From three physical-point twisted mass ensembles, the authors extract g_A, the axial radius, g_P^* and g_piNN in the continuum limit and report that PCAC and pion pole dominance hold.
Determination of the Weak Axial Vector Coupling from a Measurement of the Beta-Asymmetry Parameter A in Neutron Beta Decay
1 Pith paper cite this work. Polarity classification is still indexing.
1
Pith paper citing it
abstract
We report on a new measurement of the neutron beta-asymmetry parameter $A$ with the instrument \perkeo. Main advancements are the high neutron polarization of $P = 99.7(1)%$ from a novel arrangement of super mirror polarizers and reduced background from improvements in beam line and shielding. Leading corrections were thus reduced by a factor of 4, pushing them below the level of statistical error and resulting in a significant reduction of systematic uncertainty compared to our previous experiments. From the result $A_0 = -0.11996(58)$, we derive the ratio of the axial-vector to the vector coupling constant $\lambda = g_\mathrm{A}/g_\mathrm{V} = -1.2767(16)$
fields
hep-lat 1years
2025 1verdicts
CONDITIONAL 1representative citing papers
citing papers explorer
-
Isovector axial and pseudoscalar form factors from twisted mass lattice QCD at the physical point
From three physical-point twisted mass ensembles, the authors extract g_A, the axial radius, g_P^* and g_piNN in the continuum limit and report that PCAC and pion pole dominance hold.