Exploring Hyperon Structure with Electromagnetic Transverse Densities

Hiller Blin, Astrid N.; Alarcon, Jose Manuel; Vicente Vacas, Manuel J.; Weiss, Christian

doi:10.1007/s00601-018-1434-3

Exploring Hyperon Structure with Electromagnetic Transverse Densities

Journal Article · Wed Jul 18 00:00:00 EDT 2018 · Few-Body Systems

DOI:https://doi.org/10.1007/s00601-018-1434-3· OSTI ID:1462191

Hiller Blin, Astrid N. ^[1]; Alarcon, Jose Manuel ^[2]; Vicente Vacas, Manuel J. ^[3]; Weiss, Christian ^[2]

Johannes Gutenberg Univ., Mainz (Germany)
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Univ. de Valencia-CSIC, Valencia (Spain)

Here, we explore the structure of the spin-1/2 flavor-octet baryons (hyperons) through their electromagnetic transverse densities. The transverse densities describe the distribution of charge and magnetization at fixed light-front time and enable a spatial representation of the baryons as relativistic systems. At peripheral distances b~1/M_π the transverse densities are computed using a new method that combines chiral effective field theory (χEFT) and dispersion analysis. The peripheral isovector densities arise from two-pion exchange, which includes the ρ resonance through elastic unitarity. The isoscalar densities are estimated from vector meson exchange (ω,Φ). We find that the “pion cloud” in the charged Σ hyperons is comparable to the nucleon, while in the Ξ it is suppressed. The Λ–Σ⁰ transition density is pure isovector and represents a clear manifestation of peripheral two-pion dynamics.

View Accepted Manuscript (DOE)

Research Organization:: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)

Grant/Contract Number:: AC05-06OR23177

OSTI ID:: 1462191

Alternate ID(s):: OSTI ID: 22765586

Report Number(s):: DOE/OR/23177--4343; JLAB-THY--18-2641; arXiv:1802.00479; PII: 1434

Journal Information:: Few-Body Systems, Journal Name: Few-Body Systems Journal Issue: 6 Vol. 59; ISSN 0177-7963

Publisher:: SpringerCopyright Statement

Country of Publication:: United States

Language:: English

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