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arXiv · 1910.06111

Spectroscopy and decay properties of bottomonium using instanton induced potential from QCD vacuum

Abstract

Ground state and radial excitation mass spectra of bottomonium states are computed using the Instanton Induced $q \bar{q}$ Potential obtained from Instanton Liquid Model for QCD vacuum. The Schrodinger equation is solved for two body problem using variational method. Hyperfine interactions are incorporated to remove the degeneracy between spin singlet and spin triplet states of $S$ wave masses. Spin-orbit and tensor interactions through one gluon exchange has been added to the spin average masses of P and D wave states. The vector decay constants and pseudoscalar decay constants are also estimated using the Van Royan Weiskopff formula within non-relativistic limit. The di-leptonic, di-gamma, di-gluon decays of the bottomonium states are predicted without and with QCD corrections up to the lowest order using numerical values of the wave function at origin. Tri-gluon decays of respective $S$, $P$ and $D$ states are also studied. Other annihilation decay channels of bottomonium states into $γgg$ , $γγγ$ , $q\bar{q} + g $ are also computed. The radiative transitions of first order like electric dipole transitions (E1) and magnetic dipole transitions (M1) are estimated. Our estimations of the mass spectra and decay properties for bottomonium found to be in excellent agreement with the average experimental values reported by particle data group.

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BibTeXRIS

Bhoomika Pandya, Manan Shah, P C Vinodkumar. 2019-10-14. Spectroscopy and decay properties of bottomonium using instanton induced potential from QCD vacuum. https://arxiv.org/abs/1910.06111

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