Low energy proton-proton scattering in effective field theory

Low energy proton-proton scattering is studied in pionless effective field theory. Employing the dimensional regularization and MS-bar and power divergence subtraction schemes for loop calculation, we calculate the scattering amplitude in 1S0 channel up to next-to-next-to leading order and fix low-energy constants that appear in the amplitude by effective range parameters. We study regularization scheme and scale dependence in separation of Coulomb interaction from the scattering length and effective range for the S-wave proton-proton scattering.Comment: 23 pages, 6 eps figures, revised considerably, accepted for publication in Phys. Rev.

Retrieving Nuclear Information from Protons Propagating through A Thick Target

The multiple scattering of high-energy particles in a thick target is fromulated in an impact parameter representation. A formalism similar but not identical to that of Moliere is obtained. We show that calculations of particle beam broadening due to multiple Coulomb scattering alone can be given in closed form. The focus of this study is on whether or not the broadening of the Coulomb angular distribution prevents the retrieval of nuclear-interaction information from mesauring the angular distributions of charged partiles scattered from a thick target. For this purpose, we study multiple scatterings with both the nuclear and Coulomb interactions included and we do not make a small-angle expansion. Condition for retrieving nuclear infomration from high-energy protons propagating through a block of material are obtained.Comment: 29 pages, 13 figure

Measurement of one-particle correlations and momentum distributions for trapped 1D gases

van Hove's theory of scattering of probe particles by a macroscopic target is generalized so as to relate the differential cross section for atomic ejection via stimulated Raman transitions to one-particle momentum-time correlations and momentum distributions of 1D trapped gases. This method is well suited to probing the longitudinal momentum distributions of 1D gases in situ, and examples are given for bosonic and fermionic atoms.Comment: 4 pages, 2 .eps figure

Multiphoton ionization of H- and He in intense laser fields

The recently proposed R-matrix-Floquet theory of multiphoton processes has been used to calculate multiphoton ionization rates for the two-electron systems H- and He in intense laser fields. The theory is nonperturbative and includes electron-electron correlations. Results are presented for total and partial multiphoton ionization rates and novel nonperturbative correlation effects are discussed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe