The electromagnetic SigmatoLambda hyperon transition form factors at low energies
Abstract
Using dispersion theory the lowenergy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the twopionSigmaLambda amplitudes are determined from relativistic nexttoleadingorder (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole lowenergy region. The magnetic transition form factor depends strongly on one not very well determined lowenergy constant of the NLO Lagrangian. Furthermore, one obtains reasonable predictive power if this lowenergy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR).
 Authors:
 Uppsala Univ., Uppsala (Sweden); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
 Uppsala Univ., Uppsala (Sweden)
 Publication Date:
 Research Org.:
 Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1369457
 Report Number(s):
 JLABTHY172510; DOE/OR/231774186; arXiv:1701.09130
Journal ID: ISSN 14346001; PII: 860
 Grant/Contract Number:
 AC0506OR23177
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 European Physical Journal. A
 Additional Journal Information:
 Journal Volume: 53; Journal Issue: 6; Journal ID: ISSN 14346001
 Publisher:
 Springer
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Granados, Carlos, Leupold, Stefan, and Perotti, Elisabetta. The electromagnetic SigmatoLambda hyperon transition form factors at low energies. United States: N. p., 2017.
Web. doi:10.1140/epja/i2017123244.
Granados, Carlos, Leupold, Stefan, & Perotti, Elisabetta. The electromagnetic SigmatoLambda hyperon transition form factors at low energies. United States. doi:10.1140/epja/i2017123244.
Granados, Carlos, Leupold, Stefan, and Perotti, Elisabetta. Fri .
"The electromagnetic SigmatoLambda hyperon transition form factors at low energies". United States.
doi:10.1140/epja/i2017123244. https://www.osti.gov/servlets/purl/1369457.
@article{osti_1369457,
title = {The electromagnetic SigmatoLambda hyperon transition form factors at low energies},
author = {Granados, Carlos and Leupold, Stefan and Perotti, Elisabetta},
abstractNote = {Using dispersion theory the lowenergy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the twopionSigmaLambda amplitudes are determined from relativistic nexttoleadingorder (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole lowenergy region. The magnetic transition form factor depends strongly on one not very well determined lowenergy constant of the NLO Lagrangian. Furthermore, one obtains reasonable predictive power if this lowenergy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR).},
doi = {10.1140/epja/i2017123244},
journal = {European Physical Journal. A},
number = 6,
volume = 53,
place = {United States},
year = {Fri Jun 09 00:00:00 EDT 2017},
month = {Fri Jun 09 00:00:00 EDT 2017}
}
Web of Science

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