3,742 research outputs found
VLA observations of 6-cm excited OH
The VLA was used to determine precise positions for 4765-MHz OH maser
emission sources toward star-forming regions which had been observed about
seven months earlier with the Effelsberg 100-meter telescope. The observations
were successful for K3-50, DR21EX, W75N, and W49A. No line was detected toward
S255: this line had decreased to less than 5 per cent of the flux density
observed only seven months earlier. The time-variability of the observed
features during the past 30 years is summarised. In addition, to compare with
the Effelsberg observations, the 4750-MHz and 4660-MHz lines were observed in
W49A. These lines were found to originate primarily from an extended region
which is distinguished as an exceptional collection of compact continuum
components as well as by being the dynamical centre of the very powerful H_2 O
outflow.Comment: 11 pages, will require MN style file to process. MNRAS, accepted Oct
15, 200
Law of the Sea - Shipping - State Regulation of Bays - Rhode Island\u27s Statute Regulating Pilotage of Block Island Sound is Within 46 U.S.C. §211 (1970) Warner v. Dunlap
FACTORS INFLUENCING CONSUMER DECISIONS RELATED TO "NATURAL" BEEF IN THE SOUTHERN PLAINS
Consumer/Household Economics,
Ultrasonic testing : an aid to better breeding
THE ultrasonic tester was originally developed as a metal flaw-detector for industrial purposes, and its usefulness for making carcass measurements on the live pig was first demonstrated about 10 years ago
Profitable bacon production in a small herd
PIG HERDS are tending to become larger and more specialised, but it is still possible for the small herd of less than 20 sows to absorb by-products and spare labour very profitably.
These advantages can be lost if the scale is larger
Breeding better pigs
IN the past, pig breeders have tended to select animals on physical characteristics, many of which have little or no relevance to economy of production.
Selection techniques now available open up the possibility of improved pig production efficiency
Photoassociation dynamics in a Bose-Einstein condensate
A dynamical many body theory of single color photoassociation in a
Bose-Einstein condensate is presented. The theory describes the time evolution
of a condensed atomic ensemble under the influence of an arbitrarily varying
near resonant laser pulse, which strongly modifies the binary scattering
properties. In particular, when considering situations with rapid variations
and high light intensities the approach described in this article leads, in a
consistent way, beyond standard mean field techniques. This allows to address
the question of limits to the photoassociation rate due to many body effects
which has caused extensive discussions in the recent past. Both, the possible
loss rate of condensate atoms and the amount of stable ground state molecules
achievable within a certain time are found to be stronger limited than
according to mean field theory. By systematically treating the dynamics of the
connected Green's function for pair correlations the resonantly driven
population of the excited molecular state as well as scattering into the
continuum of non-condensed atomic states are taken into account. A detailed
analysis of the low energy stationary scattering properties of two atoms
modified by the near resonant photoassociation laser, in particular of the
dressed state spectrum of the relative motion prepares for the analysis of the
many body dynamics. The consequences of the finite lifetime of the resonantly
coupled bound state are discussed in the two body as well as in the many body
context. Extending the two body description to scattering in a tight trap
reveals the modifications to the near resonant adiabatic dressed levels caused
by the decay of the excited molecular state.Comment: 27 pages revtex, 16 figure
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