Positron–hydrogen scattering with quadratic variational methods

1982 ◽  
Vol 60 (4) ◽  
pp. 577-580 ◽  
Author(s):  
M. A. Abdel-Raouf
Keyword(s):  
Elastic Scattering ◽  
Variational Methods ◽  
Phase Shifts ◽  
S Wave ◽  
Variational Techniques ◽  
Wave Phase

New variational techniques in which the functional [Formula: see text] is minimized are used to calculate the S-wave phase shifts of e+–H elastic scattering. The convergence of these phases, as n increases, is precisely investigated.

KN s-wave phase shifts in the non-relativistic quark model

1995 ◽  
Vol 589 (4) ◽  
pp. 585-600 ◽  
Author(s):  
B. Silvestre-Brac ◽  
J. Leandri ◽  
J. Labarsouque
Keyword(s):  
Quark Model ◽  
Phase Shifts ◽  
Relativistic Quark Model ◽  
S Wave ◽  
Wave Phase

FERMI PAIRING IN DILUTE 3He-HeII MIXTURES

2006 ◽  
Vol 20 (18) ◽  
pp. 2491-2504 ◽  
Author(s):  
M. K. AL-SUGHEIR ◽  
H. B. GHASSIB ◽  
B. R. JOUDEH
Keyword(s):  
Phase Shift ◽  
Crucial Role ◽  
Relative Phase ◽  
Phase Shifts ◽  
Fermi Momentum ◽  
Relative Momentum ◽  
Many Body ◽  
S Wave ◽  
Wave Phase ◽  
Zero Values

In this paper the Galitskii–Migdal–Feynman (GMF) formalism is applied to dilute 3He-HeII mixtures. In particular, the effect of the hole-hole scattering on pairing in these systems is investigated. To this end, the relative phase shifts incorporating many-body effects based on both Brueckner–Bethe–Goldstone (BBG) and GMF formalisms are calculated. In the GMF formalism, the S-wave phase shift at zero relative momentum is –π and has a cusp at the Fermi momentum; while in the BBG formalism, this phase shift has zero values up to the Fermi momentum. From these results we conclude that hole-hole scattering plays a crucial role in any possible fermion-fermion pairing in these systems.

Positron–Helium Scattering Cross Sections and Phase Shifts below 19 eV

1973 ◽  
Vol 51 (14) ◽  
pp. 1565-1572 ◽  
Author(s):  
B. Jaduszliwer ◽  
D. A. L. Paul
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Phase Shifts ◽  
S Wave ◽  
Wave Phase ◽  
Entire Energy Range ◽  
Nice Agreement ◽  
Scattering Cross Sections ◽  
D Wave

The total cross sections for elastic scattering of positrons in the energy range from 4 to 19 eV have been measured by the method of transmission. By varying a magnetic field applied along the axis of the scattering chamber the transmitted fraction of the beam is altered, from which individual phase shifts can be extracted. s-, p-, and d-wave phase shifts are given over the entire energy range. The s-wave phase shifts are in agreement with values published by Drachman in 1968, while the p- and d-wave phase shifts are intermediate between values calculated by the same author in 1966 and 1971. The experimental results agree with those of Costello et al., and marginally with our own 1972 results, but are significantly different from those of Canter et al. We compute that the Ramsauer minimum in the diffusion cross section must be 0.04πa02 at 1.6 eV while the minimum in the total cross section is 0.11πa02 at 2.1 eV. The shoulder breadth observed in annihilation experiments is in nice agreement with what one would predict from our phase shifts.

scholarly journals Scattering Cross Sections in Argon from Electron Transport Parameters

1982 ◽  
Vol 35 (1) ◽  
pp. 35 ◽  
Author(s):  
GN Haddad ◽  
TF O'Malley
Keyword(s):  
Phase Shift ◽  
Cross Section ◽  
Cross Sections ◽  
Lateral Diffusion ◽  
Phase Shifts ◽  
P Wave ◽  
Transport Parameters ◽  
S Wave ◽  
Wave Phase ◽  
Range Theory

Previously determined experimental drift velocities Vdr and ratios of lateral diffusion coefficient to mobility DT/µ have been refitted directly with a three parameter modified effective range theory (MER T) representation of the S wave phase shift, a one parameter fit to the P wave phase shift and fixed higher partial wave phase shifts. The MERT representation now extends to 1·0 eV, a threefold extension of the energy range of the MERT fit reported by Milloy et al. (1977). The total cross section derived from the phase shifts is also reported, together with the differential cross section at 1·0 eV which is compared with a previous experimental determination.

Sign in / Sign up

Export Citation Format

Share Document