Cosmic rays may provide the energy flux necessary for the continual synthesis of molecules in dense clouds, according to this detailed model of the carbon, oxygen, hydrogen and nitrogen chemistry of those regions.
The expanding universe is old and has a radius of light years or Matter in the universe, distributed in a highly non‐uniform manner, is concentrated largely in galaxies, which occupy only a minute fraction of the volume of the universe. In addition to stars, most galaxies contain diffuse, low density interstellar matter. Because interstellar matter is most easily studied in our own galaxy, the discussion here will focus on it, although this discussion should be pertinent to other galaxies as well.
References
1. An excellent survey of the interstellar medium is given in L. Spitzer, Jr, “Diffuse Matter in Space,” Interscience, New York (1968).
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4. P. M. Solomon, PHYSICS TODAY, March 1973, page 32.
5. For HCO+ see: L. E. Snyder, D. Buhl, Nature 227, 862 (1970); https://doi.org/NATUAS L. E. Snyder, J. M. Hollis, B. L. Ulich, F. J. Lovas, D. Buhl, Bull. Am. Astron. Soc. 7, 497 (1975). https://doi.org/AASBAR For HCO+ see: W. Klemperer, Nature 227, 1230 (1970); https://doi.org/NATUAS U. Wahlgren, B. Liu, P. K. Pearson, H. F. SchaeferIII, Nature Phys. Sci. 246, 4 (1973). https://doi.org/NPSCA6 For N2H+ see: P. Thaddeus, B. E. Turner, Astrophys. J. (Lett.) 201, L25 (1975); https://doi.org/AJLEAU S. Green, J. A. MontgomeryJr, P. Thaddeus, Astrophys. J. (Lett.) 193, L89 (1974).https://doi.org/AJLEAU
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More about the Authors
Eric Herbst.
Department of Chemistry, College of William and Mary, Williamsburg, Virginia.
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