Scattered Halos around H$_2$O Masers
Session 81 -- YSO's, Masers and Molecules
Display presentation, Wednesday, 11, 1995, 9:20am - 6:30pm

## [81.13] Scattered Halos around H$_2$O Masers

C.R.Gwinn (UCSB)

I report detection and observations of scattered halos around astrophysical H$_2$O masers. I argue that Rayleigh scattering in the HII region that encloses the masers is responsible for these halos. Just as fog reveals the shape of a searchlight beam, this scattering reveals the pattern of radiation from the highly-beamed masers. Analysis of the properties of the halos indicates that the beam of radiation from the maser has an opening angle of $0.002<\theta<0.02$ radians.