Accession Number : ADA018458

Title :   The Unusual H2O Maser Source Near Herbig-Haro Object Number 11,


Personal Author(s) : Lo,K. Y. ; Morris,M. ; Moran,J. M. ; Haschick,A. D.

Report Date : 1975

Pagination or Media Count : 18

Abstract : H2O emission spectra of an unusual source near Herbig-Haro (HH) 11 have been monitored over a 14-month period. Variations of the intensity and the radial velocity of the emission are noticeable on time scales as short as one day. At any given time, only one or two velocity components are present in the spectrum. The variations are such that each component appears and disappears at a fixed radial velocity, and new components appear at seemingly random velocities within a 40 km/s range. It is suggested that the exciting source is losing mass via a stellar wind, and that the H2O emission arises in the transition region between the cavity created by the stellar wind and the surrounding molecular medium. The proposed model can be tested by VLBI observations; an accurate position for the H2O maser source is required to determine the physical relationship between the maser source and the IR or HH objects. (Author)

Descriptors :   *Radio sources(Astronomy), *Interstellar matter, Nebulae, Masers, Emission spectra, Infrared radiation, Water vapor, Spatial distribution, Stellar atmospheres, Line spectra

Subject Categories : Astrophysics

Distribution Statement : APPROVED FOR PUBLIC RELEASE