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Title: Baryon masses and σ terms in SU(3) BChPT×1/N c

Baryon masses and nucleon $$\sigma$$ terms are studied with the effective theory that combines the chiral and $$1/N_c$$ expansions for three flavors. In particular the connection between the deviation of the Gell-Mann-Okubo relation and the $$\sigma$$ term associated with the scalar density $$\bar u u+\bar d d-2\bar s s$$ is emphasized. The latter is at lowest order related to a mass combination whose low value has given rise to a $$\sigma$$ term puzzle. It is shown that while the nucleon $$\sigma$$ terms have a well behaved low energy expansion, that mass combination is affected by large higher order corrections non-analytic in quark masses. Lastly, adding to the analysis lattice QCD baryon masses, it is found that $$\sigma_{\pi N}=69(10)$$~MeV and $$\sigma_s$$ has natural magnitude within its relative large uncertainty.
 [1] ;  [2] ;  [2]
  1. Hampton Univ., Hampton, VA (United States). Dept. of Physics
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Publication Date:
Report Number(s):
JLAB-THY-18-2679; DOE/OR/-23177-4397
Journal ID: ISSN 0370-2693; PII: S0370269318303484
Grant/Contract Number:
AC05-06OR23177; FPA2016-77313-P; PHY-1307413; PHY-1613951
Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 781; Journal Issue: C; Journal ID: ISSN 0370-2693
Research Org:
Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26); National Science Foundation (NSF); European Commission (EC)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Sigma terms; Nucleon mass; Baryon masses; Gell-Mann–Okubo; mass formula
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1454732