takano, S. Tachibana, T. Hama, Y. Oba, Y. Kimura, N. Watanabe, A. Kouchi
          Scientific Reports 10, 7755 (2020)

        • "Direct Measurements of Activation Energies for Surface Diffusion of CO and CO2 on Amorphous Solid Water Using In Situ Transmission Electron Microscopy"
          Akira Kouchi, Kenji Furuya, Tetsuya Hama, Takeshi Chiga, Takashi Kozasa, and Naoki Watanabe
          Astrophys. J. Lett. 891, L22(7pp) (2020)

        • "Experimental Approach to Physicochemical Hydrogen Processes on Cosmic Ice Dust"
          N. Watanabe, M. Tsuge
          J. Phys. Soc. Jpn 89, 051015 (2020)

          2019
          • "Ultraviolet-photon exposure stimulates negative current conductivity in amorphous ice below 50 K"
            N. Watanabe, W. M. C. Sameera, H. Hidaka, A. Miyazaki, A. Kouchi
            Chem. Phys. Lett. 737, 136820 (2019)

          • "Nucleobase synthesis in interstellar ices"
            Y. Oba, Y. Takano, H. Naraoka, N. Watanabe and A. Kouchi
            Nature Communications, 10,4413 (2019)

          • "H2 Ortho.Para Spin Conversion on Inhomogeneous Grain Surfaces"
            Kenji Furuya, Yuri Aikawa, Tetsuya Hama, Naoki Watanabe
            Astrophys. J. 882, 172 (11pp) (2019)

          • "Probing the Molecular Structure and Orientation of the Leaf Surface of Brassica oleracea L. by Polarization Modulation-Infrared Reflection-Absorption Spectroscopy"
            T. Hama, K. Seki, A. Ishibashi, A. Miyazaki, A. Kouchi, N. Watanabe, T. Shimoaka, T. Hasegawa
            Plant Cell Physiol 60, 1567 (2019)

          • "Interactions of Atomic and Molecular Hydrogen with a Diamond-like Carbon Surface: H2 Formation and Desorption"
            Masashi Tsuge, Tetsuya Hama, Yuki Kimura, Akira Kouch, Naoki Watanabe
            Astrophys. J. 878, 23 (10pp) (2019)

          • "Physico-chemical Behavior of Hydrogen Sulfide Induced by Reactions with H and D Atoms on Different Types of Ice Surfaces at Low Temperature"
            Yasuhiro Oba, Takuto Tomaru, Akira Kouchi, and Naoki Watanabe
            Astrophys. J. 874, 124 (8pp) (2019)

            2018
            • "Measurements of the Activation Energies for Atomic Hydrogen Diffusion on Pure Solid C0"
              Y. Kimura, M. Tsuge, V. Pirronello, A. Kouchi, N. Watanabe
              Astrophys. J. Lett. 858, L23 (2018)

            • "The Ortho-to-para Ratio of Water Molecules Desorbed from Ice Made from Para-water Monomers at 11K"
              T. Hama, A. Kouchi, N. Watanabe
              Astrophys. J. Lett. 857, L13 (2018)

            • "An infrared measurement of chemical desorption from interstellar ice analogues"
              Y. Oba, T. Tomaru, T. Lamberts, A. Kouchi, N. Watanabe,
              Nature Astronomy, 2, 228-232 (2018)

              2017
              • "Deuterium Fractionation upon the Formation of Hexamethylenetetramines through Photochemical Reactions of Interstellar Ice Analogs Containing Deuterated Methanol Isotopologues"
                Y. Oba, Y. Takano, H. Naraoka, A. Kouchi, N. Watanabe,
                Astrophys. J. Lett. 849, 122 (2017)

              • "H2 formation on interstellar dust grains: The viewpoints of theory, experiments, models and observations"
                V. Wakelam, E. Bron, S. Cazaux, F. Dulieu, C. Gry, P. Guillard, E. Habart, L. Hornekær, S. Morisset, G. Nyman, V. Pirronello, S. D. Price, V. Valdivia, G. Vidali, N. Watanabe
                Molecular Astrophysics 9, 1, (2017)

              • "Laboratory Studies of Methane and Its Relationship to Prebiotic Chemistry"
                K. Kobayashi, W. D. Geppert, N. Carrasco, N. G. Holm, O. Mousis, M. E. Palumbo, J. H. Waite, N. Watanabe, L. M. Ziurys
                Astrobiology 17, 786, (2017)

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

              • "Fast crystalline ice formation at extremely low temperature through water/neon matrix sublimation"
                T. Hama, S. Ishizuka, T. Yamazaki, Y. Kimura, A. Kouchi, N. Watanabe, T. Sugimoto, V. Pirronello,
                Phys. Chem. Chem. Phys. 19, 17677 (2017)

              • "Comprehensive Study of Thermal Desorption of Grain surface Species by Accretion Shocks around Protostars"
                Hitoshi Miura, Tetsuo Yamamoto, Hideko Nomura, Taishi Nakamoto, Kyoko K. Tanaka, Hidekazu Tanaka, Makiko Nagasawa
                Astrophys. J. 839, 47(16pp) (2017)

              • "Hydrogenation and Deuteration of C2H2 and C2H4 on Cold Grains: A Clue to the Formation Mechanism of C2H6 with Astronomical Interest"
                Hitomi Kobayashi, Hiroshi Hidaka, Thanja Lamberts, Tetsuya Hama, Hideyo Kawakita, Johannes Kæstner, Naoki Watanabe
                Astrophys. J. 837, 155 (2017)

              • "Two types of amorphous protein particles facilitate crystal nucleation"
                Tomoya Yamazaki, Yuki Kimura, Peter G. Vekilov, Erika Furukawa, Manabu Shiraie, Hiroaki Matsumoto, Alexander E. S. Van Driessche, Katsuo Tsukamoto
                PNAS 114, 2154-2159 (2017)

              • "Simulations and Spectra of Water in CO Matrices"
                R. Escribano, E. Artacho, A. Kouchi, T. Hama, Y. Kimura, H. Hidaka, and N Watanabe
                Physical Chemistry Chemical Physics 19, 7280-7287 (2017)

              • "Evolution of morphological and physical properties of laboratory interstellar organic residues with ultraviolet irradiation"
                L. Piani, S. Tachibana, T. Hama, H. Tanaka, Y. Endo, I. Sugawara, L. Dessimoulie, Y. Kimura, A. Miyake, J. Matsuno, A. Tsuchiyama, K. Fujita, S. Nakatsubo, H. Fukushi, S. Mori, T. Chigai, H. Yurimoto and A. Kouchi
                The Astrophysical Journal 837, 35 (2017)

              • "Reactive Uptake of Gaseous Sesquiterpenes on Aqueous Surfaces"
                K. Matsuoka, Y. Sakamoto, T. Hama, Y. Kajii, S. Enami
                J. Phys. Chem. A 121, 810-818 (2017)

                2016
                • Selected as the Editors Choice "Matrix sublimation method for the formation of high-density amorphous ice"
                  A. Kouchi, T. Hama, Y. Kimura, H. Hidaka, R. Escribano, N. Watanabe
                  Chemical Physics Letters 658, 287-292 (2016)

                • "Deuterium Fractionation during Amino Acid Formation by Photolysis of Interstellar Ice Analogs Containing Deuterated Methanol"
                  Y. Oba, Y. Takano, N. Watanabe, A. Kouchi
                  Astrophys. J. Lett. 827, L18 (2016)

                • Selected as the Editors Choice "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"
                  Y. Oba, N. Watanabe, A. Kouchi
                  Chem. Phys. Lett. 662, 14 (2016)

                • "Hydrogen.deuterium substitution in solid ethanol by surface reactions at low temperatures"
                  Y. Oba, K. Osaka, T. Chigai, A. Kouchi, N. Watanabe
                  Mon. Not. Roy. Astron. Soc. 462, 689 (2016)

                • Selected as the Editors' Suggestion in PRL "Surface Temperature Dependence of Hydrogen Ortho-Para Conversion on Amorphous Solid Water"
                  H. Ueta, N. Watanabe, T. Hama, A. Kouchi
                  Physical Review Letters 116, 253201 (2016)

                • "Stepwise formation of H3O+(H2O)n in an ion drift tube: Empirical effective temperature of association/dissociation reaction equilibrium in an electric field"
                  Y, Nakai, H. Hidaka, N. Watanabe, T. M. Kojima
                  J. Chem. Phys. 144, 224306 (2016)

                • "Statistical ortho-to-para ratio ofwater desorbed from ice at 10 kelvin"
                  T. Hama, A. Kouchi, and N. Watanabe
                  Science 351, 65 (2016)
                  2015
                  • "Signaturte of Quantum-Tunneling Diffusion of Hydrogen Atoms on Water Ice at 10 K"
                    K. Kuwahata, T. Hama, A. Kouchi, and N. Watanabe
                    Phys. Rev. Lett. 115, 133201 (2015)

                  • Editors Choice! "Chiral glycine formation on cold interstellar grains by quantumtunneling hydrogen.deuterium substitution reactions"
                    Y. Oba, N. Watanabe, Y. Osamura, and A. Kouchi
                    Chem. Phys. Lett. 634, 53-59 (2015)

                  • "Quantum Tunneling Observed without its Characteristic Large Kinetic Isotope Effects"
                    T. Hama, H. Ueta, A. Kouchi, and N. Watanabe
                    PNAS 112, 7438-7443 (2015)

                    2014
                    • "Quantum Tunneling Hydrogenation of Solid Benzene and Its Control via Surface Structure"
                      T. Hama, H. Ueta, A. Kouchi, N. Watanabe, and H. Tachikawa
                      The Journal of Physical Chemistry Letters 5, 3843-3848 (2014)

                    • "Reaction kinetics and isotope effect of water formation by the surface reaction of solid H2O2 with H atoms at low temperatures"
                      Yasuhiro Oba, Kazuya Osaka, Naoki Watanabe, Takeshi Chigai and Akira Kouchi
                      Faraday Discussion 168, 185-204 (2014)
                    2013
                    • "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",
                      Yasuhiro OBA,Takeshi CHIGAI, Yoshihiro OSAMURA, Naoki WATANABE, Akira KOUCH
                      Meteoritics & Planetary Science 1-16 (2013):DOI: 10.1111/maps.12096

                    • "Surface Processes on Interstellar Amorphous Solid Water: Adsorption, Diffusion, Tunneling Reactions, and Nuclear-Spin Conversion"
                      Tetsuya Hama, Naoki Watanabe
                      Chem. Rev. 113, 8783 (2013)
                    2012
                    • ”The Mechanism of Surface Diffusion of H and D Atoms on Amorphous Solid Water: Existence of Various Potential Sites”,
                      T. Hama, K. Kuwahata, N. Watanabe, A. Kouchi, Y. Kimura. T. Chigai, V. Pirronello
                      Astrophys. J. 757, 185 (2012)

                    • “Water Formation Through a Quantum Tunneling Surface Reaction, OH + H2, at 10 K", Y. Oba, N. Watanabe, T. Hama, K. Kuwahata, H. Hidaka, A. Kouchi,
                      Astrophys. J. 749:67 (2012)

                    2011
                    • “Spin temperature of water molecules desorbed from the surfaces of amorphous solid water, vapor-deposited and produced from photolysis of a CH4/O2 solid mixture"
                      T. Hama, N. Watanabe, A. Kouchi, and M. Yokoyama.
                      Astrophys. J. Lett. 738, L15 (2011)

                    • “FTIR study of ammonia formation via the successive hydrogenation of N atoms trapped in a solid N2 matrix at low temperatures"
                      H. Hidaka, M. Watanabe, A. Kouchi and N. Watanabe.
                      Phys. Chem. Chem.l Phys. 13,15798 (2011)

                    • “Experimental studies of surface reactions among OH radicals that yield H2O and CO2 at 40-60 K"
                      Y. Oba, N. Watanabe, A. Kouchi, T. Hama, and V. Pirronello.
                      Phys. Chem. Chem. Phys. 13, 15792 (2011)

                    • “A theoretical and experimental study on translational and internal energies of H2O and OH from the 157 nm irradiation of amorphous solid water at 90 K"
                      S. Andersson, C. Arasa, A. Yabushita, M. Yokoyama, T. Hama, M. Kawasaki, C. M. Western and M. N. R. Ashfold.
                      Phys. Chem. Chem. Phys. 13, 15810 (2011)

                    • “Surface abundance change in vacuum ultraviolet photodissociation of CO2 and H2O mixture ices"
                      T. Kinugawa, A. Yabushita, M. Kawasaki, T. Hama, and N. Watanabe.
                      Phys. Chem. Chem. Phys. 13, 15785 (2011)

                    • “Laboratory studies on the formation of formic Acid (HCOOH) in interstellar and cometary ices"
                      C. J. Bennett, T. Hama, Y. S. Kim, M. Kawasaki, and R. I. Kaiser,
                      Astrophys. J. 727, 27 (2011)

                    • “Translational and rotational energy measurements of desorbed water molecules in their vibrational ground state following 157 nm irradiation of amorphous solid water”
                      T. Hama, M. Yokoyama, A. Yabushita, M. Kawasaki, & N. Watanabe,
                      Nucl. Instr. Methods B 269, 1011-1015 (2011)

                    2010
                    • “Formation of Carbonic Acid (H2CO3) by Surface Reactions of Non-energetic OH Radicals with CO Molecules at Low Temperatures”
                      Y. Oba, N. Watanabe, A. Kouchi, T. Hama, & V. Pirronello,
                      Astrophys. J. 722, 1598-1606. (2010)

                    • “Role of OH radicals in the formation of oxygen molecules following vacuum ultraviolet photodissociation of amorphous solid water”
                      T. Hama, M. Yokoyama, A. Yabushita, & M. Kawasaki,
                      J. Chem. Phys. 133, 104504 (2010)

                    • “Direct measurements of hydrogen atom diffusion and the spin temperature of nascent H2 molecule on amorphous solid water”
                      N. Watanabe, Y. Kimura, A. Kouchi, T. Chigai, T. Hama, & V. Pirronello,
                      Astrophys. J. Lett. 714, L233 (2010)

                    • “A desorption mechanism of water following vacuum-ultraviolet irradiation on amorphous solid water at 90 K”
                      T. Hama, M. Yokoyama, A. Yabushita, M. Kawasaki, S. Andersson, C.M. Western, M.N.R. Ashfold, R.N. Dixon, & N. Watanabe,
                      J. Chem. Phys. 132, 164508 (2010)

                    • “Direct evidence for ammonium ion formation in ice through ultraviolet-induced acid-base reaction of NH3 with H3O+
                      E-S. Moon, H. Kang, Y. Oba, N. Watanabe, & A. Kouchi,
                      Astrophys. J. 713, 906 (2010)

                    • “Experimental study of CO2 formation by surface reactions of non-energetic OH radicals with CO molecules”
                      Y. Oba, N. Watanabe, A. Kouchi, T. Hama, & V. Pirronello,
                      Astrophys. J. Lett. 712, L174 (2010)