Water in the interstellar media of galaxies

Floris F. S. van Der Tak*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

1 Citation (Scopus)
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This paper reviews recent observations of water in Galactic interstellar clouds and nearby galactic nuclei. Two results are highlighted: (1) Multi-line H2O mapping of the Orion Bar shows that the water chemistry in PDRs is driven by photodissociation and -desorption, unlike in star-forming regions. (2) High-resolution spectra of H2O and its ions toward 5 starburst / AGN systems reveal low ionization rates, unlike as found from higher-excitation lines. We conclude that the chemistry of water strongly depends on radiation environment, and that the ionization rates of interstellar clouds decrease by at least 10 between galactic nuclei and disks.

Original languageEnglish
Pages (from-to)395-399
Number of pages5
JournalProceedings of the International Astronomical Union
Issue numberA29B
Publication statusPublished - Aug-2015


  • astrochemistry
  • galaxies: ISM
  • ISM: molecules

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