Mathematics – Probability
Scientific paper
Oct 1981
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1981apj...249..145d&link_type=abstract
Astrophysical Journal, Part 1, vol. 249, Oct. 1, 1981, p. 145-151.
Mathematics
Probability
43
Cosmic Dust, H Ii Regions, High Temperature Gases, Interstellar Masers, Nebulae, Water Masers, Astronomical Models, Far Infrared Radiation, Interstellar Matter, Radiative Transfer, Water Vapor
Scientific paper
A collisional pump with an internal sink is proposed for the water masers associated with H II regions, where the population inversion occurs due to the absorption by cold ice-mantle grains in a highly dusty cloud of the far-infrared line radiation of hot water vapor. A new escape probability method is developed to calculate the transfer of line radiation in dusty medium. The pump mechanism explains the power of usual maser sources associated with H II regions and the enormous power of the sources associated with W49 N and external galaxies. Models of maser clouds have a radius of 5 x 10 to the 15th-10 to the 16th cm, an H2 number density of 4 x 10 to the 9th/cu cm, an expansion velocity of 10-30 km/s, a kinetic temperature of 350 K, and a grain temperature of 100 K. Giant maser sources require grains of the size about 1 micron. The apparent size of the emission spots (approximately 10 to the 13th cm) observed by VLBI is interpreted as due to a fluctuation in the cloud, and the assembly of the spots is spread within a size of 10 to the 16th cm. The temperature difference between the dust and gas is due to a relaxation process after an infrared burst accompanying protostar formation.
No associations
LandOfFree
Hot-gas cold-dust pumping for water masers associated with H II regions does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Hot-gas cold-dust pumping for water masers associated with H II regions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hot-gas cold-dust pumping for water masers associated with H II regions will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1468530