Broken chiral symmetry and the classification of B mesons

1984 ◽  
Vol 62 (5) ◽  
pp. 520-526 ◽  
Author(s):  
M. Hatzis
Keyword(s):  
Mass Spectrum ◽  
Chiral Symmetry ◽  
B Mesons ◽  
Axial Current ◽  
Pseudoscalar Mesons ◽  
The Masses

We consider broken SU(5) × SU(5) chiral symmetry and we assume that the vacuum is SU(5)-symmetric. Using the observed mass spectrum of pseudoscalar mesons, and setting the [Formula: see text] mass in the range 5.2 ± 0.06 GeV, we predict the masses of [Formula: see text], [Formula: see text], and ηb states as well as axial current couplings fi/fπ. SU(5) × SU(5) is found to be consistent with SU(4) × SU(4) breaking. The problem of η − η′ − ηe − ηb mixing is also discussed.

Remarks on broken chiral SU(5) × SU(5) symmetry and B mesons

1985 ◽  
Vol 63 (10) ◽  
pp. 1294-1298
Author(s):  
D. Y. Kim ◽  
S. N. Sinha
Keyword(s):  
B Mesons ◽  
Decay Constant ◽  
B Meson ◽  
Weak Decay ◽  
Sum Rule ◽  
Decay Constants ◽  
Symmetry Approach ◽  
Rule Model ◽  
Pseudoscalar Mesons ◽  
The Masses

In a recent paper, Hatzis has estimated the masses and weak decay constants of b-flavored pseudoscalar mesons in a broken chiral SU(5) × SU(5) symmetry method. The estimated weak decay constant of B meson, [Formula: see text], however, does not agree with the value [Formula: see text] evaluated by Mathur et al. with the quantum chromodynamics (QCD) sum-rule model. We re-examined the problem applying the broken chiral SU(5) × SU(5) symmetry approach using a set of mass formulae. With this method we estimate the symmetry-breaking parameters and decay constants of pseudoscalar mesons. We found a consistent result for the decay constant: [Formula: see text]. The explicit numerical value of these constants, however, are lower than that of the QCD sum rule. This may be due to the limited validity of the broken chiral symmetry approach for heavy mesons.

scholarly journals KDClassifier: Urinary Proteomic Spectra Analysis Based on Machine Learning for Classification of Kidney Diseases

2020 ◽  
Author(s):  
Wanjun Zhao ◽  
Yong Zhang ◽  
Xinming Li ◽  
Yonghong Mao ◽  
Changwei Wu ◽  
...  
Keyword(s):  
Machine Learning ◽  
Mass Spectrum ◽  
Kidney Disease ◽  
Kidney Diseases ◽  
Training Dataset ◽  
Validation Dataset ◽  
Support Vector ◽  
Urinary Proteomics ◽  
Diagnosis Model

AbstractBackgroundBy extracting the spectrum features from urinary proteomics based on an advanced mass spectrometer and machine learning algorithms, more accurate reporting results can be achieved for disease classification. We attempted to establish a novel diagnosis model of kidney diseases by combining machine learning with an extreme gradient boosting (XGBoost) algorithm with complete mass spectrum information from the urinary proteomics.MethodsWe enrolled 134 patients (including those with IgA nephropathy, membranous nephropathy, and diabetic kidney disease) and 68 healthy participants as a control, and for training and validation of the diagnostic model, applied a total of 610,102 mass spectra from their urinary proteomics produced using high-resolution mass spectrometry. We divided the mass spectrum data into a training dataset (80%) and a validation dataset (20%). The training dataset was directly used to create a diagnosis model using XGBoost, random forest (RF), a support vector machine (SVM), and artificial neural networks (ANNs). The diagnostic accuracy was evaluated using a confusion matrix. We also constructed the receiver operating-characteristic, Lorenz, and gain curves to evaluate the diagnosis model.ResultsCompared with RF, the SVM, and ANNs, the modified XGBoost model, called a Kidney Disease Classifier (KDClassifier), showed the best performance. The accuracy of the diagnostic XGBoost model was 96.03% (CI = 95.17%-96.77%; Kapa = 0.943; McNemar’s Test, P value = 0.00027). The area under the curve of the XGBoost model was 0.952 (CI = 0.9307-0.9733). The Kolmogorov-Smirnov (KS) value of the Lorenz curve was 0.8514. The Lorenz and gain curves showed the strong robustness of the developed model.ConclusionsThis study presents the first XGBoost diagnosis model, i.e., the KDClassifier, combined with complete mass spectrum information from the urinary proteomics for distinguishing different kidney diseases. KDClassifier achieves a high accuracy and robustness, providing a potential tool for the classification of all types of kidney diseases.

PROCEDURE FOR GENERATING EQUATIONS IN LINEAR SIGMA MODEL

2011 ◽  
Vol 26 (14) ◽  
pp. 2327-2352 ◽  
Author(s):  
AMIR H. FARIBORZ
Keyword(s):  
Scattering Amplitudes ◽  
Sigma Model ◽  
Point Interaction ◽  
Low Energy ◽  
Linear Sigma Model ◽  
Pseudoscalar Mesons ◽  
Decay Widths ◽  
Symmetry Breaking Term ◽  
The Masses ◽  
Breaking Term

A procedure for implementation of the generating equations in the linear sigma model of low energy QCD is presented. For any explicit symmetry breaking term, this procedure computes the masses of scalar and pseudoscalar mesons as well as various three-point and four-point interaction vertices that are needed in calculation of different decay widths and scattering amplitudes.

Mass spectrum and leptonic decay constants of ground and radially excited states of ηc and ηb in a Bethe–Salpeter equation framework

2015 ◽  
Vol 24 (04) ◽  
pp. 1550030 ◽  
Author(s):  
Hluf Negash ◽  
Shashank Bhatnagar
Keyword(s):  
Mass Spectrum ◽  
Excited States ◽  
Ground State ◽  
Reasonable Agreement ◽  
Equal Mass ◽  
Leptonic Decay ◽  
Decay Constants ◽  
Pseudoscalar Mesons

In this paper, we study the mass spectrum and decay constants of ground state (1S) and radially excited states (2S and 3S) of heavy equal mass pseudoscalar mesons, ηc and ηb. We have employed the framework of Bethe–Salpeter equation (BSE) under Covariant Instantaneous Ansatz (CIA). Our predictions are in reasonable agreement with the data on available states and results of other models.

Breaking of Chiral Symmetry for Pseudoscalar Mesons

1969 ◽  
Vol 183 (5) ◽  
pp. 1463-1468 ◽  
Author(s):  
P. R. Auvil ◽  
N. G. Deshpande
Keyword(s):  
Chiral Symmetry ◽  
Pseudoscalar Mesons

SUBSTRUCTURE EFFECTS AT LEP100

1991 ◽  
Vol 06 (01) ◽  
pp. 1-19 ◽  
Author(s):  
F. BOUDJEMA
Keyword(s):  
Chiral Symmetry ◽  
Composite Structure ◽  
Phenomenological Approach ◽  
Novel Interactions ◽  
Guiding Principles ◽  
The Masses ◽  
New Particles

I briefly review the searches being performed at LEP100 for new particles and novel interactions in the context of a composite structure. While the emphasis is on the most promising signals, the presentation follows a very broad phenomenological approach rather than listing predictions from specific models of substructure although some general guiding principles (such as chiral symmetry and global SU(2) weak invariance) have been incorporated in the analysis. Preliminary limits on the masses of certain particles are set from the autumn 1989 run.

scholarly journals NEW ANGLE ON THE STRONG CP AND CHIRAL SYMMETRY PROBLEMS FROM A ROTATING MASS MATRIX

2009 ◽  
Vol 24 (01) ◽  
pp. 101-112 ◽  
Author(s):  
JOSÉ BORDES ◽  
HONG-MO CHAN ◽  
TSOU SHEUNG TSUN
Keyword(s):  
Chiral Symmetry ◽  
Chiral Symmetry Breaking ◽  
Mass Matrix ◽  
Energy Scale ◽  
Fermion Mass ◽  
Mass Hierarchy ◽  
Quark Masses ◽  
Chiral Transformation ◽  
The Masses ◽  
Fermion Mass Matrix

It is shown that when the mass matrix changes in orientation (i.e. rotates) in generation space for a changing energy scale, the masses of the lower generations are not given just by its eigenvalues. In particular, these masses need not be zero even when the eigenvalues are zero. In that case, the strong CP problem can be avoided by removing the unwanted θ term by a chiral transformation not in contradiction with the nonvanishing quark masses experimentally observed. Similarly, a rotating mass matrix may shed new light on the problem of chiral symmetry breaking. That the fermion mass matrix may so rotate with the scale has been suggested before as a possible explanation for up–down fermion mixing and fermion mass hierarchy, giving results in good agreement with experiment.

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