16 th International Spin Physics Symposium October 10
16 th International Spin Physics Symposium, October 10 -16, 2004, Trieste Energy dependence of helicity-flip amplitudes in the small-angle elastic pp-scattering Sergey Troshin* Institute for High Energy Physics, Protvino * in collaboration with Nikolai Tyurin
Plan: • Sum Rules for Spin Asymmetries • Helicity Amplitudes at Small t
Sum rules rotational invariance Inclusive processes: Elastic and inelastic binary reactions: Unpolarazided scattering (valid for all energies)
Rotational invariance
Sum rules for spin correlation parameters in elastic pp-scattering
Polarization and analyzing power in binary reactions should have sign changing t-dependence (oscillations). Typical pattern of the experimental data for binary processes t At low energies experimentalists can cover a whole t region and the above sum rules are most interesting at such energies.
Sum rules is the testground for the models, e. g. popular assumption that is not valid for the general case of binary reactions
Small t /elastic pp Spin properties of diffraction Single helicity flip amplitude CNI polarimetry unitarity cannot rise at high energies faster than S. T. , N. Tyurin, Phys. Lett. B 459 (1999) 641
Double helicity-flip (DHF) amplitudes and their role Multiple dips when DHF amplitudes are neglected t
Unitarization: rational form of unitarization Potential scattering
Explicit solutions can be obtained for all 5 helicity amplitudes Peripheral b-dependence for HF amplitudes b
i=2, 4, 5 This result of unitarity (rational form of unitarization) allows one to get better upper bounds for HF amplitudes
cannot rise faster than DHF amplitudes are proportional to t at small scattering angles, but they can dominate in the region of moderate momentum transfers S. T. , N. Tyurin, Phys. Rev. D 70, 057503, 2004; Phys. Lett. B 580 (2004) 54.
- Slides: 13