Submillimeter water masers

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/185663· OSTI ID:7135203

Menten, K M; Melnick, G J; Phillips, T G ^[1]

---

1. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA) California Institute of Technology, Pasadena (USA)

The first astronomical detection of the 10(29) - 9(36) transition of water vapor (H2O) at a frequency near 321 GHz is reported. The line was detected toward the star-forming regions W3(OH), W49N, W51 IRS 2, and W51 Main, and the supergiant star VY CMa. In all cases, probably, maser action is observed. Since the 10(29) level of H2O is at an energy of 1861 K above the ground state, the 10(29) - 9(36) line probes very hot molecular material. The 10(29) - 9(36) emission is found at velocities that are near the systemic velocities of the regions studied. The strongest features in spectra of the well-studied 22 GHz 6(16) - 5(23) transition are generally found at similar velocities. The 10(29) - 9(36) spectra do not show counterparts to the high-velocity features observed in the 22 GHz line, but this may be due to the limited sensitivity of the observations. 21 refs.

• OSTI ID: 7135203
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 350; ISSN ASJOA; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AMPLIFIERS
COSMIC GASES
DETECTION
ELECTROMAGNETIC RADIATION
ELECTRONIC EQUIPMENT
ENERGY-LEVEL TRANSITIONS
EQUIPMENT
FLUIDS
GASES
GIANT STARS
HYDROGEN COMPOUNDS
INFRARED RADIATION
INTERSTELLAR SPACE
MASERS
MICROWAVE AMPLIFIERS
MICROWAVE EQUIPMENT
MOLECULES
OXYGEN COMPOUNDS
RADIATIONS
SPACE
STAR EVOLUTION
STARS
SUPERGIANT STARS
VELOCITY
WATER