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Laboratory Simulation of Chemical Reactions in Interstellar Ices

  • K. Hiraoka (a1), T. Sato (a1) and T. Takayama (a1)

Abstract

The reactions of H atoms with solid thin films at 10 K were studied by using thermal desorption mass spectrometry and FT-IR spectroscopy. The N, C, and O atoms trapped in solid matrices were converted efficiently to fully hydrogenated compounds. In the reaction of H atoms with a solid CO film, the formation of formaldehyde and methanol were confirmed. The relatively low yield of the reaction products suggests either the smaller rate constants of the H atom addition reactions to CO and/or the occurrence of the hydrogen abstraction reaction H + HCO → H2 + CO. The reactions of H atoms with thin films of acetone and 2-propanol were also studied. The major products from acetone were found to be methane and alcohols but 2-propanol was not detected as a reaction product. The reaction of H with 2-propanol led to the formation of methane, alcohols, and acetone as major products.

In the reaction of H with C2H2, C2H6 was found to be the major product but C2H4 could not be detected. This is due to the fact that the first-step addition reaction H + C2H2 → C2H3 is the rate-controlling process and the following reactions to form the final product C2H6 proceed much faster than the initial one. This finding is in accord with the observation of comets Hyakutake and Hale-Bopp, i.e., C2H2 and C2H6 but not C2H4 were detected in the coma of these comets. In the reactions of H with C2H2 and C2H4, the C2H6 product yields increased drastically with decrease of temperature from 50 to 10 K. This is most likely due to the increase of the sticking probability of H atoms on the solid films at lower temperature. These findings led us to conclude that the chemical evolution taking place on the dust grains via H-atom tunneling reactions becomes efficient only at cryogenic temperatures, i.e., ~ 10 K.

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References

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Brown, P.D. & Charnley, S.B. 1990, MNRAS, 244, 432
Crovisier, J. 1998, Faraday Discuss, 109, 437
Crovisier, J., Leech, K., Bockelee-Morvan, D., Brooke, T.Y., Hanner, M.S., Altieri, B., Keller, H.U. & Lellouch, E. 1997, Science, 275, 1904
d'Hendecourt, L.B., Allamandola, L.J., & Greenberg, J.M. 1985, A&A, 152, 130
Gerakines, P.A., Schutte, W.A., & Ehrenfreund, P. 1996, A&A, 312, 289
Greenberg, J.M. & Li, A. 1996, A&A, 309, 258
Greenberg, J.M. & Pirronello, V. 1989, Chemistry in Space, NATO ASI Series, Kluwer Academic, Dordrecht
Hasegawa, T.I., Herbst, E., & Leung, C.M. 1992, ApJ, 82, 167
Hiraoka, K., Ohashi, N., Kihara, Y., Yamamoto, K., Sato, T., & Yamashita, A. 1994, Chem. Phys. Lett., 229, 408
Hiraoka, K., Miyagoshi, T., Takayama, T., Yamamoto, T., & Kihara, Y. 1998a, ApJ, 498, 710
Hiraoka, K., Yamamoto, K., Kihara, Y., Takayama, T., & Sato, T. 1999, ApJ, 514, 524
Hiraoka, K., Yamashita, A., Miyagoshi, T., Ohashi, N., Kihara, Y., & Yamamoto, K. 1998b, ApJ, 508, 423
Hiraoka, K., Yamashita, A., Yachi, Y., et al. 1995, ApJ, 443, 363
Hong, S.S. & Greenberg, J.M. 1980, A&A, 309, 194
Ikezoe, Y., Matsuoka, S., Takebe, M., & Viggiano, A. 1987, Gas Phase Ion-Molecule Reaction Rate Constants Through 1986, Maruzen, Tokyo
Kaiser, R.I., Eich, G., Gabrysch, A., & Roessler, K. 1997, ApJ, 484, 487
Kaiser, R.I., Eich, G., Gabrysch, A., & Roessler, K. 1999, A&A, 346, 340.
Kaiser, R.I. & Roessler, K. 1997, ApJ, 475, 144
Kaiser, R.I. & Roessler, K. 1998, ApJ, 503, 959
Knyazev, V.D., Bencsura, A., Stoliarov, S.I., & Slagle, I.R. 1996b, J. Phys. Chem., 100, 11346
Knyazev, V.D. & Slagle, I.R. 1996a, J. Phys. Chem., 100, 16899
Mumma, M.J., DiSanti, M.A., Russo, N.D., Fomenkova, M., Magee-Sauer, K., Kaminski, C.D., & Xie, D.X. 1996, Science, 272, 1310
Pirronello, V., Biham, O., Liu, C., Shen, L., & Vidali, G. 1997b, ApJ, 483, L131
Pirronello, V., Liu, C., Shen, L., & Vidali, G. 1997a, ApJ, 475, L69
Pirronello, V., Liu, C., Roser, J.E., & Vidali, G. 1999, A&A, 344, 681
Tielens, A.G.G.M. & Allamandola, L.J. 1987, Interstellar Processes, eds. Hollenbach, D.J. & Thronson, H.A. (Reidel: Dordrecht)
Tielens, A.G.G.M. & Hagen, , 1982, A&A, 114, 245
Tokunaga, T., Brooke, T.Y., Weaver, H.A., Crovisier, J., & Bockelée-Morvan, D. 1996, IAU Circ., 6378
Villa, J., Corchado, J.C., Gonzalez-Lafont, A., Lluck, J.M., & Truhlar, D.J. 1998a, J. Am. Chem. Soc., 120, 12141
Villa, J., Gonzalez-Lafont, A., Lluck, J.M., & Truhlar, D.J. 1998b, J. Am. Chem. Soc., 120, 5559
Willliams, D.A. & Millar, T.J. 1993, Dust and Chemistry in Astronomy, IOP, Bristol

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