scholarly journals Radiative Decay Widths of Ground and Excited States of Vector Charmonium and Bottomonium

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Hluf Negash ◽  
Shashank Bhatnagar
Keyword(s):  
Mass Spectrum ◽  
Excited States ◽  
Mass Spectra ◽  
Reasonable Agreement ◽  
Radiative Decay ◽  
Decay Constants ◽  
Two Photon ◽  
Quantum Numbers ◽  
Decay Widths ◽  
Input Parameters

We study the radiative decay widths of vector quarkonia for the process of J/ψ(nS)→ηc(nS)γ and Υ(nS)→ηb(nS)γ (for principal quantum numbers n=1,2,3) in the framework of Bethe-Salpeter equation under the covariant instantaneous ansatz using a 4×4 form of BSE. The parameters of the framework were determined by a fit to the mass spectrum of ground states of pseudoscalar and vector quarkonia, such as ηc, ηb, J/ψ, and Υ. These input parameters so fixed were found to give good agreements with data on mass spectra of ground and excited states of pseudoscalar and vector quarkonia, leptonic decay constants of pseudoscalar and vector quarkonia, two-photon decays, and two-gluon decays of pseudoscalar quarkonia in our recent paper. With these input parameters so fixed, the radiative decay widths of ground (1S) and excited (2S,3S) states of heavy vector quarkonia (J/Ψ and Υ) are calculated and found to be in reasonable agreement with data.

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.

ORBITALLY EXCITED STATES OF QUARKONIA IN A NONRELATIVISTIC MODEL

2012 ◽  
Vol 27 (03n04) ◽  
pp. 1250011 ◽  
Author(s):  
BHAGHYESH ◽  
K. B. VIJAYA KUMAR ◽  
YONG-LIANG MA
Keyword(s):  
Wave Function ◽  
Excited States ◽  
Mass Spectra ◽  
Radiative Decay ◽  
Theoretical Models ◽  
Model Parameters ◽  
Linear Potential ◽  
S Wave ◽  
Oscillator Wave Function ◽  
Decay Widths

Having succeeded in predicting the S wave spectra and decays of [Formula: see text] and [Formula: see text] mesons, Bhaghyesh, K. B. Vijaya Kumar and A. P. Monteiro, J. Phys. G: Nucl. Part. Phys.38, 085001 (2011), in this article, we apply our nonrelativistic quark model to calculate the spectra and decays of the orbitally excited states (P- and D-waves) of heavy quarkonia. The full [Formula: see text] potential used in our model consists of a Hulthen potential and a confining linear potential. The spin hyperfine, spin-orbit and tensor interactions are introduced to obtain the masses of the P- and D-wave states. The three-dimensional harmonic oscillator wave function is employed as a trial wave function to obtain the mass spectra. The model parameters and the wave function that reproduce the mass spectra of [Formula: see text] and [Formula: see text] mesons are used to investigate their decay properties. The two-photon decay widths, two-gluon decay widths and E1 radiative decay widths are calculated. The obtained values are compared with the experimental results and those obtained from other theoretical models.

scholarly journals Spectroscopy of ground and excited states of pseudoscalar and vector charmonium and bottomonium

2016 ◽  
Vol 25 (08) ◽  
pp. 1650059 ◽  
Author(s):  
Hluf Negash ◽  
Shashank Bhatnagar
Keyword(s):  
Mass Spectrum ◽  
Excited States ◽  
Weak Decay ◽  
Mass Spectral ◽  
Decay Constants ◽  
Photon Decay ◽  
Oscillator Basis ◽  
Decay Widths ◽  
State Formula ◽  
Spectral Equation

In this paper, we calculate the mass spectrum, weak decay constants, two photon decay widths, and two-gluon decay widths of ground ([Formula: see text]) and radially excited ([Formula: see text]) states of pseudoscalar charmoniuum and bottomonium such as [Formula: see text] and [Formula: see text], as well as the mass spectrum and leptonic decay constants of ground state ([Formula: see text]), excited ([Formula: see text]) states of vector charmonium and bottomonium such as [Formula: see text], and [Formula: see text], using the formulation of Bethe–Salpeter equation under covariant instantaneous ansatz (CIA). Our results are in good agreement with data (where ever available) and other models. In this framework, from the beginning, we employ a [Formula: see text] representation for two-body ([Formula: see text]) BS amplitude for calculating both the mass spectra as well as the transition amplitudes. However, the price we have to pay is to solve a coupled set of equations for both pseudoscalar and vector quarkonia, which we have explicitly shown get decoupled in the heavy-quark approximation, leading to mass spectral equation with analytical solutions for both masses, as well as eigenfunctions for all the above states, in an approximate harmonic oscillator basis. The analytical forms of eigenfunctions for ground and excited states so obtained are used to evaluate the decay constants and decay widths for different processes.

Mechanism for decay and spontaneous radiative decay constants of the lowest‐lying attractive excited states of Ne2, Ar2, and Kr2

1974 ◽  
Vol 61 (11) ◽  
pp. 4740-4746 ◽  
Author(s):  
T. Oka ◽  
K. V. S. Rama Rao ◽  
J. L. Redpath ◽  
R. F. Firestone
Keyword(s):  
Excited States ◽  
Radiative Decay ◽  
Decay Constants

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

2017 ◽  
Vol 32 (04) ◽  
pp. 1750021 ◽  
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.

scholarly journals S-Wave Heavy Quarkonium Spectra: Mass, Decays, and Transitions

2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Halil Mutuk
Keyword(s):  
Logarithmic Potential ◽  
Heavy Quarkonium ◽  
Theoretical Studies ◽  
S Wave ◽  
Potential Models ◽  
Decay Constants ◽  
Two Photon ◽  
Regge Trajectories ◽  
Decay Widths ◽  
Hyperfine Splittings

In this paper we revisited phenomenological potentials. We studied S-wave heavy quarkonium spectra by two potential models. The first one is power potential and the second one is logarithmic potential. We calculated spin averaged masses, hyperfine splittings, Regge trajectories of pseudoscalar and vector mesons, decay constants, leptonic decay widths, two-photon and two-gluon decay widths, and some allowed M1 transitions. We studied ground and 4 radially excited S-wave charmonium and bottomonium states via solving nonrelativistic Schrödinger equation. Although the potentials which were studied in this paper are not directly QCD motivated potential, obtained results agree well with experimental data and other theoretical studies.

scholarly journals Annihilation rates of 3D2(2−−) and 3D3(3−−) heavy quarkonia

2017 ◽  
Vol 32 (06n07) ◽  
pp. 1750035 ◽  
Author(s):  
Tianhong Wang ◽  
Hui-Feng Fu ◽  
Yue Jiang ◽  
Qiang Li ◽  
Guo-Li Wang
Keyword(s):  
Excited States ◽  
Mass Spectra ◽  
Decay Rates ◽  
Wave Functions ◽  
Heavy Quarkonia ◽  
Relativistic Corrections ◽  
Quantum Numbers

We calculate the annihilation decay rates of the [Formula: see text] and [Formula: see text] charmonia and bottomonia by using the instantaneous Bethe–Salpeter (BS) method. The wave functions of states with quantum numbers [Formula: see text] and [Formula: see text] are constructed. By solving the corresponding instantaneous BS equations, we obtain the mass spectra and wave functions of the quarkonia. The annihilation amplitude is written within Mandelstam formalism and the relativistic corrections are taken into account properly. This is important, especially for high excited states, since their relativistic corrections are large. The results for the [Formula: see text] channel are as follows: [Formula: see text] keV, [Formula: see text] keV, [Formula: see text] keV and [Formula: see text] keV.

scholarly journals Charmonium Properties

2020 ◽  
Keyword(s):  
Experimental Data ◽  
Excited States ◽  
Cross Sections ◽  
Mass Spectra ◽  
Potential Model ◽  
Decay Constants ◽  
Theoretical Approaches ◽  
Relativistic Potential ◽  
Data Group ◽  
Good Agreement

We calculated the mass spectra of charmonium meson by using matrix method to make the predictions of ground and radially excited states of charmonium mesons via non-relativistic potential model. We compared our results with other theoretical approaches and recently published experimental data. The predictions are found to be in a good accordance with the latest experimental results of Particle data group and with the results of other theoretical approaches. Besides, we calculated the momentum width coefficients β of charmonium meson. Since, there are no experimental data for the momentum width coefficients β of charmonium meson yet. Consequently, our calculated coefficients β are compared with other theoretical studies and it is found to be in a good agreement with our results. The obtained results of coefficients β have implications for decay constants, decay widths and differential cross sections for charmonium system and generally for heavy mesons system. Our study is considered as theoretical calculation of some properties of charmonium meson.

Restriction of Access to Dark State: A New Mechanistic Model for Heteroatom-Containing AIE Systems

2019 ◽  
Author(s):  
Yujie Tu ◽  
Junkai Liu ◽  
Haoke Zhang ◽  
Qian Peng ◽  
Jacky W. Y. Lam ◽  
...  
Keyword(s):  
Excited States ◽  
Radiative Decay ◽  
Molecular Design ◽  
Mechanistic Model ◽  
Zinc Ion ◽  
Easy Access ◽  
Triplet States ◽  
Dark State ◽  
Ion Probe ◽  
Π State

Aggregation-induced emission (AIE) is an unusual photophysical phenomenon and provides an effective and advantageous strategy for the design of highly emissive materials in versatile applications such as sensing, imaging, and theragnosis. "Restriction of intramolecular motion" is the well-recognized working mechanism of AIE and have guided the molecular design of most AIE materials. However, it sometimes fails to be workable to some heteroatom-containing systems. Herein, in this work, we take more than one excited state into account and specify a mechanism –"restriction of access to dark state (RADS)" – to explain the AIE effect of heteroatom-containing molecules. An anthracene-based zinc ion probe named APA is chosen as the model compound, whose weak fluorescence in solution is ascribed to the easy access from the bright (π,π*) state to the closelying dark (n,π*) state caused by the strong vibronic coupling of the two excited states. By either metal complexation or aggregation, the dark state is less accessible due to the restriction of the molecular motion leading to the dark state and elevation of the dark state energy, thus the emission of the bright state is restored. RADS is found to be powerful in elucidating the photophysics of AIE materials with excited states which favor non-radiative decay, including overlap-forbidden states such as (n,π*) and CT states, spin-forbidden triplet states, which commonly exist in heteroatom-containing molecules.

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