scholarly journals CLASSIFYING REPORTED AND "MISSING" RESONANCES ACCORDING TO THEIR P and C PROPERTIES

2000 ◽  
Vol 15 (10) ◽  
pp. 1435-1451 ◽  
Author(s):  
M. KIRCHBACH
Keyword(s):  
Hilbert Space ◽  
Spin States ◽  
Particle Data Group ◽  
Group Representations ◽  
Opposite Parity ◽  
Quantum Numbers ◽  
Lower Spin ◽  
Missing Resonances ◽  
Lorentz Group Representations ◽  
Data Group

The Hilbert space ℋ3q of the three quarks with one excited quark is decomposed into Lorentz group representations. It is shown that the quantum numbers of the reported and "missing" resonances fall apart and populate distinct representations that differ by their parity or/and charge conjugation properties. In this way, reported and "missing" resonances become distinguishable. For example, resonances from the full listing reported by the Particle Data Group are accommodated by Rarita–Schwinger (RS) type representations [Formula: see text] with k=1, 3, and 5, the highest spin states being J=3/2-, 7/2+, and 11/2+, respectively. In contrast to this, most of the "missing" resonances fall into the opposite parity RS fields of highest-spins 5/2-, 5/2+, and 9/2+, respectively. Rarita–Schwinger fields with physical resonances as lower-spin components can be treated as a whole without imposing auxiliary conditions on them. Such fields do not suffer the Velo–Zwanziger problem but propagate causally in the presence of electromagnetic fields. The pathologies associated with RS fields arise basically because of the attempt to use them to describe isolated spin-J=k+½ states, rather than multispin-parity clusters. The positions of the observed RS clusters and their spacing are well explained trough the interplay between the rotational-like [Formula: see text]-rule and a Balmer-like [Formula: see text]-behavior.

scholarly journals Power Laws and Elementary Particle Decays

Sci ◽  
2019 ◽  
Vol 1 (3) ◽  
pp. 59
Author(s):  
Leonardo Chiatti
Keyword(s):  
Elementary Particle ◽  
Power Law ◽  
Power Laws ◽  
Order Structure ◽  
Particle Data Group ◽  
Rest Energy ◽  
The Standard Model ◽  
Using Data ◽  
Particle Decays ◽  
Data Group

This study analyzes the correlation between the lifetime and the rest energy of the unstable particle states with a lifetime greater than the zeptosecond (10−21 s), using data available from the Particle Data Group. This set of states seems to be divided into three groups, in each of which the two quantities can be correlated through a remarkably accurate power law. Although this fact does not represent anything new compared to the predictions of the Standard Model, it nevertheless reveals an unexpected order structure in the set of particle decays, emerging from such predictions.

scholarly journals KAON PHOTOPRODUCTION ON THE NUCLEON WITH CONSTRAINED PARAMETERS

2009 ◽  
Vol 24 (11n13) ◽  
pp. 964-967
Author(s):  
R. NELSON ◽  
T. MART
Keyword(s):  
Experimental Data ◽  
Particle Data Group ◽  
Resonance Decay ◽  
Decay Widths ◽  
Data Group

The new experimental data of kaon photoproduction on the nucleon γp → K+Λ have been analyzed by means of a multipoles model. Different from the previous models, in this analysis the resonance decay widths are constrained to the values given by the Particle Data Group (PDG). The result indicates that constraining these parameters to the PDG values could dramatically change the conclusion of the important resonances in this reaction found in the previous studies.

scholarly journals Standard versus non-standard CP phases in neutrino oscillation in matter with non-unitarity

2020 ◽  
Vol 2020 (6) ◽  
Author(s):  
Ivan Martinez-Soler ◽  
Hisakazu Minakata
Keyword(s):  
Neutral Current ◽  
Phase Correlation ◽  
Charged Current ◽  
Unitary Matrix ◽  
Particle Data Group ◽  
Unitary Evolution ◽  
First Order ◽  
Flavor Mixing ◽  
Mixing Matrix ◽  
Data Group

Abstract We formulate a perturbative framework for the flavor transformation of the standard active three neutrinos but with a non-unitary flavor mixing matrix, a system which may be relevant for the leptonic unitarity test. We use the $\alpha$ parametrization of the non-unitary matrix and take its elements $\alpha_{\beta \gamma}$ ($\beta,\gamma = e,\mu,\tau$) and the ratio $\epsilon \simeq \Delta m^2_{21} / \Delta m^2_{31}$ as the small expansion parameters. Two qualitatively new features that hold in all the oscillation channels are uncovered in the probability formula obtained to first order in the expansion: (1) The phases of the complex $\alpha$ elements always come into the observable in the particular combination with the $\nu$SM CP phase $\delta$ in the form $[e^{- i \delta } \bar{\alpha}_{\mu e}, ~e^{ - i \delta} \bar{\alpha}_{\tau e}, ~\bar{\alpha}_{\tau \mu}]$ under the Particle Data Group convention of a unitary $\nu$SM mixing matrix. (2) The diagonal $\alpha$ parameters appear in particular combinations $\left( a/b - 1 \right) \alpha_{ee} + \alpha_{\mu \mu}$ and $\alpha_{\mu \mu} - \alpha_{\tau \tau}$, where $a$ and $b$ denote, respectively, the matter potential due to charged current and neutral current reactions. This property holds only in the unitary evolution part of the probability, and there is no such feature in the genuine non-unitary part, while the $\delta$–$\alpha$ parameter phase correlation exists for both. The reason for such remarkable stability of the phase correlation is discussed.

Sign in / Sign up

Export Citation Format

Share Document