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Title: Calculating the polarization lifetime from the Thomas-Bargmann-Michel-Telegdi equation

Abstract

It was observed at the Relativistic Heavy Ion Collider that the polarization of the stored beam decays by 0.17 to 3% per hour. This effect could not be simulated up to now since the simulation time for an exact calculation exceeded the computer capacity. To solve this problem the action of the whole arc was considered as one element acting on the spin and not, as before, each optical element in the arc individually (called lattice independent integration). In addition to former simulations the coupling of synchrotron and betatron motions in the beam interaction regions and their action on the polarization were taken into account (called addition of longitudinal dynamics). It is shown that with these two changes the action on the polarization life time can be explained.

Authors:
ORCiD logo
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP)
OSTI Identifier:
1566891
Alternate Identifier(s):
OSTI ID: 1566301
Report Number(s):
BNL-212129-2019-JAAM
Journal ID: ISSN 2469-9888; PRABCJ; 091001
Grant/Contract Number:  
AC02-98CH10886; AC02-05CH11231; SC0012704
Resource Type:
Published Article
Journal Name:
Physical Review Accelerators and Beams
Additional Journal Information:
Journal Name: Physical Review Accelerators and Beams Journal Volume: 22 Journal Issue: 9; Journal ID: ISSN 2469-9888
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS

Citation Formats

Ranjbar, V. H. Calculating the polarization lifetime from the Thomas-Bargmann-Michel-Telegdi equation. United States: N. p., 2019. Web. doi:10.1103/PhysRevAccelBeams.22.091001.
Ranjbar, V. H. Calculating the polarization lifetime from the Thomas-Bargmann-Michel-Telegdi equation. United States. doi:10.1103/PhysRevAccelBeams.22.091001.
Ranjbar, V. H. Sun . "Calculating the polarization lifetime from the Thomas-Bargmann-Michel-Telegdi equation". United States. doi:10.1103/PhysRevAccelBeams.22.091001.
@article{osti_1566891,
title = {Calculating the polarization lifetime from the Thomas-Bargmann-Michel-Telegdi equation},
author = {Ranjbar, V. H.},
abstractNote = {It was observed at the Relativistic Heavy Ion Collider that the polarization of the stored beam decays by 0.17 to 3% per hour. This effect could not be simulated up to now since the simulation time for an exact calculation exceeded the computer capacity. To solve this problem the action of the whole arc was considered as one element acting on the spin and not, as before, each optical element in the arc individually (called lattice independent integration). In addition to former simulations the coupling of synchrotron and betatron motions in the beam interaction regions and their action on the polarization were taken into account (called addition of longitudinal dynamics). It is shown that with these two changes the action on the polarization life time can be explained.},
doi = {10.1103/PhysRevAccelBeams.22.091001},
journal = {Physical Review Accelerators and Beams},
number = 9,
volume = 22,
place = {United States},
year = {2019},
month = {9}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: 10.1103/PhysRevAccelBeams.22.091001

Figures / Tables:

FIG. 1 FIG. 1: RHIC-AGS complex.

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Works referenced in this record:

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