Proton Polarimetry at the U-70 Facility Sandibek Nurushev Institute for High Energy Physics, Protvino, Russia International Seminar on High Energy Spin Physics Sept. 27- Oct , Dubna

Sandibek Nurushev, 1 Oct. Dubna, SPIN 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 ( KeV, PIBS) - At low energies ( MeV, RFQ Linac Ural-30) - At intermediate energies ( 30 MeV-1.5 GeV, Booster) - At higher energies ( GeV, U70) - At the extracted beam line (70 GeV) - At the experiment (70 GeV, local polarimeter) Conclusions

Sandibek Nurushev, 1 Oct. Dubna, SPIN 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·P 2 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 Proton Polarimetry at Protvino U-70 Facility Polarizer is a process producing the polarized particles. Example: 3He(d,p) 4 He Analyzer is a process identifying the polarization of the incident particles. The desirable precisions in the beam polarization measurements: 1.Single spin asymmetry D(P)=[(A N d) 2 · L ·  ] -1, Where d stands for the dilution factor, L presents the integrated luminosity,  is the useful cross section. 2.Double-spin asymmetry: D(P)=[(A LL d) 2 · L ·  ] -1 /2. Precision in P B 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 U70 U1.5 U-70 U-1.5 I.B.S. P.I.B.S. URAL30URAL30 Fig.1 presents the following accelerator elements : 1.Ion Source 2.Polarized Ion Beam Source (PIBS) 3.RFQ Linac Ural-30 4.Booster U Beam transport from U1.5 to U-70 6.U-70 accelerator 7.Beam extraction and transport line 8.General and Local polarimeters Proton Polarimetry at Protvino U-70 Facility

Sandibek Nurushev, 1 Oct. Dubna, SPIN Proton Polarimetry at Protvino U-70 Facility PIBSPIBS

Sandibek Nurushev, 1 Oct. Dubna, SPIN Proton Polarimetry at Protvino U-70 Facility Parameters pp H-↑H-↑pD↑ Current, mA P, %  N,  mm  mrad 1.7 T,  s 100, Hz {rep. rate) 1-10 D, atoms/cm 2  s 2  PIBS parameters:

Sandibek Nurushev, 1 Oct. Dubna, SPIN Linac Ural - 30 Number of resonators Length, m Injection-Extraction energy, MeV Radiofrequency, MHz Current pulse amplitude, designed, mA At start Operating Current pulse duration, µs Transverse emittance  ·mm·mrad Momentum spread (at 40 mA), RFQ focusing is applied to the front and end sections of Linac  0.3 Proton Polarimetry at Protvino U-70 Facility

Sandibek Nurushev, 1 Oct. Dubna, SPIN Polarimeter for Linac: p↑+  = p +  (W.G. Weitkamp and W. Haeberli, Nucl. Phys. 83 (1966) 46-54).

Sandibek Nurushev, 1 Oct. Dubna, SPIN Booster-1.5 Injection energy, MeV Number of injection turns Maximum enregy, designed, MeV For injection in U70, GeV For application research Orbit length, m Magnetic field, T Radius of curvature, m Structure periodicity Orbit expansion coefficient Critical energy (kinetic), GeV Superperiod structure, separate functions Pulse packet regime: pulse repetition rate (  32=3+29) Packet frequency, Hz Intensity, p/bunch 30 1 – , (1) – oMoFoDoFoM ·10 11 Proton Polarimetry at Protvino U-70 Facility

Sandibek Nurushev, 1 Oct. Dubna, SPIN Accelerating garmonics Radiofrequency, MHz Acceler. voltage (9 sections ), KV Acceleration time, ms Duration of magnetic cycle,ms Working point (Q x, Q y ), standart High intensity Bunch GeV, ns Momentum 1.32 GeV, % Transverse 1.32 Horizontal,  ·mm·mrad Vertical,  ·mm·mrad Beam pipe aperture hor·vert, cm – (3.85 – 3.80) (3.92 – 3.75) 80 – 100  ·6.1 Proton Polarimetry at Protvino U-70 Facility Booster-1.5 (cont)

Sandibek Nurushev, 1 Oct. Dubna, SPIN Polarimeter for Booster U-1.5

Sandibek Nurushev, 1 Oct. Dubna, SPIN Injection energy, GeV Max. energy, designed, GeV Operating energy, GeV Circumference, m Magnetic field, T Radius of curvature, m Structure periodicity Orbit expansion coefficient Critical energy (kinetic), GeV Superperiod structure, combined functions Cycle repetition rate, s Intensity, p/cycle Accelerating harmonics Number of bunches Vacuum, Tor – 60 – – FoDoFoD’oFoD’oF’oDoFoDo  1.7· · Synchrotron U70 Proton Polarimetry at Protvino U-70 Facility

Sandibek Nurushev, 1 Oct. Dubna, SPIN Radiofrequency, MHz Accel. Volt. (40 stations), MeV Ramping time, s Working point (Q x, Q y ): Standard (I<1·10 13 p/cycle) High intensity bunch 70 GeV, ns Momentum 70 GeV, % Transverse 70 GeV: Horizontal,  ·mm·mrad Vertical,  ·mm·mrad beam pipe aperture, hxv, cm (9.88, 9.82) (9.92, 9.85) x10 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 s for GeV correspondingly. Operaion is foreseen for crossing the critical energy.

Sandibek Nurushev, 1 Oct. Dubna, SPIN 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 s for GeV correspondingly. Operation is foreseen for crossing the critical energy.

Sandibek Nurushev, 1 Oct. Dubna, SPIN

Sandibek Nurushev, 1 Oct. Dubna, SPIN AGS CNI Polarimeter lMeasuring the recoil carbons from lCarbon identification by kinematics cut (banana cut) 60cm Ultra thin Carbon ribbon Target (5 cm long, 3.5  g/cm 2,600  m) beam view Si strip detectors (TOF, E C ) originates from anomalous magnetic moment of p

Sandibek Nurushev, 1 Oct. Dubna, SPIN 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) Yu.P. Gorin et al., Sov. J. Nucl. Phys. 14 (1971) N.I. Bojko et al., IHEP Preprint 70-79, Serpukhov, Assuming A N (  - )= A N (  + )=0.1, I(pp/s)=10 11 one could measure beam polarization with a precision of 5% during 3hrs (  - ) and 0.5hrs (  +).

Sandibek Nurushev, 1 Oct. Dubna, SPIN Summary U70 1.Two Absolute CNI polarimeters (elastic pp and pC on the internal targets) 2.One Relative pion inclusive polarimeter (internal targets) 3.Extraction of the portion of the circulated polarized beam by the bent crystall and polarimetry on this beam U1.5 1.Relative polarimeters on elastic pp or pC - scatterings Linac Ural-30 1.Relative polarimeter based on the elastic p  scattering PIBS 1.Polarimeter based on the Lamb-shift effect.