Spin asymmetries and correlations in {lambda}pair production through the radiative return method
Abstract
Exclusive baryon pair production through the radiative return is a unique tool to determine the electric and the magnetic form factors in the timelike region over a wide range of energies. The decay of {lambda}baryons into p+{pi}{sup } can be used to measure their spin and to analyze spinspin correlations in the {lambda}{lambda} system. We evaluate the spin dependent hadronic tensor, which describes this reaction, calculate the corresponding cross section for e{sup +}e{sup }{yields}{lambda}{lambda} and e{sup +}e{sup }{yields}{lambda}{lambda}{gamma} with subsequent decays of {lambda} and {lambda} and present a compact formula for the correlated distribution. We demonstrate that the relative phase between the electric and the magnetic form factor can be determined in this analysis by considering singlespin asymmetries and correlated decay distributions. The reaction is implemented in the event generator PHOKHARA. It is demonstrated that the relative phase can be measured with the event sample presently accumulated at B factories.
 Authors:
 Institute of Physics, University of Silesia, PL40007 Katowice (Poland)
 (Germany)
 Publication Date:
 OSTI Identifier:
 21020286
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevD.75.074026; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; CORRELATIONS; CROSS SECTIONS; DISTRIBUTION; ELECTRONPOSITRON INTERACTIONS; ELECTRONS; EXCLUSIVE INTERACTIONS; FORM FACTORS; HADRONIC PARTICLE DECAY; LAMBDA BARYONS; PAIR PRODUCTION; PIONS MINUS; POSITRONS; SPIN; TENSORS
Citation Formats
Czyz, Henryk, Grzelinska, Agnieszka, Kuehn, Johann H., and Institut fuer Theoretische Teilchenphysik, Universitaet Karlsruhe, D76128 Karlsruhe. Spin asymmetries and correlations in {lambda}pair production through the radiative return method. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.074026.
Czyz, Henryk, Grzelinska, Agnieszka, Kuehn, Johann H., & Institut fuer Theoretische Teilchenphysik, Universitaet Karlsruhe, D76128 Karlsruhe. Spin asymmetries and correlations in {lambda}pair production through the radiative return method. United States. doi:10.1103/PHYSREVD.75.074026.
Czyz, Henryk, Grzelinska, Agnieszka, Kuehn, Johann H., and Institut fuer Theoretische Teilchenphysik, Universitaet Karlsruhe, D76128 Karlsruhe. Sun .
"Spin asymmetries and correlations in {lambda}pair production through the radiative return method". United States.
doi:10.1103/PHYSREVD.75.074026.
@article{osti_21020286,
title = {Spin asymmetries and correlations in {lambda}pair production through the radiative return method},
author = {Czyz, Henryk and Grzelinska, Agnieszka and Kuehn, Johann H. and Institut fuer Theoretische Teilchenphysik, Universitaet Karlsruhe, D76128 Karlsruhe},
abstractNote = {Exclusive baryon pair production through the radiative return is a unique tool to determine the electric and the magnetic form factors in the timelike region over a wide range of energies. The decay of {lambda}baryons into p+{pi}{sup } can be used to measure their spin and to analyze spinspin correlations in the {lambda}{lambda} system. We evaluate the spin dependent hadronic tensor, which describes this reaction, calculate the corresponding cross section for e{sup +}e{sup }{yields}{lambda}{lambda} and e{sup +}e{sup }{yields}{lambda}{lambda}{gamma} with subsequent decays of {lambda} and {lambda} and present a compact formula for the correlated distribution. We demonstrate that the relative phase between the electric and the magnetic form factor can be determined in this analysis by considering singlespin asymmetries and correlated decay distributions. The reaction is implemented in the event generator PHOKHARA. It is demonstrated that the relative phase can be measured with the event sample presently accumulated at B factories.},
doi = {10.1103/PHYSREVD.75.074026},
journal = {Physical Review. D, Particles Fields},
number = 7,
volume = 75,
place = {United States},
year = {Sun Apr 01 00:00:00 EDT 2007},
month = {Sun Apr 01 00:00:00 EDT 2007}
}

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