The search for an electric dipole moment (EDM) using a polarized, charged-particle beam in a storage ring requires ring conditions that can maintain a longitudinal, and stable, polarization for times up to 1000 s. The EDM signal is a rotation of this polarization into the vertical direction as a consequence of the radial electric fields present in both electric and magnetic storage rings. A study is beginning at the COoler SYnchrotron (COSY) located at the Forschungszentrum-Jülich to examine the effects of emittance and momentum spread on the spin coherence time. As these effects also appear in the properties of an RF-induced spin resonance, this study began by exciting the 1Gg resonance with fixed and variable frequency RF-solenoid scans and a 0:97 GeV/c polarized deuteron beam. Subsequent model analysis of the data recorded for many different beam and solenoid conditions demonstrated through good agreement with the data that most of the observed effects originated in the time shift of deuterons passing through the solenoid, as they underwent synchrotron oscillations inside first harmonic beam bunching. A model, which does not include the ring lattice, is described along with a summary of phenomena observed during the experiment.
Synchrotron Oscillations Effects on Observations of an RF-solenoid Spin Resonance for a Polarized Deuteron Beam at COSY
GUIDOBONI, Greta;LENISA, Paolo
2012
Abstract
The search for an electric dipole moment (EDM) using a polarized, charged-particle beam in a storage ring requires ring conditions that can maintain a longitudinal, and stable, polarization for times up to 1000 s. The EDM signal is a rotation of this polarization into the vertical direction as a consequence of the radial electric fields present in both electric and magnetic storage rings. A study is beginning at the COoler SYnchrotron (COSY) located at the Forschungszentrum-Jülich to examine the effects of emittance and momentum spread on the spin coherence time. As these effects also appear in the properties of an RF-induced spin resonance, this study began by exciting the 1Gg resonance with fixed and variable frequency RF-solenoid scans and a 0:97 GeV/c polarized deuteron beam. Subsequent model analysis of the data recorded for many different beam and solenoid conditions demonstrated through good agreement with the data that most of the observed effects originated in the time shift of deuterons passing through the solenoid, as they underwent synchrotron oscillations inside first harmonic beam bunching. A model, which does not include the ring lattice, is described along with a summary of phenomena observed during the experiment.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
