Bivariate-t distribution for transition matrix elements in Breit-Wigner to Gaussian domains of interacting particle systems
- Physical Research Laboratory, Ahmedabad 380 009 (India)
- Department of Physics, Faculty of Science, M.S. University of Baroda, Vadodara 390 001 (India)
- Department of Physics, Berhampur University, Berhampur 760 007 (India)
Interacting many-particle systems with a mean-field one-body part plus a chaos generating random two-body interaction having strength {lambda} exhibit Poisson to Gaussian orthogonal ensemble and Breit-Wigner (BW) to Gaussian transitions in level fluctuations and strength functions with transition points marked by {lambda}={lambda}{sub c} and {lambda}={lambda}{sub F}, respectively; {lambda}{sub F}>>{lambda}{sub c}. For these systems a theory for the matrix elements of one-body transition operators is available, as valid in the Gaussian domain, with {lambda}>{lambda}{sub F}, in terms of orbital occupation numbers, level densities, and an integral involving a bivariate Gaussian in the initial and final energies. Here we show that, using a bivariate-t distribution, the theory extends below from the Gaussian regime to the BW regime up to {lambda}={lambda}{sub c}. This is well tested in numerical calculations for 6 spinless fermions in 12 single-particle states.
- OSTI ID:
- 20779250
- Journal Information:
- Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Vol. 73, Issue 4; Other Information: DOI: 10.1103/PhysRevE.73.047203; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-651X
- Country of Publication:
- United States
- Language:
- English
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