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Related papers: Neutron beta-decay, Standard Model and cosmology

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The impact of new and highly precise neutron \b{eta} decay data is reviewed. We focus on recent results from neutron lifetime, \b{eta} asymmetry, and electron-neutrino correlation experiments. From these results, weak interaction parameters…

Nuclear Experiment · Physics 2021-06-07 Dirk Dubbers , Bastian Märkisch

The existing discrepancy between neutron lifetime measurements in bottle and beam experiments has been interpreted as a sign of the neutron decaying to dark particles. We summarize the current status of this proposal, including a discussion…

High Energy Physics - Phenomenology · Physics 2020-10-13 Bartosz Fornal , Benjamin Grinstein

The author considers a hypothesis of neutron lifetime splitting in beta-decay and shows that the beta-decay of neutrons could be described by the triad of lifetimes tau_{Left}, tau_{Mean}, tau_{Right}. The lifetime tau_{Left} is the…

Data Analysis, Statistics and Probability · Physics 2019-04-01 V. V. Vasiliev

The most precise determination of the neutron lifetime using the beam method was completed in 2005 and reported a result of $\tau_n = (886.3 \pm 1.2 [\textrm{stat}] \pm 3.2 [\textrm{syst}])$ s. The dominant uncertainties were attributed to…

Nuclear Experiment · Physics 2013-11-28 A. T. Yue , M. S. Dewey , D. M. Gilliam , G. L. Greene , A. B. Laptev , J. S. Nico , W. M. Snow , F. E. Wietfeldt

Future cosmological data may be sensitive to the effects of a finite sum of neutrino masses even as small as ~0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a cosmological detection of neutrino mass at…

Astrophysics · Physics 2008-11-26 Pasquale D. Serpico

The discrepancy between the neutron lifetimes measured in the beam and trap experiments can be explained via the neutron $n$ conversion into mirror neutron $n'$, its dark partner from parallel mirror sector, provided that $n$ and $n'$ have…

High Energy Physics - Phenomenology · Physics 2019-06-26 Zurab Berezhiani

We use data from the Lunar Prospector Neutron Spectrometer to make the second space-based measurement of the free neutron lifetime finding $\tau_n=887 \pm 14_\text{stat}{\:^{+7}_{-3\:\text{syst}}}$ s, which is within 1$\sigma$ of the…

In a variety of neutron lifetime experiments, in addition to $\beta-$decay, neutrons can be lost by other mechanisms including wall losses. Failure to account for these other loss mechanisms produces systematic measurement error and…

The neutron lifetime is one of the basic parameters in the weak interaction, and is used for predicting the light element abundance in the early universe. Our group developed a new setup to measure the lifetime with the goal precision of…

We report a new measurement of the neutron decay lifetime by the absolute counting of in-beam neutrons and their decay protons. Protons were confined in a quasi-Penning trap and counted with a silicon detector. The neutron beam fluence was…

We review the status of the Standard Model theory of neutron beta decay. Particular emphasis is put on the recent developments in the electroweak radiative corrections. Given that some existing approaches give slightly different results, we…

High Energy Physics - Phenomenology · Physics 2023-11-01 Mikhail Gorchtein , Chien-Yeah Seng

The manuscript by Berezhiani (arXiv:1812.11089) proposes a model that has the neutron decaying into a mirror neutron with a branching fraction of 1%, alleviating the tension between neutron lifetime measurements in beam vs bottle…

High Energy Physics - Phenomenology · Physics 2019-02-26 Bartosz Fornal , Benjamin Grinstein

There exists a puzzling disagreement between the results for the neutron lifetime obtained in experiments using the beam technique versus those relying on the bottle method. A possible explanation of this discrepancy postulates the…

High Energy Physics - Phenomenology · Physics 2023-10-18 Bartosz Fornal

Since long neutron lifetimes measured with a beam of cold neutrons are significantly different from lifetimes measured with ultracold neutrons bottled in a trap. It is often speculated that this "neutron anomaly" is due to an exotic dark…

Nuclear Experiment · Physics 2019-02-20 D. Dubbers , H. Saul , B. Märkisch , T. Soldner , H. Abele

The experimental determination of V_{ud} from neutron beta decay requires accurate values of the neutron lifetime and the ratio of the weak axial-vector to vector coupling constants of the nucleon. The latter is derived from measurements of…

Nuclear Experiment · Physics 2013-02-19 Oliver Zimmer

Quantum mechanics predicts that the decay rate of unstable systems could be effectively modified by the process of the measurement of the survival probability. Depending on the intrinsic properties of the unstable system and the…

High Energy Physics - Phenomenology · Physics 2020-03-11 Francesco Giacosa , Giuseppe Pagliara

We revisit the neutron lifetime puzzle, a discrepancy between beam and bottle measurements of the weak neutron decay. Since both types of measurements are realized at different times after the nuclear production of free neutrons, we argue…

High Energy Physics - Phenomenology · Physics 2024-09-23 Benjamin Koch , Felix Hummel

Constraints on the lifetime of the heavy sterile neutrino, that was proposed as a possible interpretation of the KARMEN anomaly, are derived from primordial nucleosynthesis and SN 1987A. Together with the recent experimental bounds on the…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. D. Dolgov , S. H. Hansen , G. Raffelt , D. V. Semikoz

There is a long-standing discrepancy between the neutron lifetime measured in beam and bottle experiments. We propose to explain this anomaly by a dark decay channel for the neutron, involving one or more dark sector particles in the final…

High Energy Physics - Phenomenology · Physics 2018-05-10 Bartosz Fornal , Benjamin Grinstein

The ``neutron lifetime puzzle'' arises from the discrepancy between neutron lifetime measurements obtained using the beam method, which measures decay products, and the bottle method, which measures the disappearance of neutrons. To resolve…