Isospin Symmetry Breaking in the Quark Condensates, $< \bar dd>\not= < \bar uu>$, as Estimated from QCD Sum Rules
| dc.creator | Hwang, W-Y. P. | |
| dc.creator | Yang, Kwei-Chou | |
| dc.date | 1998-03-21 | |
| dc.date.accessioned | 2026-07-07T04:03:38Z | |
| dc.date.available | 2026-07-07T04:03:38Z | |
| dc.description | Isospin symmetry breaking in the quark condensates, $< \bar dd> \not= < \bar uu>$, is a fundamental parameter in both the QCD sum rule studies and the chiral perturbation theory. In this article, we apply the QCD sum rule method to treat the hyperon mass difference ${1\over 2}(m_{Σ^-}+m_{Σ^0})-m_{Σ^+}$ in order to obtain a reasonable estimate on such isospin symmetry breaking parameter $γ$ defined as $(< \bar dd>-< \bar uu>)/ < \bar uu>$. Note that the electromagnetic contributions to the particular mass difference are expected to cancel almost completely. Using the light-quark mass difference $m_d-m_u=4\pm 1$ MeV and the experimental data ${1\over 2}(m_{Σ^-}+m_{Σ^0})-m_{Σ^+}$$=5.62\pm 0.13$ MeV, we obtain $γ= -0.011\pm 0.001$, a value which is slightly larger than the commonly adopted value and is of smaller uncertainty. | |
| dc.description | 10 pages, 2 figures, Latex | |
| dc.identifier | https://arxiv.org/abs/hep-ph/9803413 | |
| dc.identifier | http://arxiv.org/abs/hep-ph/9803413 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/47741 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Isospin Symmetry Breaking in the Quark Condensates, $< \bar dd>\not= < \bar uu>$, as Estimated from QCD Sum Rules | |
| dc.type | text |