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The neutron is a subatomic particle, symbol
n
or
n0
, that has no electric charge, and a mass slightly greater than that of a proton. Protons and neutrons constitute the nuclei of atoms. Since protons and neutrons behave similarly within the nucleus, they are both referred to as nucleons. Nucleons have a mass of approximately one atomic mass unit, or dalton. Their properties and interactions are described by nuclear physics. Protons and neutrons are not elementary particles; each is composed of three quarks.
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Anthony Ichiro Sanda is a Japanese-American particle physicist. Along with Ikaros Bigi, he was awarded the 2004 Sakurai Prize for his work on CP violation and B meson decays.
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Standard-Model Extension (SME) is an effective field theory that contains the Standard Model, general relativity, and all possible operators that break Lorentz symmetry. Violations of this fundamental symmetry can be studied within this general framework. CPT violation implies the breaking of Lorentz symmetry, and the SME includes operators that both break and preserve CPT symmetry.
The photon structure function, in quantum field theory, describes the quark content of the photon. While the photon is a massless boson, through certain processes its energy can be converted into the mass of massive fermions. The function is defined by the process e + γ → e + hadrons. It is uniquely characterized by the linear increase in the logarithm of the electronic momentum transfer logQ2 and by the approximately linear rise in x, the fraction of the quark momenta within the photon. These characteristics are borne out by the experimental analyses of the photon structure function.
Helmut Paul was an Austrian nuclear and atomic physicist. He taught as a full professor of experimental physics at the University of Linz from 1971 to 1996. Since then he was professor emeritus. He was Rector of the University from 1974 to 1977.
Asoke Nath Mitra was an Indian theoretical physicist. He was a lifetime professor emeritus at Delhi University. He is known for his work in nuclear physics, particle physics and quantum field theory and in particular, for his fundamental contributions in obtaining the exact solution of the nucleon 3- body problem with separable potentials which led to the few nucleon studies, quark-recoil effect, development of an integrated dynamics of 2- and 3- body systems from nucleons to quarks as well as for the development of quark dynamics and relativistic quark models for hadrons in the Bethe-Salpeter framework. He was awarded the Shanti Swarup Bhatnagar Prize in 1969.
When embedded in an atomic nucleus, neutrons are (usually) stable particles. Outside the nucleus, free neutrons are unstable and have a mean lifetime of 877.75+0.50
−0.44 s or 879.6±0.8 s. Therefore, the half-life for this process is 611±1 s.
The STEREO experiment investigated the possible oscillation of neutrinos from a nuclear reactor into light so-called sterile neutrinos. It was located at the Institut Laue–Langevin (ILL) in Grenoble, France. The experiment took data from November 2016 to November 2020. The final results of the experiment rejected the hypothesis of a light sterile neutrino.
References
- ↑ Dobrozemsky, R.; Kerschbaum, E.; Moraw, G.; Paul, H.; Stratowa, C.; Weinzierl, P. (1975-02-01). "Electron-neutrino angular correlation coefficientameasured from free-neutron decay". Physical Review D. 11 (3). American Physical Society (APS): 510–512. Bibcode:1975PhRvD..11..510D. doi:10.1103/physrevd.11.510. ISSN 0556-2821.
- ↑ Stratowa, Chr.; Dobrozemsky, R.; Weinzierl, P. (1978-12-01). "Ratio derived from the proton spectrum in free-neutron decay". Physical Review D. 18 (11). American Physical Society (APS): 3970–3979. doi:10.1103/physrevd.18.3970. ISSN 0556-2821.
- ↑ Beringer, J.; Arguin, J. -F.; Barnett, R. M.; Copic, K.; Dahl, O.; et al. (Particle Data Group) (2012-07-20). "Review of Particle Physics". Physical Review D. 86 (1). American Physical Society (APS): 0100001. Bibcode:2012PhRvD..86a0001B. doi: 10.1103/physrevd.86.010001 . hdl: 10481/34377 . ISSN 1550-7998.
