H2O megamaser variability

  • Aubrey D. Haschick
  • Willem A. Baan
4. Extragalactic Masers
Part of the Lecture Notes in Physics book series (LNP, volume 412)


A long term monitoring program of extragalactic water vapor sources has been con ducted at Haystack Observatory. The sources monitored are NGC 1068, NGC 3079, NGC 4258, IC 10, and M 33. Variability of line strength, line width, and line velocity of individual line features has been found for all sources. The variability data of extragalactic H2O megamasers is consistent with models of exponential amplification and shock-induced pumping of the molecules.


Line Width Line Strength Center Velocity Line Velocity Extragalactic Source 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Aubrey D. Haschick
    • 1
  • Willem A. Baan
    • 2
  1. 1.Haystack ObservatoryUSA
  2. 2.Arecibo ObservatoryUSA

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