Joseph Schechter

Bio: Joseph Schechter is an academic researcher from Syracuse University. The author has contributed to research in topics: Meson & Quark. The author has an hindex of 39, co-authored 218 publications receiving 8960 citations. Previous affiliations of Joseph Schechter include University of Southern Denmark & United Arab Emirates University.

Neutrino masses in SU(2) ⊗ U(1) theories

Abstract: We analyze SU(2)\ifmmode\times\else\texttimes\fi{}U(1) theories, denoted by ($n, m$), in which there are $n$ neutrinos belonging to isodoublets and $m$ neutrino isosinglets. The charged-current weak interactions are described by a rectangular matrix $K$ which we explicitly parametrize. The neutral-current neutrino interactions are described by a square matrix $P={K}^{+}K$. This has the consequences that neutrinos may decay into three lighter ones and that neutrino oscillations involving neutral-current interactions should exist. The general formalism for the latter situation is given. Associated material on parametrization of unitary matrices and the quantum theory of Majorana particles is also briefly discussed.

Neutrino decay and spontaneous violation of lepton number

Abstract: The orders of magnitude of decay rates for relatively light neutrinos are studied in the framework of the SU(2)\ifmmode\times\else\texttimes\fi{}U(1) gauge group. The assumption is made that a hierarchy parameter $\ensuremath{\epsilon}(\ensuremath{\approx}(\mathrm{muon}\mathrm{mass})\textdiv{}[\mathrm{some}\mathrm{new}\mathrm{mass}\mathrm{scale}(\mathrm{possibly}\mathrm{much}\mathrm{smaller}\mathrm{than}\mathrm{the}\mathrm{grand}\mathrm{unification}\mathrm{scale})])$ plays a meaningful role in the full theory. For orientation it is first noted that the traditional $\ensuremath{ u}\ensuremath{\gamma}$ decay channel as well as the $3\ensuremath{ u}$ decay channel give neutrino lifetimes which for "typical" parameters are substantially longer than the age of the universe. Then we examine in detail some recent proposals which are claimed to result in greatly speeded-up decays into $\ensuremath{ u}$+Majoron, where the Majoron is a true Goldstone boson associated with spontaneous breakdown of lepton number. In a theory in which the usual Higgs doublet is augmented by a complex singlet (1-2 model) it is noted that the decay width into $\ensuremath{ u}$+Majoron actually vanishes to order ${\ensuremath{\epsilon}}^{5}$. In a theory where the doublet is augmented by a complex triplet (2-3 model) this decay is shown to vanish exactly, neglecting radiative corrections. A more general Majoron theory (1-2-3 model) is constructed and shown to also yield a vanishing tree-level decay rate for $\ensuremath{ u}$+Majoron decay to order ${\ensuremath{\epsilon}}^{5}$. Finally, the tree amplitudes in the 1-2 and 1-2-3 models are shown to give decay widths for $\ensuremath{ u}$+Majoron of order ${\ensuremath{\epsilon}}^{9}$ which correspond to lifetimes much greater than the age of the universe.

Neutrinoless double-β decay in SU(2)×U(1) theories

Abstract: It is shown that gauge theories give contributions to neutrinoless double-$\ensuremath{\beta}$ decay [${(\ensuremath{\beta}\ensuremath{\beta})}_{0\ensuremath{ u}}$] which are not covered by the standard parametrizations. While probably small, their existence raises the question of whether the observation of ${(\ensuremath{\beta}\ensuremath{\beta})}_{0\ensuremath{ u}}$ implies the existence of a Majorana mass term for the neutrino. For a "natural" gauge theory we argue that this is indeed the case.

Is the effective Lagrangian for quantum chromodynamics a σ model

Abstract: A fully interacting effective chiral Lagrangian obeying the anomalous axial-baryon-current conservation law is constructed. This Lagrangian is a generalization of one implied by the $\frac{1}{N}$ approximation. In a certain sense, the old $\ensuremath{\sigma}$ model is recovered. Our Lagrangian displays the dependence of amplitudes on the quantum-chromodynamic vacuum angle $\ensuremath{\theta}$, gives soft ${\ensuremath{\eta}}^{\ensuremath{'}}$ theorems, and hints at a possible complementarity between the instanton and $\frac{1}{N}$ approaches. We can rewrite our model in terms of a gauge-invariant gluon field.

Canonical Neutral Current Predictions From the Weak Electromagnetic Gauge Group SU(3) X $u$(1)

Abstract: A straightforward SU(3) x U(1) model in which there is effectively one new neutral-current parameter (denoted by R) is shown to give the canonical neutrino neutral-current predictions for all values of R. For small R the ''low-energy'' theory is essentially SU(2) x U(1) while for R of the order of one it has a much richer ''low-energy'' gauge-boson mass spectrum. Even in the latter case, the predicted e-d asymmetry agrees with experiment. It is interesting that the atomic-physics parity violation depends sensitively on R.

Quantum Theory of Fields

Abstract: To say that this is the best book on the quantum theory of fields is no praise, since to my knowledge it is the only book on this subject But it is a very good and most useful book The original was written in German and appeared in 1942 This is a translation with some minor changes A few remarks have been added, concerning meson theory and nuclear forces, also footnotes referring to modern work in this field, and finally an appendix on the symmetrization of the energy momentum tensor according to Belinfante Quantum Theory of Fields Prof Gregor Wentzel Translated from the German by Charlotte Houtermans and J M Jauch Pp ix + 224, (New York and London: Interscience Publishers, Inc, 1949) 36s

The ATLAS Experiment at the CERN Large Hadron Collider

Abstract: This paper describes the ATLAS experiment as installed in i ts experimental cavern at point 1 at CERN. It also presents a brief overview of the expec ted performance of the detector.