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International Seminar on High Energy Spin Physics Sept. 27- Oct. 1 2005, Dubna. Proton Polarimetry at the U-70 Facility Sandibek Nurushev Institute for High Energy Physics, Protvino, Russia. Proton Polarimetry at Protvino U-70 Facility. Items: Definitions of some terminologies:
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International Seminar on High Energy Spin PhysicsSept. 27- Oct. 1 2005, Dubna Proton Polarimetry at the U-70 FacilitySandibek NurushevInstitute for High Energy Physics, Protvino, Russia
Proton Polarimetry at Protvino U-70 Facility Items: • Definitions of some terminologies: • The desirable precisions in the beam polarization • Classification of Polarimeters • The general scheme of the U70 facility • Polarimeters: - At very low energies (10-100 KeV, PIBS) - At low energies (0.1-30 MeV, RFQ Linac Ural-30) - At intermediate energies ( 30 MeV-1.5 GeV, Booster) - At higher energies (1.5-70 GeV, U70) - At the extracted beam line (70 GeV) - At the experiment (70 GeV, local polarimeter) • Conclusions Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Polarimetry presents a part of the polarization technology completely devoted to the research and development of the tools for measuring the polarization (vector, tensor, etc.) of targets and beams. Left-right or raw asymmetry Analyzing power is a raw asymmetry normalized to the polarization Factor of Merit M=I·P2 Polarimeter is a tool, designed on the base of the process with the known analyzing power, for the measurement of the beam (target) polarization. Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Polarizer is a process producing the polarized particles. Example: 3He(d,p)4He Analyzer is a process identifying the polarization of the incident particles. • The desirable precisions in the beam polarization measurements: • Single spin asymmetry D(P)=[(ANd)2·L·]-1, Where d stands for the dilution factor,L presents the integrated luminosity, is the useful cross section. • Double-spin asymmetry: D(P)=[(ALLd)2·L·]-1/2. Precision in PB is defined by the following factors: a) PIBS, b) statistics and c) systematics. Classification of polarimeters: a)absolute, b) relative, c) of the general use or local, d) constructive or distrucrive, e) fast or slow and f) contimuos or periodic. Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility 8 7 • Fig.1 presents the following accelerator elements : • Ion Source • Polarized Ion Beam Source (PIBS) • RFQ Linac Ural-30 • Booster U-1.5 • Beam transport from U1.5 to U-70 • U-70 accelerator • Beam extraction and transport line • General and Local polarimeters 2 1 P.I.B.S. I.B.S. U-70 U70 6 URAL30 3 4 U-1.5 U1.5 Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility P I BS Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility PIBS parameters: Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Linac Ural - 30 Proton Polarimetry at Protvino U-70 Facility Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Polarimeter for Linac: p↑+ = p + (W.G. Weitkamp and W. Haeberli, Nucl. Phys. 83 (1966) 46-54). Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Booster-1.5 Proton Polarimetry at Protvino U-70 Facility Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Booster-1.5 (cont) Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Polarimeter for Booster U-1.5 Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Synchrotron U70 Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Synchrotron U70 (cont) Operating conditions: Acc. Cycle(sec)=flat (2.2)+ramp(2.8)+flat(2)+down(2.8)-standard. Extr. Plato 2-3-4 s for 70-60-50 GeV correspondingly. Operaion is foreseen for crossing the critical energy. Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Proton Polarimetry at Protvino U-70 Facility Operating conditions: • Acc. Cycle(sec)=flat (2.2)+ramp(2.8)+flat(2)+down(2.8)-standard. Extr. Plato 2-3-4 s for 70-60-50 GeV correspondingly. Operation is foreseen for crossing the critical energy. Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
AGS CNIPolarimeter • Measuring the recoil carbons from • Carbon identification by kinematics cut (banana cut) Ultra thin Carbon ribbon Target (5 cm long, 3.5mg/cm2 ,600mm) beam view Si strip detectors (TOF, EC) 60cm originates from anomalous magnetic moment of p Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Relative polarimeters at U70 GeV Two external polarimeters: A. Using the internal targets: a) p↑+A→+ + X, b) p↑+A→- + X B. Extraction of the small portion of the internal polarized proton beam by bent crystal and measure the asymmetry in inclusive pion productions. Goal: selection of the local polarimeter for the experimental set-up. References: 1. Yu.B. Bushnin et al., Phys. Lett., 29 B (1969) 48. 2. Yu.P. Gorin et al., Sov. J. Nucl. Phys. 14 (1971) 004. 3. N.I. Bojko et al., IHEP Preprint 70-79, Serpukhov, 1970. Assuming AN(-)= AN(+)=0.1, I(pp/s)=1011 one could measure beam polarization with a precision of 5% during 3hrs (-) and 0.5hrs (+) . Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005
Summary • U70 • Two Absolute CNI polarimeters (elastic pp and pC on the internal targets) • One Relative pion inclusive polarimeter (internal targets) • Extraction of the portion of the circulated polarized beam by the bent crystall and polarimetry on this beam • U1.5 • Relative polarimeters on elastic pp or pC - scatterings • Linac Ural-30 • Relative polarimeter based on the elastic p scattering • PIBS • Polarimeter based on the Lamb-shift effect. Sandibek Nurushev, 1 Oct. Dubna, SPIN 2005