Fine structure in the charge ratio of muons at large zenith angles

1968 ◽  
Vol 46 (10) ◽  
pp. S309-S312 ◽  
Author(s):  
G. N. Kelly ◽  
P. K. MacKeown ◽  
S. S. Said ◽  
A. W. Wolfendale
Keyword(s):  
Fine Structure ◽  
Zenith Angle ◽  
Experimental Results ◽  
Charge Ratio

Preliminary experimental results are presented of observations on the charge ratio of muons as a function of energy and of angle at large zenith angles found using the Durham horizontal spectrograph. There is some evidence for a maximum of the charge ratio at about 20 GeV, the magnitude of which increases with increasing zenith angle. Possible explanations of the effect are discussed.

The muon charge ratio at 80° to the zenith

1968 ◽  
Vol 46 (10) ◽  
pp. S313-S317 ◽  
Author(s):  
N. S. Palmer ◽  
W. F. Nash
Keyword(s):  
Energy Range ◽  
Sea Level ◽  
Zenith Angle ◽  
Theoretical Models ◽  
Experimental Results ◽  
Charge Ratio ◽  
Entire Energy Range ◽  
Entire Energy

A brief description is given of a spectrograph recently constructed at Nottingham for the study of muons at large zenith angles. The instrument, situated at a latitude of 50 °N and 30 m above sea level, is at present orientated to accept muons incident in the geomagnetic north–south direction at a mean zenith angle of 80°. Experimental results are presented of the charge ratio among muons in the range of production energies 20–500 GeV. The results, which are found to be consistent with a constant or only slowly varying charge ratio over the entire energy range, are compared with the results of other workers and the predictions of some current theoretical models.

scholarly journals XYZ states at BESIII

2019 ◽  
Vol 212 ◽  
pp. 02003
Author(s):  
Zhentian Sun
Keyword(s):  
Fine Structure ◽  
Partial Wave ◽  
Decay Mode ◽  
Cross Sections ◽  
Precise Measurement ◽  
Partial Wave Analysis ◽  
Experimental Results ◽  
Wave Analysis ◽  
Decay Modes

In this proceeding, I report the most recent experimental results from BESIII about the XYZ sates. Two new X(3872) decay modes are observed, which is X(3872) → ωJ/ψ and X(3872) → π0χc1(1P). Precise measurement of cross sections of various channels reveal more fine structure about Y states. To study the property of Zc states, the Jp of Zc(3900) is determined with partial wave analysis, and a hint of new decay mode of Zc±(3900) → ρ±ηc are observed.

Large-scale CIV3 calculations of fine-structure energy levels and radiative rates in Al-like copper

2009 ◽  
Vol 87 (8) ◽  
pp. 895-907 ◽  
Author(s):  
G. P. Gupta ◽  
A. Z. Msezane
Keyword(s):  
Fine Structure ◽  
Configuration Interaction ◽  
Large Scale ◽  
Radiative Decay ◽  
Energy Levels ◽  
Decay Rates ◽  
Experimental Results ◽  
Oscillator Strengths ◽  
Correct Identification ◽  
Excitation Energies

We have performed large-scale CIV3 calculations of excitation energies from the ground state for 97 fine-structure levels as well as of oscillator strengths and radiative decay rates for all electric-dipole-allowed and intercombination transitions among the fine-structure levels of the terms belonging to the (1s22s22p6)3s23p, 3s3p2, 3s23d, 3p3, 3s3p3d, 3p23d, 3s3d2, 3s24s, 3s24p, 3s24d, 3s24f, and 3s3p4s configurations of Cu XVII. These states are represented by very extensive configuration-interaction (CI) wave functions obtained with the CIV3 (Configuration-Interaction Version 3) computer code of Hibbert. The important relativistic effects in intermediate coupling are incorporated by means of the Breit–Pauli Hamiltonian, which consists of the nonrelativistic term plus the one-body mass correction, Darwin term, and spin–orbit, spin–other-orbit, and spin–spin operators. To keep our calculated energy splittings as close as possible to the experimental values (wherever available), we have made small adjustments to the diagonal elements of the Hamiltonian matrices. Our calculated excitation energies, including their ordering, are in excellent agreement with the available experimental results. From our radiative decay rates we have also calculated radiative lifetimes of some fine-structure levels. The mixing among several fine-structure levels is found to be so strong that the correct identification of these levels becomes very difficult. We believe that our extensive calculations will be useful to experimentalists in identifying the fine-structure levels in their future work. In this calculation we also predict new data for several fine-structure levels where no other theoretical and (or) experimental results are available.

The muon density spectrum at large zenith angles

1968 ◽  
Vol 46 (10) ◽  
pp. S273-S277
Author(s):  
D. Alexander ◽  
B. Holyoak ◽  
M. G. Thompson ◽  
M. J. L. Turner
Keyword(s):  
Transverse Momentum ◽  
Zenith Angle ◽  
High Energy ◽  
Experimental Results ◽  
Density Spectrum ◽  
A Value

The frequency of coincident penetrating particles crossing an area 30 m2 at large zenith angles has been measured, and comparison is made with the results of calculations based upon a model of propagation of the EAS through the atmosphere. The experimental results regarding the rate of recording showers as a function of zenith angle do not agree with a mean transverse momentum of secondaries, in high-energy interactions, of 400 MeV/c, but indicate a value of 800 MeV/c. The variation of rate with zenith angle follows a [Formula: see text] law at large zenith angles. The density spectrum of the showers at large zenith angles has also been measured, and for the larger recorded densities this result is in better agreement with the theory incorporating a mean transverse momentum of 400 MeV/c than that incorporating a value of 800 MeV/c.

Charge ratio of energetic cosmic-ray muons as a function of zenith angle

1974 ◽  
Vol 22 (2) ◽  
pp. 251-262 ◽  
Author(s):  
L. K. Ng ◽  
A. W. Wolfendale
Keyword(s):  
Zenith Angle ◽  
Cosmic Ray ◽  
Charge Ratio

Muon spectra and charge ratio at sea-level at a zenith angle of 45°

1967 ◽  
Vol 51 (2) ◽  
pp. 329-340 ◽  
Author(s):  
O. C. Allkofer ◽  
R. D. Andresen
Keyword(s):  
Sea Level ◽  
Zenith Angle ◽  
Charge Ratio

scholarly journals Fine structure of helium and light helium-like ionsThis paper was presented at the International Conference on Precision Physics of Simple Atomic Systems, held at École de Physique, les Houches, France, 30 May – 4 June, 2010.

2011 ◽  
Vol 89 (1) ◽  
pp. 95-101 ◽  
Author(s):  
Krzysztof Pachucki ◽  
Vladimir A. Yerokhin
Keyword(s):  
Experimental Data ◽  
Fine Structure ◽  
Nuclear Charge ◽  
Structure Constant ◽  
Experimental Results ◽  
Fine Structure Constant ◽  
Atomic Systems ◽  
Fine Structure Splitting ◽  
Theoretical Predictions ◽  
Structure Splitting

Calculational results are presented for the fine structure splitting of the 23P state of helium and helium-like ions with nuclear charge Z up to 10. Theoretical predictions are in agreement with the latest experimental results for the helium fine structure intervals as well as with the most of the experimental data available for light helium-like ions. Comparing the theoretical value of the 23P0-23P1 interval in helium with experimental results (Zelevinsky et al. Phys. Rev. Lett. 95, 203001 (2005)), we determine the value of the fine structure constant α with an accuracy of 31 ppb.

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