12,265 research outputs found
The wave equation on the Schwarzschild metric II: Local decay for the spin 2 Regge Wheeler equation
Odd-type spin 2 perturbations of Einstein's equation can be reduced to the
scalar Regge-Wheeler equation. We show that the weighted norms of solutions are
in L^2 of time and space. This result uses commutator methods and applies
uniformly to all relevant spherical harmonics.Comment: AMS-LaTeX, 8 pages with 1 figure. There is an errata to this paper at
gr-qc/060807
Uniform Decay of Local Energy and the Semi-Linear Wave Equation on Schwarzchild Space
We provide a uniform decay estimate of Morawetz type for the local energy of
general solutions to the inhomogeneous wave equation on a Schwarzchild
background. This estimate is both uniform in space and time, so in particular
it implies a uniform bound on the sup norm of solutions which can be given in
terms of certain inverse powers of the radial and advanced/retarded time
coordinate variables. As a model application, we show these estimates give a
very simple proof small amplitude scattering for nonlinear scalar fields with
higher than cubic interactions.Comment: 24 page
Targets for producing high purity I-123
Tellurium powder in improved targets is bombarded with a cyclotron beam to produce Xe-123. Flowing gas streams carry the Xe-123 through one cold trap which removes Xe-123 that subsequently decays to I-123. During this bombardment energy is deposited in the target material causing its temperature to rise. Some of the tellurium vaporizes and subsequently condenses on surfaces that are cooler than the vaporization temperature. Provision is made for the repeated bombardment of this condensed tellurium
- …