Up-down quark mass difference

Couplings of pions to nucleons or isobars and low-energy nucleon-nucleon scattering

Zongjian Cao, W. Y.P. Hwang

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We investigate effects of the up-down quark mass difference on the couplings of pions to nucleons or isobars. The calculated NN and N couplings are used to derive the long-range one-pion-exchange potential and the intermediate-range attraction for the three different cases: p-p, n-p, and n-n. The resultant potentials are then used to determine numerically the low-energy scattering parameters, including both the scattering length a and the effective range r. Our results indicate that a reasonable up-down quark mass difference such as 10 MeV yields a value for |app|-|ann| of about + 0.6 fm, which is sizable from the experimental point of view. Our results also suggest that the large observed value for |anp|-|ann| can be understood primarily as a manifestation of the pion mass difference. [NUCLEAR REACTIONS Application of quark models to nuclear physics; effects of the up-down quark mass difference on couplings of pions to nucleons or isobars; charge dependence and charge symmetry breaking in low energy nucleon-nucleon scattering.]

Original languageEnglish (US)
Pages (from-to)1-12
Number of pages12
JournalPhysical Review C
Volume29
Issue number1
DOIs
StatePublished - Jan 1 1984

Fingerprint

nucleon-nucleon scattering
isobars
nucleons
pions
quarks
energy
nuclear physics
quark models
scattering
attraction
broken symmetry

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

Cite this

Up-down quark mass difference : Couplings of pions to nucleons or isobars and low-energy nucleon-nucleon scattering. / Cao, Zongjian; Hwang, W. Y.P.

In: Physical Review C, Vol. 29, No. 1, 01.01.1984, p. 1-12.

Research output: Contribution to journalArticle

@article{d7681f3419ab42d2b19af69ffb0149e5,
title = "Up-down quark mass difference: Couplings of pions to nucleons or isobars and low-energy nucleon-nucleon scattering",
abstract = "We investigate effects of the up-down quark mass difference on the couplings of pions to nucleons or isobars. The calculated NN and N couplings are used to derive the long-range one-pion-exchange potential and the intermediate-range attraction for the three different cases: p-p, n-p, and n-n. The resultant potentials are then used to determine numerically the low-energy scattering parameters, including both the scattering length a and the effective range r. Our results indicate that a reasonable up-down quark mass difference such as 10 MeV yields a value for |app|-|ann| of about + 0.6 fm, which is sizable from the experimental point of view. Our results also suggest that the large observed value for |anp|-|ann| can be understood primarily as a manifestation of the pion mass difference. [NUCLEAR REACTIONS Application of quark models to nuclear physics; effects of the up-down quark mass difference on couplings of pions to nucleons or isobars; charge dependence and charge symmetry breaking in low energy nucleon-nucleon scattering.]",
author = "Zongjian Cao and Hwang, {W. Y.P.}",
year = "1984",
month = "1",
day = "1",
doi = "10.1103/PhysRevC.29.1",
language = "English (US)",
volume = "29",
pages = "1--12",
journal = "Physical Review C - Nuclear Physics",
issn = "0556-2813",
publisher = "American Physical Society",
number = "1",

}

TY - JOUR

T1 - Up-down quark mass difference

T2 - Couplings of pions to nucleons or isobars and low-energy nucleon-nucleon scattering

AU - Cao, Zongjian

AU - Hwang, W. Y.P.

PY - 1984/1/1

Y1 - 1984/1/1

N2 - We investigate effects of the up-down quark mass difference on the couplings of pions to nucleons or isobars. The calculated NN and N couplings are used to derive the long-range one-pion-exchange potential and the intermediate-range attraction for the three different cases: p-p, n-p, and n-n. The resultant potentials are then used to determine numerically the low-energy scattering parameters, including both the scattering length a and the effective range r. Our results indicate that a reasonable up-down quark mass difference such as 10 MeV yields a value for |app|-|ann| of about + 0.6 fm, which is sizable from the experimental point of view. Our results also suggest that the large observed value for |anp|-|ann| can be understood primarily as a manifestation of the pion mass difference. [NUCLEAR REACTIONS Application of quark models to nuclear physics; effects of the up-down quark mass difference on couplings of pions to nucleons or isobars; charge dependence and charge symmetry breaking in low energy nucleon-nucleon scattering.]

AB - We investigate effects of the up-down quark mass difference on the couplings of pions to nucleons or isobars. The calculated NN and N couplings are used to derive the long-range one-pion-exchange potential and the intermediate-range attraction for the three different cases: p-p, n-p, and n-n. The resultant potentials are then used to determine numerically the low-energy scattering parameters, including both the scattering length a and the effective range r. Our results indicate that a reasonable up-down quark mass difference such as 10 MeV yields a value for |app|-|ann| of about + 0.6 fm, which is sizable from the experimental point of view. Our results also suggest that the large observed value for |anp|-|ann| can be understood primarily as a manifestation of the pion mass difference. [NUCLEAR REACTIONS Application of quark models to nuclear physics; effects of the up-down quark mass difference on couplings of pions to nucleons or isobars; charge dependence and charge symmetry breaking in low energy nucleon-nucleon scattering.]

UR - http://www.scopus.com/inward/record.url?scp=4244012094&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4244012094&partnerID=8YFLogxK

U2 - 10.1103/PhysRevC.29.1

DO - 10.1103/PhysRevC.29.1

M3 - Article

VL - 29

SP - 1

EP - 12

JO - Physical Review C - Nuclear Physics

JF - Physical Review C - Nuclear Physics

SN - 0556-2813

IS - 1

ER -