Baryon-Meson Couplings in the qq Pair-Creation Quark Model. II: Mesonic Decay Widths of P-Wave Baryons

Experimental measurements of decay branching fractions of semitaunic and semimuonic [Formula: see text] into [Formula: see text] have challenged the lepton flavor universality in standard models with about two standard deviations. In this paper, we first investigate the unitary constraint on form factors of [Formula: see text] meson into [Formula: see text]-wave and [Formula: see text]-wave charmonium. Such constraint leads to the exploration of the [Formula: see text] and other ratios [Formula: see text], [Formula: see text], and [Formula: see text] in a model-independent way. These results together with future experimental measurements can be used to explore the lepton flavor universality in a more systematic way. In addition, we point out that the helicity-dependent ratios [Formula: see text] and [Formula: see text] can also provide complementary information.

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Understanding X(3862), X(3872), and X(3930) spectrum in a Friedrichs-model-like scheme

EPJ Web of Conferences ◽

10.1051/epjconf/201818202129 ◽

2018 ◽

Vol 182 ◽

pp. 02129

Author(s):

Zhiguang Xiao ◽

Zhi-Yong Zhou

Keyword(s):

Quark Model ◽

Good Accuracy ◽

Bound State ◽

P Wave ◽

Hadron Interaction ◽

Friedrichs Model ◽

Charmonium States

In this talk, we review the method we proposed to use the Friedrichs-like model combined with QPC model to include the hadron interaction corrections to the spectrum predicted by the quark model, in particular the Godfrey-Isgur model. This method is then used on the first excited P-wave charmonium states, and X(3862), X(3872), and X(3930) state could be simultaneously produced with a quite good accuracy. The X(3872) state is shown to be a bound state with a large DD* continuum component. At the same time, the hc(2P) state is perdicted at about 3902 MeV with a pole width of about 54 MeV.

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THE CHIRAL QUARK MODEL AND BARYON PHENOMENOLOGY

International Journal of Modern Physics A ◽

10.1142/s0217751x05023335 ◽

2005 ◽

Vol 20 (08n09) ◽

pp. 1785-1790 ◽

Cited By ~ 1

Author(s):

D. O. RISKA

Keyword(s):

Quark Model ◽

Form Factors ◽

Axial Current ◽

Chiral Quark Model ◽

Pion Decay ◽

Decay Widths ◽

Nucleon Form Factors ◽

Baryon Spectra ◽

Baryon Resonances ◽

Covariant Quark Model

The chiral quark model posits that pions couple to the axial current of constituent quarks. This chiral pion coupling governs the pion decays of baryon resonances and also implies pion and multipion interactions between the quarks. The qualitative features of this model for the description of pionic decay widths and baryon spectra are outlined. When the covariant quark model wave function for the nucleon is chosen so as to describe the empirical nucleon form factors the pion decay widths of the positive parity resonances are underpredicted. This indicates the presence of significant multiquark components in these resonances.

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RADIATIVE DECAYS OF BARYONS IN A FIELD THEORETIC QUARK MODEL

International Journal of Modern Physics A ◽

10.1142/s0217751x96002613 ◽

1996 ◽

Vol 11 (32) ◽

pp. 5685-5700 ◽

Cited By ~ 2

Author(s):

A.R. PANDA ◽

R.K. SAHOO

Keyword(s):

Quark Model ◽

Radiative Decay ◽

Constituent Quark ◽

Theoretical Calculations ◽

Wave Functions ◽

Radiative Decays ◽

Quark Field ◽

Decay Widths ◽

Helicity Amplitudes ◽

Decays Of Baryons

Radiative decays of baryons are considered in a field theoretic quark model of composite hadrons where the translationally invariant SU (6) hadron states are described by constituent quark field operators and harmonic oscillator wave functions. The constituent quark field operators of the model satisfying the equal time algebra are also Lorentz-boosted through a spin rotation to describe hadrons in motion. The model, like its earlier success in describing the different hadronic phenomena, in the present investigation without any free parameters, obtains the radiative decay widths and helicity amplitudes in reasonable agreement with other theoretical calculations as well as with the available experimental measurements.

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Mass spectra and decays of ground and orbitally excited cb̄ states in nonrelativistic quark model

International Journal of Modern Physics A ◽

10.1142/s0217751x1750021x ◽

2017 ◽

Vol 32 (04) ◽

pp. 1750021 ◽

Cited By ~ 7

Author(s):

Antony Prakash Monteiro ◽

Manjunath Bhat ◽

K. B. Vijaya Kumar

Keyword(s):

Quark Model ◽

Mass Spectra ◽

Radiative Decay ◽

Weak Decay ◽

Exchange Potential ◽

Complete Spectrum ◽

Confinement Potential ◽

Gluon Exchange ◽

Nonrelativistic Quark Model ◽

Decay Widths

The complete spectrum of [Formula: see text] states is obtained in a phenomenological nonrelativistic quark model (NRQM), which consists of a confinement potential and one gluon exchange potential (OGEP) as effective quark–antiquark potential. We make predictions for the radiative decay (E1 and M1) widths and weak decay widths of [Formula: see text] states in the framework of NRQM formalism.

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NON-LEPTONIC WEAK TRANSITIONS WITH ΔI = 1/2 RULE IN DIQUARK-QUARK MODEL USING THE PAULI-GÜRSEY SYMMETRY

Modern Physics Letters A ◽

10.1142/s0217732394000885 ◽

1994 ◽

Vol 09 (12) ◽

pp. 1059-1069 ◽

Cited By ~ 5

Author(s):

K. SUZUKI ◽

H. TOKI

Keyword(s):

Quark Model ◽

Ground State ◽

Wave Functions ◽

P Wave ◽

Standard Process ◽

Weak Process ◽

Pion Emission ◽

Spin Singlet ◽

Weak Transitions

We study the non-leptonic weak transitions of ground state baryons in diquark-quark model. These weak transitions exhibit the ΔI = 1/2 rule, which is hard to account for in the standard weak process. If the diquark correlations are strong among flavor-antitriplet and spin-singlet pairs, we can make the weak transitions among diquarks followed by pion emission much stronger than the standard process. We estimate all the non-leptonic weak transitions of ground state baryons by assuming the Pauli-Gürsey symmetry together with the SU(6) wave functions. We can account for all the P-wave transition strengths quantitatively and hence the ΔI = 1/2 rule.

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