Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis
Abstract
The baryon electromagnetic form factors are expressed in terms of twodimensional densities describing the distribution of charge and magnetization in transverse space at fixed lightfront time. In this paper, we calculate the transverse densities of the spin1/2 flavoroctet baryons at peripheral distances b=O(M$$1\atop{π}$$) using methods of relativistic chiral effective field theory (χ EFT) and dispersion analysis. The densities are represented as dispersive integrals over the imaginary parts of the form factors in the timelike region (spectral functions). The isovector spectral functions on the twopion cut t > 4 M$$2\atop{π}$$ are calculated using relativistic χEFT including octet and decuplet baryons. The χEFT calculations are extended into the ρ meson mass region using an N/D method that incorporates the pion electromagnetic form factor data. The isoscalar spectral functions are modeled by vector meson poles. We compute the peripheral charge and magnetization densities in the octet baryon states, estimate the uncertainties, and determine the quark flavor decomposition. Finally, the approach can be extended to baryon form factors of other operators and the moments of generalized parton distributions.
 Authors:
 Univ. of Bonn (Germany). Bethe Center for Theoretical Physics. Helmholtz Inst. for Radiation and Nuclear Physics; Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States). Theory Center
 Univ. of Valencia (Spain). Dept. of Theoretical Physics. Inst. for Corpuscular Physics (IFIC)
 Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States). Theory Center
 Publication Date:
 Research Org.:
 Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Univ. of Bonn (Germany); Univ. of Valencia (Spain)
 Sponsoring Org.:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26); German Research Foundation (DFG); Ministry of Economy, Industry and Competitiveness (MINECO) (Spain); European Commission (EC); Generalitat Valenciana
 OSTI Identifier:
 1356984
 Report Number(s):
 JLABTHY172432
Journal ID: ISSN 03759474; PII: S0375947417301185; TRN: US1702506
 Grant/Contract Number:
 AC0506OR23177; CRC 110; FPA201340483P; FIS201451948C22P; SEV20140398; PROMETEOII/2014/0068
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nuclear Physics. A
 Additional Journal Information:
 Journal Volume: 964; Journal ID: ISSN 03759474
 Publisher:
 Elsevier
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Electromagnetic form factors; Chiral lagrangians; Dispersion relations; Hyperons; Charge distribution
Citation Formats
Alarcón, J. M., Hiller Blin, A. N., Vicente Vacas, M. J., and Weiss, C. Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis. United States: N. p., 2017.
Web. doi:10.1016/j.nuclphysa.2017.05.002.
Alarcón, J. M., Hiller Blin, A. N., Vicente Vacas, M. J., & Weiss, C. Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis. United States. doi:10.1016/j.nuclphysa.2017.05.002.
Alarcón, J. M., Hiller Blin, A. N., Vicente Vacas, M. J., and Weiss, C. 2017.
"Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis". United States.
doi:10.1016/j.nuclphysa.2017.05.002.
@article{osti_1356984,
title = {Peripheral transverse densities of the baryon octet from chiral effective field theory and dispersion analysis},
author = {Alarcón, J. M. and Hiller Blin, A. N. and Vicente Vacas, M. J. and Weiss, C.},
abstractNote = {The baryon electromagnetic form factors are expressed in terms of twodimensional densities describing the distribution of charge and magnetization in transverse space at fixed lightfront time. In this paper, we calculate the transverse densities of the spin1/2 flavoroctet baryons at peripheral distances b=O(M$1\atop{π}$) using methods of relativistic chiral effective field theory (χ EFT) and dispersion analysis. The densities are represented as dispersive integrals over the imaginary parts of the form factors in the timelike region (spectral functions). The isovector spectral functions on the twopion cut t > 4 M$2\atop{π}$ are calculated using relativistic χEFT including octet and decuplet baryons. The χEFT calculations are extended into the ρ meson mass region using an N/D method that incorporates the pion electromagnetic form factor data. The isoscalar spectral functions are modeled by vector meson poles. We compute the peripheral charge and magnetization densities in the octet baryon states, estimate the uncertainties, and determine the quark flavor decomposition. Finally, the approach can be extended to baryon form factors of other operators and the moments of generalized parton distributions.},
doi = {10.1016/j.nuclphysa.2017.05.002},
journal = {Nuclear Physics. A},
number = ,
volume = 964,
place = {United States},
year = 2017,
month = 5
}

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