Letter | Published:

A new thermometer for external galaxies

Nature volume 296, pages 632633 (15 April 1982) | Download Citation

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Abstract

We introduce a new spectroscopic method at radio frequencies to measure the temperature of giant cloud complexes in external galaxies. We have detected the λ = 1.3 cm J, K = 2, 2 inversion transition of NH3 in the nucleus of the galaxy IC342. This result, taken together with our previous detection of the J, K = 1, 1 transition1 allows us to deduce a kinetic temperature of 50±15 K and an equivalent size scale of at least 25 pc for the molecular gas. The results are consistent with line formation in the nucleus where very active star formation is taking place.

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References

  1. 1.

    & Astr. Astrophys. 74, L7–19 (1979).

  2. 2.

    in Galactic and Extra-Galactic Radio Astronomy (eds Verschuur, G. L. & Kellermann, K. I.) 119–255 (Springer, New York, 1974).

  3. 3.

    , & Topics Curr. Chem. 44, 1–81 (1974).

  4. 4.

    & A. Rev. Astr. Astrophys. 12, 279–313 (1974).

  5. 5.

    & Microwave Spectroscopy (McGraw-Hill, New York, 1955).

  6. 6.

    IAU Symp. No. 84, 413–416 (1979).

  7. 7.

    , & Astr. Astrophys. (submitted).

  8. 8.

    , & Astrophys. J. 246, 761–787 (1981).

  9. 9.

    thesis, Bonn Univ. (1980).

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Author information

Affiliations

  1. Max-Planck-Institut für Radioastronomie, D-5300 Bonn 1, FRG

    • Robert N. Martin
    •  & K. Ruf
  2. Radio Astronomy Laboratory, University of California, Berkeley, California 94720, USA

    • Paul T. P. Ho

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DOI

https://doi.org/10.1038/296632a0

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