Spin manipulating stored1.85 GeV/cvector and tensor polarized spin-1 bosons

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

doi:10.1103/physrevstab.8.061001

Abstract

We recently studied the spin manipulation of $1.85\text{ }\text{ }\mathrm{GeV}/c$ vertically polarized deuterons stored in the COSY cooler synchrotron. We adiabatically swept an rf dipole's frequency through an rf-induced spin resonance and observed its effect on the deuterons' vector and tensor polarizations. After optimizing the resonance crossing rate and maximizing the rf dipole's voltage, we measured spin-flip efficiencies of $97\ifmmode\pm\else\textpm\fi{}1%$ and $98.5\ifmmode\pm\else\textpm\fi{}0.3%$ in two separate runs. We also confirmed at higher energy the striking behavior of the spin-1 tensor polarization recently found at IUCF.

Highlights

Many polarized beam experiments are operating in storage rings such as the MIT-Bates storage ring [1], COSY [2], RHIC at Brookhaven [3] and HERA at DESY [4,5]
The apparatus used for this experiment, including the COSY storage ring [21,22,23,24], the EDDA detector [25], the low energy polarimeter, the injector cyclotron, and the polarized ion source [26 –28] are indicated in Fig. 1, along with the rf dipole
We experimentally demonstrated that a single spin-flip efficiency and a single resonance strength can describe both the vector and tensor polarizations

Summary

INTRODUCTION

Many polarized beam experiments are operating in storage rings such as the MIT-Bates storage ring [1], COSY [2], RHIC at Brookhaven [3] and HERA at DESY [4,5]. At a resonant frequency the perturbations can add coherently to induce an rf spin resonance, which can flip the spin of stored polarized particles [7,8,9,10,11,12,13,14,18], such as deuterons [15]. Ramping the rf magnet’s frequency through fr can rotate the deuterons’ polarization direction by an angle around a horizontal axis. Under this rotation, the spin-1 vector and tensor polarizations, PV and PT (sometimes called Pz and Pzz [15]), respectively, transform as PV PiV cos; PT PiT. WRhere e is the deuteron’s charge, p is its momentum, and Brmsdl is the rf dipole’s rms magnetic field integral

APPARATUS

POLARIMETER CALIBRATION

SPIN MANIPULATION

MULTIPLE SPIN FLIPPING

Findings

SUMMARY