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A P + DEUTERON PROTON POLARIMETER AT 200 MEV.

Description: There has been concern about the analyzing power of the p-Carbon polarimeter at the end of 200 MeV LINAC of BNL. A new polarimeter based on proton-deuteron scattering was installed and we have repeated the calibration of proton-Carbon scattering at 12 degrees and 200 MeV against proton-deuteron scattering. The result is consistent with the value of A=0.62 now used to measure the beam polarization at the end of the LINAC.
Date: June 2, 2002
Creator: HUANG,H.; ROSER,T.; ZELENSKI,A.; KURITA,K.; STEPHENSON,E. & TOOLE,R.
Partner: UNT Libraries Government Documents Department

Bunch profiles in RHIC from CNI polarimeter target scans.

Description: During the RHIC run-4 polarized proton operation, the intensity and polarization profiles were measured by scanning the Coulomb-nuclear interference (CNI) polarimeter targets across the beam. The scans reported here were all performed on flattop at beam momenta {approx}100 GeV/c, and all but one was a vertical scan, since several of the vertical polarimeter targets had broken by the time of the measurements. This note summarizes some analyses of these profiles. Wall current monitor data are compared to these results for one beam and fill.
Date: June 3, 2005
Creator: Spinka, H. M.
Partner: UNT Libraries Government Documents Department

LEP and CEBAF Polarimeters

Description: This paper gives an overview on high energy electron (positron) polarimeters by describing in more detail the plans for the LEP polarimeter and the CEBAF polarimeters. Both LEP and CEBAF will have laser polarimeters. In addition CEBAF will be equipped with a Moller polarimeter (for currents below 1 micro-amp).
Date: September 1, 1988
Creator: Rossmanith, Robert; Burkert, Volker & Placidi, Massimo
Partner: UNT Libraries Government Documents Department

Run-09 pC polarimeter analysis

Description: Analysis of PC polarimeter data at {radical}s = 200 and 500 GeV from Run9 is presented. Final polarization results, fill-by-fill, for blue and yellow beams, as to be used by RHIC experiments (in collisions) are released and collected in http://www4.rcf.bnl.gov/cnipol/pubdocs/Run09Offline/. Global relative systematic uncertainties {delta}P/P (to be considered as correlated from fill to fill) are 4.7% for 100 GeV beams, and 8.3% (12.1%) for blue (yellow) 250 GeV beams. For a product of two beam polarizations P{sub B} {center_dot} P{sub Y} (used in double spin asymmetry measurements) the relative uncertainty {delta}(P{sub B} {center_dot} P{sub Y})/(P{sub B} {center_dot} P{sub Y}) 8.8% for 100 GeV beams and 18.5% for 250 GeV beams. For the average between two beam polarization (P{sub B} + P{sub Y})/2 (used in single spin asymmetry measurements, when data from two polarized beams are combined) the relative uncertainty is 4.4% for 100 GeV beams and 9.2% for 250 GeV beams. Larger uncertainties for 250 GeV beams relate to significant rate related systematic effects experienced in the first part of Run9 (due to thicker targets used and smaller trans. beam size at higher beam energy).
Date: August 1, 2010
Creator: Alekseev, I.; Aschenauer, E.; Atoyan, G.; Bazilevsky, A.; Gill, R.; Huang, H. et al.
Partner: UNT Libraries Government Documents Department

A Study of Inclusive Proton Polarization

Description: The authors propose to measure the polarization of the outgoing proton in the inclusive reaction p + p {yields} p {up_arrow} + X in the region .98 > x{sub R} > .6. The measurements would include beam momenta from p{sub LAB} = 50 GeV/c to p{sub LAB} = 400 GeV/c at t = -.3 (GeV/c){sup 2}, -.8 (GeV/c){sup 2}, -1.4 (GeV/c){sup 2}, and -3.0 (GeV/c){sup 2} over the range .6 < x{sub F} < .95. The experiment would use the existing E313 polarimeter and internal target spectrometer.
Date: January 1, 1975
Creator: Corcoran, M.; Ems, S.C.; Fredericksen, F.; Gray, S.W.; Neal, H.A.; Ogren, H.O. et al.
Partner: UNT Libraries Government Documents Department

Handbook of Accelerator Physics and Engineering (sections 2.7.1 - 2.7.5 and 7.6.2)

Description: The sections written by this author are: 2.7.1- Thomas - BMT equation; 2.2.2- Spinor Algebra; 2.7.3- Spin Rotators and Siberian Snakes; 2.7.4- Ring with Spin Rotator and Siberian Snakes; 2.7.5- Depolarizing Resonances and Spin Flippers; & 7.6.2- Proton Beam Polarimeters
Date: April 19, 1999
Creator: Roser, T.
Partner: UNT Libraries Government Documents Department

Design and Optimization of a Complete Stokes Polarimeter for the MWIR

Description: A figure of merit for optimization of a complete Stokes polarimeter based on its measurement matrix is described from the standpoint of singular value decomposition and analysis of variance. It is applied to optimize a system featuring a rotatable retarder and fixed polarizer, and to study the effects of non-ideal retarder properties. A retardance of 132{degree} (approximately three-eighths wave) and retarder orientation angles of {+-}51.7{degree} and {+-}15.1{degree} are favorable when four measurements are used. An achromatic, form-birefringent retarder for the 3--5 {micro}m spectral region has been fabricated and characterized. The effects of non-idealities in the form-birefringent retarder are moderate, and performance superior to that of a quarter-wave plate is expected.
Date: August 11, 2000
Creator: DERENIAK,E.L.; SABATKE,D.S.; LOCKE,A.M.; DESCOUR,M.R.; SWEATT,WILLIAM C.; GARCIA,J.P. et al.
Partner: UNT Libraries Government Documents Department

COMMISSIONING CNI PROTON POLARIMETERS IN RHIC.

Description: Two polarimeters based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region have been installed and commissioned in the Blue and Yellow rings of RHIC during the first RHIC polarized proton collider run. Each polarimeter consists of ultra-thin carbon targets and six silicon detectors. With newly developed wave form digitizers, they provide fast and reliable polarization information for both rings.
Date: June 2, 2002
Creator: HUANG,H.; BRAVAR,A.; LI,Z.; MACKAY,W.W.; MAKDISI,Y.; RESCIA,S. et al.
Partner: UNT Libraries Government Documents Department

Run05 Proton Beam Polarization Measurements by pC-Polarimeter (ver. 1.1)

Description: The polarization of the proton beams [1, 2] at the Relativistic Heavy Ion Collider (RHIC)[3] RHIC ring. The H-Jet polarimeter is located at the collision point allowing measurements of absolute normalization is provided by the hydrogen polarimeter, which measures over 1 {approx} 2 another measurement rather than measuring the absolute polarization. both beams. Two identical pC-polarimeters are equipped in the yellow and blue rings, where carbon ribbon target, providing fast feedback to beam operations and experiments. The days to obtain {approx} 5% statistical uncertainty (in Run05). Thus, the operation of the carbon is measured using both an atomic beam source hydrogen gas jet (H-Jet)[4, 5] and proton-carbon polarimeters was focused on better control of relative stability between one measurement to statistical accuracy within 20 to 30 seconds using an ultra-thin (typically 6 {approx} 8 {micro}g/cm{sup 2}) the rings are separated. The pC-polarimeter measures relative polarization to a few percent.
Date: July 1, 2008
Creator: Nakagawa,I.; Alekseev, I.; Bazilevsky, A.; Bravar, A.; Bunce, G.; Dhawan, S. et al.
Partner: UNT Libraries Government Documents Department

p-Carbon polarimetry at RHIC.

Description: The polarization measurement through elastic ({rvec p},C) reaction plays a crucial role in the polarized proton beam operation of Relativistic Heavy Ion collider at Brookhaven National Laboratory. As well as measuring the polarization, the unknown analyzing power A{sub N} of elastic ({rvec p},C) is determined as well in combination with the absolute polarization measurement by a H-jet polarimeter. The systematic uncertainty of the Run05 measurements are discussed as well as introducing the experimental apparatus of the polarimeter system.
Date: September 10, 2007
Creator: Nakagawa,I.; Makdisi,Y.; Alekseev, I.; Bazilesky, A.; Bravar, A.; Bunce, G. et al.
Partner: UNT Libraries Government Documents Department

Analysis of AGS E880 polarimeter data at Ggamma = 12.5

Description: Data were collected with the AGS internal (E880) polarimeter at G{gamma} = 12.5 during the FY04 polarized proton run. Measurements were made with forward scintillation counters in coincidence with recoil counter telescopes, permitting an absolute calibration of the polarimeter for both nylon and carbon targets. The results are summarized and they will also be useful for an absolute calibration of the AGS CNI polarimeter at G{gamma} = 12.5.
Date: January 27, 2012
Creator: Cadman, R.V.; Huang, H.; Krueger, K.; Spinka, H. et al.
Partner: UNT Libraries Government Documents Department

POLARIZED PROTON OPERATIONS IN THE AGS AND RHIC.

Description: Polarized proton beam has been accelerated and stored at 100 GeV in Relativistic Heavy Ion Collider (RHIC) to study spin effects in the hadronic reactions. The essential equipment includes four Siberian snakes and eight spin rotators in two RHIC rings, a partial snake in the AGS, fast relative polarimeters, and ac dipoles in the AGS and RHIC. This paper summarizes the performance of RHIC as a polarized proton collider and of AGS as the injector to RHIC.
Date: May 12, 2003
Creator: HUANG,H.; AHRENS,L.; BAI,M.; BEEBE-WANG,J.; ALESSI,J.; ALEKSEEV,I. et al.
Partner: UNT Libraries Government Documents Department

Final Report for Grant DE-FG02-03ER41253

Description: This is the final report of activity under this grant. The polarimeter is built and awaits installation in the HMS in Hall C, now planned for the Spring of 2007. The experiment itself will occur in the second half of 2007. The parameters of the drift chambers have been studied experimentally and found to satisfy our original request.
Date: June 27, 2006
Creator: Perdrisat, Charles F.; Punjabi, Vina; Jones, M. K. & Gilman, R.
Partner: UNT Libraries Government Documents Department

Analysis of AGS E880 polarimeter data at Gy = 12.5.

Description: Data were collected with the AGS internal (E880) polarimeter at G{gamma} = 12.5 during the FY04 polarized proton run. Measurements were made with forward scintillation counters in coincidence with recoil counter telescopes, permitting an absolute calibration of the polarimeter for both nylon and carbon targets. The results are summarized and they will also be useful for an absolute calibration of the AGS CNI polarimeter at G{gamma} = 12.5.
Date: February 23, 2012
Creator: Cadman, R.; Huang, H.; Krueger, K.; Spinka, H.; Underwood, D. (High Energy Physics) & Laboratory), (Brookhaven National
Partner: UNT Libraries Government Documents Department

Measurements of the electromagnetic form factor of the Proton at Jlab

Description: The ratio of the proton's elastic electromagnetic form factors G{sub E{sub p}}/G{sub M{sub p}} was obtained by measuring P{sub t} and P{sub {ell}}, the transverse and longitudinal recoil proton polarization, respectively. For the elastic reaction {rvec e}p {yields} e{rvec p}, G{sub E{sub p}}/G{sub M{sub p}} is proportional to P{sub t}/P{sub {ell}}. The simultaneous measurement of P{sub t} and P{sub {ell}} in a polarimeter reduces systematic uncertainties. The results for the ratio G{sub E{sub p}}/G{sub M{sub p}} measured in Hall A so far show a systematic decrease with increasing Q{sup 2}, indicating for the first time a definite difference in the distribution of charge and magnetization in the proton. Together these experiments cover the Q{sub 2}- range of 0.5 to 5.6 GeV{sup 2}. A new experiment is currently being prepared, to extend the Q{sup 2}-range to 9 GeV{sup 2} in Hall C.
Date: April 1, 2003
Creator: Punjabi, Vina & Perdrisat, Charles
Partner: UNT Libraries Government Documents Department

Conceptual design of a proton polarimeter for RHIC

Description: A two-arm pion polarimeter utilizing toroidal magnets is being considered for use with the polarized protons beam at RHIC. The system will enable measurements of beam polarization at all RHIC energies from injection to flattop. This is a necessary diagnostic tool for tuning the RHIC snake magnets and other polarization controlling elements. Toroidal magnets constrain the pion trajectories allowing the device to be compact so that it can fit within the limited space available. A viable magnet design has been completed and suitable target configuration and operating scenario have been identified.
Date: December 1, 1996
Creator: Alekseev, I.; Belikov, N. & Bunce, G.
Partner: UNT Libraries Government Documents Department

Calibration of the stellar X-ray polarimeter

Description: The Stellar X-Ray Polarimeter (SXRP) will be more than an order of magnitude more sensitive than any previous x-ray polarimeter in the 2-15 keV energy band. The SXRP is a focal plane detector for a Danish-Russian SODART telescope, which will be launched on the Russian Spectrum-X-Gamma (SXG) mission. The SXRP exploits the polarization dependence of Bragg reflection from a graphite crystal, and of Thomson scattering from a target of metallic lithium. The SXRP flight model (FM) was calibrated at a facility at Lawrence Livermore National Laboratory (LLNL) equipped with polarized and unpolarized x-ray sources producing x-rays in the band pass for the graphite and the lithium scatterers. By adjusting the orientation of the SXRP with respect to the incident x-ray beam, it was possible to simulate the converging beam from a SODART telescope and to measure the SXRP response to telescope pointing errors. In this paper we describe the SXRP-FM calibration and present results for the graphite polarimeter.
Date: July 1, 1997
Creator: Tomsick, J.
Partner: UNT Libraries Government Documents Department

Note on RHIC polarimetry.

Description: For physics measurements with polarized colliding beams, beam polarizations and relative luminosities must both be determined. Predictions for spin observables of many interesting physics processes at RHIC are quite small in magnitude. This requires high statistics measurements of relative luminosities and careful control of systematic errors. Discussions about the polarized beams at RHIC often presume that the polarization and intensity of each bunch within a will be known quite well from measurements by the RHIC polarimeters. The purpose of this note is to give a description of the knowledge that can actually be obtained from these polarimeters.
Date: November 12, 1999
Creator: Spinka, H.
Partner: UNT Libraries Government Documents Department

Optimization of retardance for a complete Stokes polarimeter

Description: The authors present two figures of merit based on singular value decomposition which can be used to assess the noise immunity of a complete Stokes polarimeter. These are used to optimize a polarimeter consisting of a rotatable retarder and fixed polarizer. A retardance of 132{degree} (approximately three eights wave) and retarder orientation angles of {+-}51.7{degree} and {+-}15.1{degree} are found to be optimal when four measurements are used. Use of this retardance affords a factor of 1.5 improvement in signal-to-noise ratio over systems employing a quarter wave plate. A geometric means of visualizing the optimization process is discussed, and the advantages of the use of additional measurements are investigated. No advantage of using retarder orientation angles spaced uniformly through 360{degree} is found over repeated measurements made at the four angles given previously.
Date: January 13, 2000
Creator: Sabatke, D.S.; Descour, M.R.; Dereniak, E.L.; Sweatt, W.C.; Kemme, S.A. & Phipps, G.S.
Partner: UNT Libraries Government Documents Department

A photon calorimeter using lead tungstate crystals for the CEBAF HAll A Compton polarimeter

Description: A new Compton polarimeter is built on the CEBAF Hall A electron beam line. Performances of 10% resolution and 1% calibration are required for the photon calorimeter of this polarimeter. This calorimeter is built with lead tungstate scintillators coming from the CMS electromagnetic calorimeter R&D. Beam tests of this detector have been made using the tagged photon beam line at MAMI, Mainz, and a resolution of 1.76%+2.75%/v+0.41%/E has been measured.
Date: May 1, 2000
Creator: Neyret, D.; Pussieux, T.; Auger, T.; Baylac, M.; Burtin, E.; Cavata, C. et al.
Partner: UNT Libraries Government Documents Department

A NEW RELATIVE PROTON POLARIMETER FOR RHIC.

Description: An innovative polarimeter based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region has been installed and commissioned in the Blue ring of RHIC during the first RHIC polarized proton commissioning in September, 2000. The polarimeter consists of ultra-thin carbon targets and four silicon detectors. All elements are in a 1.6 meter vacuum chamber. This paper summarizes the polarimeter design issues and recent commissioning results.
Date: June 18, 2001
Creator: HUANG,H.; ALEKSEEV,I.; BUNCE,G.; BRUNER,N.; DESHPANDE,A.; GOTO,Y. et al.
Partner: UNT Libraries Government Documents Department

Analysis of low energy AGS polarimeter data and potential consequences for RHIC spin physics.

Description: The small asymmetries measured at G{sub {gamma}} = 7.5 during the RHIC spin commissioning were a serious concern. In earlier runs, asymmetries double those from the spin commissioning time (September 2000) had sometimes been observed, and there had been few changes to the AGS polarimeter hardware or operating conditions. Recently, the observed changes in the asymmetries measured at G{sub {gamma}} = 7:5 have been ascribed to contamination of the carbon target asymmetry with that from the fishline target and vice-versa, because of the sizeable beam spot size compared to the separation of the targets. This note addresses this hypothesis using the observed asymmetries. This problem could directly impact spin physics at RHIC.
Date: June 22, 2001
Creator: Cadman, R.; Krueger, K.; Spinka, H.; Underwood, D.; Yokosawa, A. & Huang, H.
Partner: UNT Libraries Government Documents Department

Proceedings of RIKEN BNL Research Center workwhop on RHIC spin

Description: This RHIC Spin Workshop is the 1999 annual meeting of the RHIC Spin Collaboration, and the second to be hosted at Brookhaven and sponsored by the RIKEN BNL Research Center. The previous meetings were at Brookhaven (1998), Marseille (1996), MIT in 1995, Argonne 1994, Tucson in 1991, and the Polarized Collider Workshop at Penn State in 1990. As noted last year, the Center provides a home for combined work on spin by theorists, experimenters, and accelerator physicists. This proceedings, as last year, is a compilation of 1 page summaries and 5 selected transparencies for each speaker. It is designed to be available soon after the workshop is completed. Speakers are welcome to include web or other references for additional material. The RHIC spin program and RHIC are rapidly becoming reality. RHIC has completed its first commissioning run, as described here by Steve Peggs. The first Siberian Snake for spin has been completed and is being installed in RHIC. A new polarized source from KEK and Triumf with over 1 milliampere of polarized H{sup minus} is being installed, described by Anatoli Zelenski. They have had a successful test of a new polarimeter for RHIC, described by Kazu Kurita and Haixin Huang. Spin commissioning is expected next spring (2000), and the first physics run for spin is anticipated for spring 2001. The purpose of the workshop is to get everyone together about once per year and discuss goals of the spin program, progress, problems, and new ideas. They also have many separate regular forums on spin. There are spin discussion sessions every Tuesday, now organized by Naohito Saito and Werner Vogelsang. The spin discussion schedule and copies of presentations are posted on http://riksg01.rhic.bnl.gov/rsc. Speakers and other spinners are encouraged to come to BNL and to lead a discussion on your favorite idea. ...
Date: October 6, 1999
Creator: Soffer, J.
Partner: UNT Libraries Government Documents Department

Electron beam polarimetry

Description: Along with its well known charge and mass, the electron also carries an intrinsic angular momentum, or ''spin.'' The rules of quantum mechanics allow one to measure only the probability that the electron spin is in one of two allowed spin states. When a beam carries a net excess of electrons in one of these two allowed spin states, the beam is said to be ''polarized.'' The beam polarization may be measured by observing a sufficient number of electrons scattered by a spin-dependent interaction. For electrons, the useful scattering processes involve coulomb scattering by heavy nuclei, or scattering from either polarized photons or other polarized electrons (known as Mott, Compton, or Moller scattering, respectively). In this tutorial, the authors briefly review how beam polarization is measured through a general scattering process, followed by a discussion of how the three scattering processes above are used to measure electron beam polarization. Descriptions of electron polarimeters based on the three scattering processes will be given.
Date: January 1, 1998
Creator: Sinclair, Charles K.
Partner: UNT Libraries Government Documents Department