Measurement of the recoil polarization in the p((e)over-right-arrow, e′(p)over-right-arrow)π0 reaction at the Δ(1232) resonance

被引：103

作者：

Pospischil, T ^{[1
]}

Bartsch, P

Baumann, D

Bermuth, J

Böhm, R

Bohinc, K

Derber, S

Ding, M

Distler, M

Drechsel, D

Elsner, D

Ewald, I

Friedrich, J

Friedrich, JM

Geigers, R

Hedicke, S

Jennewein, P

Kahrau, M

Kamalov, SS

Klein, F

Krygier, KW

Lac, J

Liesenfeld, A

McIntyre, J

Merkel, H

Merle, P

Müller, U

Neuhausen, R

Potokar, M

Ransome, RD

Rohe, D

Rosner, G

Schmieden, H

Seimetz, M

Sirca, S

Sick, I

Süle, A

Tiator, L

Wagner, A

Walcher, T

Warren, GA

Weis, M

机构：

[1] Univ Mainz, Inst Kernphys, D-55099 Mainz, Germany

[2] Univ Mainz, Inst Phys, D-55099 Mainz, Germany

[3] Univ Ljubljana, Jozef Stefan Inst, SI-1001 Ljubljana, Slovenia

[4] Rutgers State Univ, Piscataway, NJ USA

[5] Univ Basel, Dept Phys & Astron, CH-4056 Basel, Switzerland

[6] Joint Inst Nucl Res Dubna, Theoret Phys Lab, Dubna, Russia

来源：

PHYSICAL REVIEW LETTERS | 2001年 / 86卷 / 14期

关键词：

D O I：

10.1103/PhysRevLett.86.2959

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The recoil proton polarization has been measured in the p((e) over right arrow, e(1)(p) over right arrow)pi (0) reaction in parallel kinematics around W = 1232 MeV, Q(2) = 0.121 (GeV/c)(2) and epsilon = 0.718 using the polarized cw electron beam of the Mainz Microtron. All three proton polarization components, P-x/P-e = (-11.4 +/- 1.3 +/- 1.4)%, P-y = (-43.1 +/- 1.3 +/- 2.2)%, and P-z/P-e = (56.2 +/- 1.5 +/- 2.6)%, could be measured simultaneously. The Coulomb quadrupole to magnetic dipole ratio, CMR = (-6.4 +/- 0.7(stat) +/- 0.8(syst))%, was determined from P-x in the framework of the Mainz Unitary Isobar Model. The consistency among the reduced polarizations and the extraction of the ratio of longitudinal-to-transverse response is discussed.

引用

页码：2959 / 2962

页数：4

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