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Atomic, Molecular and Optical Physics Commons™
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Articles 1 - 3 of 3
Full-Text Articles in Atomic, Molecular and Optical Physics
Creation Of Multiple Electron-Positron Pairs In Arbitrary Fields, T Cheng, Q Su, Rainer Grobe
Creation Of Multiple Electron-Positron Pairs In Arbitrary Fields, T Cheng, Q Su, Rainer Grobe
Faculty publications – Physics
We examine the spontaneous breakdown of the matter vacuum triggered by an external force of arbitrary strength and spatial and temporal variations. We derive a nonperturbative framework that permits the computation of the complete time evolution of various multiple electron-positron pair probabilities. These time-dependent probabilities can be computed from a generating function as well as from solutions to a set of ratelike equations with coupling constants determined by the single-particle solutions to the time-dependent Dirac equation. This approach might be of relevance to the planned experiments to observe for the first time the laser-induced breakdown process of the vacuum.
Limitations Of Decomposition-Based Imaging Of Longitudinal Absorber Configurations, S D. Campbell, S D. Grobe, I L. Goodin, Q Su, Rainer Grobe
Limitations Of Decomposition-Based Imaging Of Longitudinal Absorber Configurations, S D. Campbell, S D. Grobe, I L. Goodin, Q Su, Rainer Grobe
Faculty publications – Physics
We examine theoretically and experimentally an imaging scheme that uses the transverse intensity profile of the scattered light to reconstruct the locations of absorbers embedded in a turbid medium. This method is based on an a priori knowledge of the scattered light patterns associated with a single absorber that is located at various positions inside the medium. We discuss the range of validity of this method, and its sensitivity with regard to noise, and propose an algorithm to improve its accuracy.
Decomposition-Based Recovery Of Absorbers In Turbid Media, S D. Campbell, I L. Goodin, S D. Grobe, Qichang Su, Rainer Grobe
Decomposition-Based Recovery Of Absorbers In Turbid Media, S D. Campbell, I L. Goodin, S D. Grobe, Qichang Su, Rainer Grobe
Faculty publications – Physics
We suggest that the concept of the point-spread function traditionally used to predict the blurred image pattern of various light sources embedded inside turbid media can be generalized under certain conditions to predict also the presence and location of spatially localized absorbing inhomogeneities based on shadow point-spread functions associated with each localized absorber in the medium. The combined image obtained from several absorbers can then be decomposed approximately into the arithmetic sums of these individual shadow point-spread functions with suitable weights that can be obtained from multiple-regression analysis. This technique permits the reconstruction of the location of absorbers.