Experimental test of the new analytic matrix formalism for spin dynamics

V S Morozov,D Prasuhn,V K Wong,F Hinterberger,A Lehrach,A W Chao,R Maier,H Stockhorst,B Lorentz,K Ulbrich,A D Krisch,R S Raymond,R Gebel,M A Leonova,A Schnase,D W Sivers

doi:10.1103/physrevstab.10.041001

V S Morozov, D Prasuhn + Show 14 more

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https://doi.org/10.1103/physrevstab.10.041001

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Abstract

We recently started testing Chao's proposed new matrix formalism for describing the spin dynamics due to a single spin resonance. The Chao formalism is probably the first fundamental improvement of the Froissart-Stora equation in that it allows analytic calculations of the beam polarization's behavior inside a resonance. We tested the Chao formalism using a $1.85\text{ }\text{ }\mathrm{GeV}/c$ polarized deuteron beam stored in COSY, by sweeping an rf dipole's frequency through 200 Hz, while varying the distance from the sweep's end frequency to an rf-induced spin resonance's central frequency. Since the Froissart-Stora equation itself can make no prediction inside a resonance, we compared our experimental data with the predictions of the Chao formalism and those of an empirical two-fluid model based on the Froissart-Stora equation. The data strongly favor the Chao formalism.

Highlights

SchnaseJAEA/J-PARC, Ring RF Group, Shirakata-Shirane 2-4, Tokai-Mura, Ibaraki 319-1195, Japan (Received 8 February 2007; published 18 April 2007)
There has been considerable interest in polarized scattering experiments at storage rings such as the MIT-Bates Storage Ring [1], COSY [2], RHIC at Brookhaven [3], and HERA at DESY [4,5]
A matrix formalism was recently proposed by Chao [7] to treat many experimental conditions that the Froissart-Stora formula cannot treat

Summary

Schnase

JAEA/J-PARC, Ring RF Group, Shirakata-Shirane 2-4, Tokai-Mura, Ibaraki 319-1195, Japan (Received 8 February 2007; published 18 April 2007). We recently started testing Chao’s proposed new matrix formalism for describing the spin dynamics due to a single spin resonance. The Chao formalism is probably the first fundamental improvement of the Froissart-Stora equation in that it allows analytic calculations of the beam polarization’s behavior inside a resonance. We tested the Chao formalism using a 1:85 GeV=c polarized deuteron beam stored in COSY, by sweeping an rf dipole’s frequency through 200 Hz, while varying the distance from the sweep’s end frequency to an rf-induced spin resonance’s central frequency. Since the Froissart-Stora equation itself can make no prediction inside a resonance, we compared our experimental data with the predictions of the Chao formalism and those of an empirical two-fluid model based on the Froissart-Stora equation. The data strongly favor the Chao formalism

INTRODUCTION

CHAO FORMALISM PREDICTION

TWO-FLUID MODEL PREDICTION

APPARATUS

EXPERIMENTAL TESTS

SUMMARY