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Related papers: On the neutron lifetime anomaly

200 papers

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

We calculate the rate of neutron-mirror-neutron oscillations for ultracold neutrons trapped in a storage vessel. Recent experimental bounds on the oscillation time are discussed.

High Energy Physics - Phenomenology · Physics 2009-11-13 B. Kerbikov , O. Lychkovskiy

We have measured the trapping lifetime of magnetically trapped atoms in a cryogenic atom-chip experiment. An ultracold atomic cloud is kept at a fixed distance from a thin gold layer deposited on top of a superconducting trapping wire. The…

The analysis of the data on measurements of the neutron lifetime is presented. A new most accurate result of the measurement of neutron lifetime [Phys. Lett. B 605 (2005) 72] 878.5 +/- 0.8 s differs from the world average value [Phys. Lett.…

Nuclear Experiment · Physics 2014-11-21 A. P. Serebrov , A. K. Fomin

Precision measurements of the free neutron lifetime $\tau_n$, when combined with measurements of the axial vector form factor, can be used to test unitarity of the CKM matrix. Non-unitarity is a signal for physics Beyond the Standard Model…

Nuclear Experiment · Physics 2018-10-03 Nathan Callahan

It was recently suggested that the discrepancy between two methods of measuring the lifetime of the neutron may be a result of an unseen decay mode into a dark matter particle which is almost degenerate with the neutron. We explore the…

Nuclear Theory · Physics 2018-05-09 T. F. Motta , P. A. M. Guichon , A. W. Thomas

Neutron lifetime is a critical parameter in the Standard Model. Its measurements using, particularly, the beamline and ultracold neutron storage techniques reveals serious tension. The status of the tension between various measurements have…

Nuclear Experiment · Physics 2024-01-22 Prajwal Mohanmurthy , Joseph Formaggio , Daniel J. Salvat , Jeff A. Winger

The decay of the free neutron into a proton, electron, and antineutrino is the prototype semileptonic weak decay and the simplest example of nuclear beta decay. The nucleon vector and axial vector weak coupling constants G_V and G_A…

Nuclear Experiment · Physics 2014-11-14 F. E. Wietfeldt

We study the lifetime of an atom trapped in an optical vertical lattice in proximity of a massive surface using a complex scaling approach. We analyze how the presence of the surface modifies the known lifetimes of Wannier-Stark states…

Quantum Physics · Physics 2013-10-18 Sophie Pelisson , Riccardo Messina , Marie-Christine Angonin , Peter Wolf

We investigate the possibility to trap ultracold atoms near the outside of a metallic carbon nanotube (CN) which we imagine to use as a miniaturized current-carrying wire. We calculate atomic spin flip lifetimes and compare the strength of…

Quantum Physics · Physics 2009-11-13 Rachele Fermani , Stefan Scheel , Peter L. Knight

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 confinement of ultracold neutrons (UCNs) in a three dimensional magnetic field gradient trap allows for a measurement of the free neutron lifetime with superior control over spurious loss channels and can provide a large kinetic energy…

We present the first measurements of the survival time of ultracold neutrons (UCNs) in solid deuterium SD2. This critical parameter provides a fundamental limitation to the effectiveness of superthermal UCN sources that utilize solid…

The problem of possible application of an ultracold neutron (UCN) trap as a detector of dark matter particles with long-range radius of forces has been considered. Transmission of small recoil energy in scattering is a characteristic of…

Nuclear Experiment · Physics 2013-05-30 A. P. Serebrov , O. M. Zherebtsov , A. K. Fomin , M. S. Onegin

In above mentioned article [1] assumptions of possible systematic errors of our experiment on measuring of the neutron lifetime [2] have been made. In the given comment we are obliged to explain, that assumptions made in [1] are erroneous.…

Nuclear Experiment · Physics 2010-01-20 A. Serebrov , A. Fomin , V. Varlamov

In the UCN{\tau} experiment, ultracold neutrons (UCN) are confined by magnetic fields and the Earth's gravitational field. Field-trapping mitigates the problem of UCN loss on material surfaces, which caused the largest correction in prior…

The article provides a theoretical substantiation for a significant increase in the level of accuracy in determining the neutron lifetime using an alternative concept of neutron beta decay. Neutrons are distributed among different subsets…

Nuclear Theory · Physics 2023-08-03 V. V. Vasiliev

The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. The neutron lifetime recently obtained, 878.5 +/- 0.7stat +/- 0.3sys s, is the most accurate one to date. The new result for the…

Nuclear Experiment · Physics 2008-11-26 A. P. Serebrov

We summarize our recent proposal of explaining the discrepancy between the bottle and beam measurements of the neutron lifetime through the existence of a dark sector, which the neutron can decay to with a branching fraction 1%. We show…

High Energy Physics - Phenomenology · Physics 2018-11-07 Bartosz Fornal , Benjamin Grinstein

A model of $n-n'$ (neutron-mirror neutron) oscillations is proposed under the framework of the mirror matter theory with slightly broken mirror symmetry. It resolves the neutron lifetime discrepancy, i.e., the 1% difference in neutron…

General Physics · Physics 2020-09-04 Wanpeng Tan