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Title: The TRIC Experiment: A P-even Time-Reversal Invariance Test at COSY

Abstract

At the cooler synchrotron COSY at Juelich a novel (P-even, T-odd) true null test was proposed, that is supposed to measure the time-reversal invariance sensitive observable, the total cross-section correlation Ay,xz, to an accuracy of 10-6. This observable is measured in a transmission experiment of a circulating vector polarized (Py) proton beam through an internal tensor polarized (Pxz) atomic deuteron target. The experiment uses the COSY facility as an accelerator, an ideal forward spectrometer, and as a detector. At present the experimental focus lies on the development of a precise current measurement via a Beam-Current-Transformer (BCT), its precise read-out and analysis. So far, we succeeded to meet the BCT's accuracy specification. With the help of this accurate current measurement the development of a proper long living proton beam in COSY at the optimum energy, where the experiment has its highest sensitivity, is in progress.

Authors:
 [1]
  1. Helmholtz Institut fuer Strahlen- und Kernphysik, University Bonn, Nussallee 14-16, 53115 Bonn (Germany)
Publication Date:
OSTI Identifier:
20726701
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 796; Journal Issue: 1; Conference: LEAP '05: 8. international conference on low energy antiproton physics, Bonn (Germany), 16-22 May 2005; Other Information: DOI: 10.1063/1.2130133; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; BEAM CURRENTS; CORRELATIONS; COSY STORAGE RING; CP INVARIANCE; CPT THEOREM; DEUTERIUM TARGET; HEAT EXCHANGERS; PROTON BEAMS; READOUT SYSTEMS; SENSITIVITY; SPECIFICATIONS; T INVARIANCE; TRANSFORMERS; TRANSMISSION; VECTORS

Citation Formats

Eversheim, P.D. The TRIC Experiment: A P-even Time-Reversal Invariance Test at COSY. United States: N. p., 2005. Web. doi:10.1063/1.2130133.
Eversheim, P.D. The TRIC Experiment: A P-even Time-Reversal Invariance Test at COSY. United States. doi:10.1063/1.2130133.
Eversheim, P.D. 2005. "The TRIC Experiment: A P-even Time-Reversal Invariance Test at COSY". United States. doi:10.1063/1.2130133.
@article{osti_20726701,
title = {The TRIC Experiment: A P-even Time-Reversal Invariance Test at COSY},
author = {Eversheim, P.D.},
abstractNote = {At the cooler synchrotron COSY at Juelich a novel (P-even, T-odd) true null test was proposed, that is supposed to measure the time-reversal invariance sensitive observable, the total cross-section correlation Ay,xz, to an accuracy of 10-6. This observable is measured in a transmission experiment of a circulating vector polarized (Py) proton beam through an internal tensor polarized (Pxz) atomic deuteron target. The experiment uses the COSY facility as an accelerator, an ideal forward spectrometer, and as a detector. At present the experimental focus lies on the development of a precise current measurement via a Beam-Current-Transformer (BCT), its precise read-out and analysis. So far, we succeeded to meet the BCT's accuracy specification. With the help of this accurate current measurement the development of a proper long living proton beam in COSY at the optimum energy, where the experiment has its highest sensitivity, is in progress.},
doi = {10.1063/1.2130133},
journal = {AIP Conference Proceedings},
number = 1,
volume = 796,
place = {United States},
year = 2005,
month =
}
  • At the cooler synchrotron COSY at Juelich a novel (P-even, T-odd) true null test of time-reversal invariance (TRI) was proposed and accepted that allows to measure TRI to an accuracy of 10{sup {minus}6}. The observable of interest is the total cross-section asymmetry A{sub y,xz}, which is measured in an transmission experiment of a circulating vector polarized proton beam through an internal tensor polarized atomic deuteron target. This experiment uses the COSY facility in three respects: As an accelerator, as an ideal forward spectrometer and as an detector. {copyright} {ital 1998 American Institute of Physics.}
  • At the cooler synchrotron COSY at Juelich a novel (P-even, T-odd) true null test of time-reversal invariance (TRI) was proposed and accepted that allows to measure TRI to an accuracy of 10{sup -6}. The observable of interest is the total cross-section asymmetry A{sub y,xz}, which is measured in an transmission experiment of a circulating vector polarized proton beam through an internal tensor polarized atomic deuteron target. This experiment uses the COSY facility in three respects: As an accelerator, as an ideal forward spectrometer and as an detector.
  • A new measurement of the parity-conserving, time reversal noninvariant (PC TRNI) fivefold correlation has been performed at Triangle Universities Nuclear Laboratory, using 6.57 MeV polarized neutrons and a cryogenically aligned holmium target. The PC TRNI spin correlation coefficient {ital A}{sub 5} is measured to be (1.1{plus_minus}2.3){times}10{sup {minus}5}, consistent with time reversal invariance. A bound of 3.8{times}10{sup {minus}3} (99% confidence) is extracted for the ratio of PC TRNI to TRI nuclear matrix elements.
  • The development and implementation of a 10 MHz neutron production target and detector system are presented. The system has been used in a test of parity-even time reversal invariance in neutron transmission through an aligned target. Neutrons were produced via the D(d,n){sup 3}He reaction using a liquid nitrogen cooled deuterium gas cell. The cryogenic cell required temperature stabilization for minimization of systematic effects. Two four-detector arrays of neutron detectors were developed for 0{degrees} transmission measurements and flux monitoring. The system allowed transmission asymmetries to be measured to accuracies better than 10{sup -6} in a parity-conserving test of time reversal invariance.
  • We have recently carried out the most precise direct test of parity-even time reversal invariance in nuclear physics. The experiment involves searching for the P-even, T-odd spin correlation a - (I x k) (I - k) in the neutron-nucleus: forward scattering amplitude. The measurement uses 6 MeV polarized neutrons transmitted through a cryogenically aligned rotating holmiurn target. The amplitude of the T-odd neutron asymmetry was measured to be 11 {plus_minus} 10 X 10{sub -7} consistent with time reversal invartance. Following the recent work of Engel et al, the asymmetry can be analyzed in terms of a bound on a TVPCmore » p exchange coupling. I will compare our bounds to those obtained in detailed balance measurements, and to the indirect bounds inferred from atomic and neutron electric dipole moment measurements. I will discuss prospects for improving these bounds by taking advantage of the large enhancements associated with compound nucleus resonances.« less