The Neutron and Its Role in Cosmology and Particle Physics

By D. Dubbers, M. G. Schmidt. 2011

184 citations recorded by the source corpus.

Experiments with cold and ultracold neutrons have reached a level of precision such that problems far beyond the scale of the present standard model of particle physics become accessible to experimental investigation. Because of the close links between particle physics and cosmology, these studies also permit a deep look into the very first instances of our Universe. First addressed in this article, in both theory and experiment, is the problem of baryogenesis, the mechanism behind the evident dominance of matter over antimatter in the Universe. The question of how baryogenesis could have happened is open to experimental tests, and it turns out that this problem can be curbed by the very stringent limits on an electric dipole moment of the neutron, a quantity that also has deep implications for particle physics. Then the recent spectacular observation of neutron quantization in the Earth's gravitational field and of resonance transitions between such gravitational energy states is discussed. These measurements, together with new evaluations of neutron scattering data, set new constraints on deviations from Newton's gravitational law at the picometer scale. Such deviations are predicted in modern theories with extra dimensions that propose unification of the Planck scale with the scale of themore » standard model. These experiments start closing the remaining ''axion window'' on new spin-dependent forces in the submillimeter range. Another main topic is the weak-interaction parameters in various fields of physics and astrophysics that must all be derived from measured neutron-decay data. Up until now, about 10 different neutron-decay observables have been measured, much more than needed in the electroweak standard model. This allows various precise tests for new physics beyond the standard model, competing with or surpassing similar tests at high energy. The review ends with a discussion of neutron and nuclear data required in the synthesis of the elements during the ''first three minutes'' and later on in stellar nucleosynthesis.« less

Subfields: Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/90b19088ed3d3eeb5c48186f13f94c356e6d2c2d

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Atomic and Molecular Physics, and Optics

In Nuclear and High Energy Physics

Citations in the corpus

Electric dipole moments of atoms, molecules, nuclei, and particles (2017, background): “…Lamoreaux (1994), Khriplovich and Lamoreaux (1997), Commins (1999), Sandars (2001), Ginges and Flambaum (2004), Pospelov and Ritz (2005), Commins (2007), Roberts and Marciano (2009), Chupp (2010), Dubbers and Schmidt (2011), Engel et al. (2013), Roberts et al. (2015), and Yamanaka et al. (2017).”
Parton distributions and lattice-QCD calculations: Toward 3D structure (2020, background): “On the other hand, it affects the contribution of quark electric dipole moments to the neutron electric dipole moment in a way which is relevant for searches of bSM sources of CP-violation (Dubbers and Schmidt, 2011; Yamanaka et al., 2017).”
Beta Decays and Non-Standard Interactions in the LHC Era (2013, methodology): “Considerable experimental progress is ongoing or expected in a few-year time scale on several fronts, using both cold and ultracold neutrons [4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20], trapped nuclei [21, 22], and rare pion and kaon decays [23, 24, 25, 26].”
Probing Novel Scalar and Tensor Interactions from (Ultra)Cold Neutrons to the LHC (2011, background): “[4], which, as we will see, is not competitive with other bounds.”