Search for methane in comet P/Halley

  • S. Drapatz
  • H. P. Larson
  • D. S. Davis
Conference paper

Summary

A search for gaseous neutral CH4 has been conducted in the coma of comet Halley on March 20, 1986 using a Fourier Transform Spectrometer on the NASA Kuiper Airborne Observatory. In the field-of-view (41″ diam. ≙ 24,000 km) the CH4 rotational temperature is equal to the kinetic temperature of the coma molecules due to collisions in most of the region and is frozen in at the outer edge. The spectrum of the v 3 band is due to fluorescence with the R(3) to R(6) lines being most suitable for Earth-based observations. Measured upper (3 σ) limits of ~4 10−19 W cm −2 for several lines lead to a (5σ) upper limit of 4 1028 CH4 molecules per second. This value corresponds to ~4% of the water vapor production rate at the time of observation.

Key words

comets molecules abundances infrared observations 

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References

  1. Baas, F., Geballe, T.R., Walther, D. M.: 1986, Astrophys. J. 311,L 97Google Scholar
  2. Barnes, W.L., Süsskind, R. H., Hunt, R. H., Plyler, E.K.: 1972, J. Chem. Phys. 56, 5160ADSCrossRefGoogle Scholar
  3. Combes, M. et al.: 1986, 20th ESLAB Symp., ESA SP-250, Vol. I, p. 353Google Scholar
  4. Crovisier, J., Encrenaz, T.: 1983, Astron. Astrophys. 126, 170ADSGoogle Scholar
  5. Crovisier, J.: 1986, Proc. Workshop Cometary Radio Astronomy, Green Bank, West Virginia, USAGoogle Scholar
  6. Davis, D. S., Larson, H. P., Williams, M., Michel, G., Connes, P.: 1980, Appl. Optics 19, 4138ADSCrossRefGoogle Scholar
  7. Drapatz, S., Larson, H.P., Davis, D.S.: 1986, 20th ESLAB Symp., ESA SP-250, Vol. I, p. 347Google Scholar
  8. Gray, D. L., Robiette, A. G.: 1979, J. Mol. Spectr. 77, 440ADSCrossRefGoogle Scholar
  9. Fox, K.: 1970, J. Quant. Spectr. Radiat. Transfer 10, 1335ADSCrossRefGoogle Scholar
  10. Herzberg, G.: 1960, Molecular Spectra and Molecular Structure II, D. v. Nostrand Comp., Princeton, NJGoogle Scholar
  11. Hougen, J. T.: 1976, MTP Int. Rev. Science, Phys. Chem. Series II, Vol. 3, Spectroscopy, Ramsay, D.A., ed. Butterworths, LondonGoogle Scholar
  12. Hübner, W.F., Carpenter, C.W.: 1979, Los Alamos Sci. Lab. Rept., LA-8085-MSGoogle Scholar
  13. Hübner, W.F.: 1985, in Molecular Astrophysics, eds. G.H.F. Diercksen, W.F. Hübner, P.W. Langhoff, Reidel, Dordrecht, p. 311Google Scholar
  14. Hübner, W.F.: 1986 (private communication)Google Scholar
  15. Karbach, A., Hess, P.: 1985, J. Chem. Phys. 83, 1075ADSCrossRefGoogle Scholar
  16. Knacke, R., Brooke, T.Y., Joyce, R.R.: 1986, Astrophys. J. 310,L49ADSCrossRefGoogle Scholar
  17. Krankowsky, D. et al.: 1986, Nature 321, 326ADSCrossRefGoogle Scholar
  18. Lambert, J. D.: 1977, Vibrational and Rotational Relaxation in Gases, Clarendon Press, OxfordGoogle Scholar
  19. Larson, H.P., Davis, D.S., Mumma, M.J., Weaver, H.A.: 1986, Astrophys. J. 309, L95ADSCrossRefGoogle Scholar
  20. Roche, A.E., Cosmovici, C.B., Drapatz, S., Michel, K.W., Wells, W.C.: 1975, Icarus 24, 120ADSCrossRefGoogle Scholar
  21. Rosenberg, A., Ozier, I., Kudian, A.K.: 1972, J. Chem. Phys. 57, 568ADSCrossRefGoogle Scholar
  22. Weaver, H. A., Mumma, M.J.: 1984, Astrophys. J. 276, 782ADSCrossRefGoogle Scholar
  23. Weaver, H.A., Mumma, M.J., Larson, H.P., Davis, D.S.: 1986, Nature 324, 441ADSCrossRefGoogle Scholar
  24. Whipple, F.L.: 1950, Astrophys. J. 111, 375ADSCrossRefGoogle Scholar
  25. Yamamoto, T.: 1982, Astron. Astrophys. 109, 326ADSGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • S. Drapatz
    • 1
  • H. P. Larson
    • 2
  • D. S. Davis
    • 2
  1. 1.Max- Planck-Institut für extraterrestrische PhysikGarchingFederal Republic of Germany
  2. 2.The University of ArizonaTucsonUSA

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