Experiment planning
From GOSIA
(Created page with "The GOSIA suite of codes are ideally suited to the design and planning of heavy-ion induced Coulomb excitation experiments as well as the subsequent analysis. Coulomb excitation ...") |
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scattering cross sections at large scattering angles in a manner that mimics | scattering cross sections at large scattering angles in a manner that mimics | ||
the reorientation effect corresponding to a negative static quadrupole moment. | the reorientation effect corresponding to a negative static quadrupole moment. | ||
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| + | Chapter 2 of the Gosia manual discusses the issue of safe bombarding energy in detail. | ||
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| + | ==The semiclassical approximation== | ||
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| + | The long range of the Coulomb interaction, coupled with the small integrationstep size necessitated by the short wavelength, and the large number of | ||
| + | partial waves that make significant contributions, conspire to make it | ||
| + | impractical to use fully quantal codes with current computers that are capable | ||
| + | of handling the large number of coupled channels important to heavy-ion | ||
| + | induced Coulomb excitation. Fortunately a considerable simplification | ||
| + | can be achieved by assuming a semiclassical treatment of two-body | ||
| + | kinematics as pioneered by Alder and Winther.<ref>K. Alder, A. Winther, K. Dan. Vidensk et al., Mat. Fys. Medd. 32, Number 8 (1960).</ref> | ||
| + | The semiclassical picture exploits the fact that the monopole-monopole Coulombinteraction <math>Z_1 Z_2 e^2/r</math> | ||
| + | dominates and determines the relative motion of the two colliding nuclei. | ||
| + | The semiclassical picture assumes that the size of the | ||
| + | incoming projectile wavepacket is small compared to the | ||
| + | dimensions of the classical hyperbolic trajectory which is | ||
| + | expressed in terms of the [[Sommerfeld_parameter | Sommerfeld parameter]]. | ||
==Notes== | ==Notes== | ||
<references/> | <references/> | ||
