A
bstract
Precision measurements in allowed nuclear beta decays and neutron decay are reviewed and analyzed both within the Standard Model and looking for new physics. The analysis incorporates the ...most recent experimental and theoretical developments. The results are interpreted in terms of Wilson coefficients describing the effective interactions between leptons and nucleons (or quarks) that are responsible for beta decay. New global fits are performed incorporating a comprehensive list of precision measurements in neutron decay, superallowed 0
+
→
0
+
transitions, and other nuclear decays that include, for the first time, data from mirror beta transitions. The results confirm the
V
-
A
character of the interaction and translate into updated values for
V
ud
and
g
A
at the 10
−
4
level. We also place new stringent limits on exotic couplings involving left-handed and right-handed neutrinos, which benefit significantly from the inclusion of mirror decays in the analysis.
Precision measurements in nuclear β decay offer a sensitive window to search for new physics beyond the standard electroweak model. Searches for new physics are also a strong motivation for ...experiments carried out at the high energy frontier. It is instructive to confront results from the low energy and the high energy frontiers in order to look for possible complementarities. This paper reviews the constraints on new physics obtained from nuclear and neutron decays and compares them to those from other semi‐leptonic processes and from the LHC. The sensitivity requirements of new precision experiments in β decay, to impact the search for new physics at the light of current and projected LHC results, are updated. Experimental developments in nuclear and neutron β decay are discussed with emphasis on their projected goals to improve the limits on exotic weak couplings.
Precision measurements in nuclear β decay offer a sensitive window to search for new physics beyond the standard electroweak model. Searches for new physics are also a strong motivation for experiments carried out at the high energy frontier. It is instructive to confront results from the low energy and the high energy frontiers in order to look for possible complementarities. This paper reviews the constraints on new physics obtained from nuclear and neutron decays and compares them to those from other semi‐leptonic processes and from the LHC. The sensitivity requirements of new precision experiments in β decay, to impact the search for new physics at the light of current and projected LHC results, are updated. Experimental developments in nuclear and neutron β decay are discussed with emphasis on their projected goals to improve the limits on exotic weak couplings.
The status of tests of the standard electroweak model and of searches for new physics in allowed nuclear β decay and neutron decay is reviewed including both theoretical and experimental ...developments. The sensitivity and complementarity of recent and ongoing experiments are discussed with emphasis on their potential to look for new physics. Measurements are interpreted using a model-independent effective field theory approach enabling to recast the outcome of the analysis in many specific new physics models. Special attention is given to the connection that this approach establishes with high-energy physics. A new global fit of available β-decay data is performed incorporating, for the first time in a consistent way, superallowed 0+→0+ transitions, neutron decay and nuclear decays. The constraints on exotic scalar and tensor couplings involving left- or right-handed neutrinos are determined while a constraint on the pseudoscalar coupling from neutron decay data is obtained for the first time as well. The values of the vector and axial–vector couplings, which are associated within the standard model to Vud and gA respectively, are also updated. The ratio between the axial and vector couplings obtained from the fit under standard model assumptions is CA∕CV=−1.27510(66). The relevance of the various experimental inputs and error sources is critically discussed and the impact of ongoing measurements is studied. The complementarity of the obtained bounds with other low- and high-energy probes is presented including ongoing searches at the Large Hadron Collider.
We report here on the design and development of a new apparatus aiming at a 10-fold improved search for CP-violation in ortho-Positronium decay to be performed at the Facility for Rare Isotope Beams.
The experimental achievements and the current program with the LPCTrap device installed at the LIRAT beam line of the SPIRAL1‐GANIL facility are presented. The device is dedicated to the study of the ...weak interaction at low energy by means of precise measurements of the β−ν angular correlation parameter. Technical aspects as well as the main results are reviewed. The future program with new available beams is briefly discussed.
The experimental achievements and the current program with the LPCTrap device installed at the LIRAT beam line of the SPIRAL1‐GANIL facility are presented. The device is dedicated to the study of the weak interaction at low energy by means of precise measurements of the β−ν angular correlation parameter. Technical aspects as well as the main results are reviewed. The future program with new available beams is briefly discussed.
Precision measurements in nuclear β decay offer a sensitive window to search for new physics beyond the standard electroweak model. Searches for new physics are also a strong motivation for ...experiments carried out at the high energy frontier. It is instructive to confront results from the low energy and the high energy frontiers in order to look for possible complementarities. This paper reviews the constraints on new physics obtained from nuclear and neutron decays and compares them to those from other semi‐leptonic processes and from the LHC. The sensitivity requirements of new precision experiments in β decay, to impact the search for new physics at the light of current and projected LHC results, are updated. Experimental developments in nuclear and neutron β decay are discussed with emphasis on their projected goals to improve the limits on exotic weak couplings.
Superallowed decays within and beyond the standard model Falkowski, Adam; González-Alonso, Martín; Naviliat-Cuncic, Oscar ...
The European physical journal. A, Hadrons and nuclei,
05/2023, Letnik:
59, Številka:
5
Journal Article
Recenzirano
Odprti dostop
This note reviews the role of superallowed transitions in determining the strength of the weak interaction among the lightest quarks and in searching for new physics beyond the standard electroweak ...model. The two sets of superallowed decays in nuclei considered here are pure Fermi and mirror transitions. The first have been scrutinized for more than 50 years. The most relevant results are presented and the role of the nucleus-dependent radiative correction and nucleus-independent inner radiative correction are reviewed. In this context, the systematic study of mirror transitions started about 15 years ago. Despite the significant progress made since then, the data is still limited by experimental uncertainties. Combining the results from all superallowed transitions, which are fully consistent, provides a test of unitarity of the first row of the Cabibbo-Kobayashi-Maskawa matrix, which displays a 2
σ
tension with the standard model.
The experimental achievements and the current program with the LPCTrap device installed at the LIRAT beam line of the SPIRAL1‐GANIL facility are presented. The device is dedicated to the study of the ...weak interaction at low energy by means of precise measurements of the
β−ν
angular correlation parameter. Technical aspects as well as the main results are reviewed. The future program with new available beams is briefly discussed.
Precision measurements in nuclear beta decay provide sensitive means to determine the fundamental coupling of charged fermions to weak bosons and to test discrete symmetries in the weak interaction. ...The main motivation of such measurements is to find deviations from Standard Model predictions as possible indications of new physics. I focus here on two topics related to precision measurements in beta decay, namely: (i) the determination of the
V
ud
element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix from nuclear mirror transitions and (ii) selected measurements of time reversal violating correlations in nuclear and neutron decays. These topics complement those presented in other contributions to this conference.
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