NONRELATIVISTIC QUARK–ANTIQUARK POTENTIAL: SPECTROSCOPY OF HEAVY-QUARKONIA AND EXOTIC SUSY QUARKONIA

The experiments at LHC have shown that the SUSY (exotic) bound states are likely to form bound states in an entirely similar fashion as ordinary quarks form bound states, i.e. quarkonium. Also, the interaction between two squarks is due to gluon exchange which is found to be very similar to that interaction between two ordinary quarks. This motivates us to solve the Schrödinger equation with a strictly phenomenological static quark–antiquark potential: [Formula: see text] using the shifted large N-expansion method to calculate the low-lying spectrum of a heavy quark with antisbottom [Formula: see text] and sbottom with antisbottom [Formula: see text] bound states with [Formula: see text] is set free. To have a full knowledge on spectrum, we also give the result for a heavier as well as for lighter sbottom masses. As a test for the reliability of these calculations, we fix the parameters of this potential by fitting the spin-triplet (n3S1) and center-of-gravity l≠0 experimental spectrum of the ordinary heavy quarkonia [Formula: see text], [Formula: see text] and [Formula: see text] to few MeV. Our results are compared with other models to gauge the reliability of these predictions and point out differences.

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SPECTROSCOPY OF Bc MESON IN A SEMI-RELATIVISTIC QUARK MODEL USING THE SHIFTED LARGE-N EXPANSION METHOD

International Journal of Modern Physics A ◽

10.1142/s0217751x0401780x ◽

2004 ◽

Vol 19 (11) ◽

pp. 1771-1791 ◽

Cited By ~ 51

Author(s):

SAMEER M. IKHDAIR ◽

RAMAZAN SEVER

Keyword(s):

Bound States ◽

Expansion Method ◽

The Other ◽

Minimal Subtraction ◽

Third Order ◽

Large N ◽

Expansion Technique ◽

Energy Bound ◽

Bc Meson ◽

Large N Expansion

We calculate the [Formula: see text] mass spectrum, the splitting values and some other properties in the framework of the semirelativistic equation by applying the shifted large-N expansion technique. We use seven different central potentials together with an improved QCD-motivated interquark potentials calculated to two loops in the modified minimal-subtraction [Formula: see text] scheme. The parameters of these potentials are fitted to generate the semirelativistic bound states of [Formula: see text] quarkonium system in close conformity with the experimental and the present available calculated center-of-gravity (c.o.g.) data. Calculations of the energy bound states are carried out up to third order. Our results are in excellent fit with the results of the other works.

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Spin-dependent fragmentation functions of gluon splitting into heavy quarkonia considering three different scenarios

International Journal of Modern Physics A ◽

10.1142/s0217751x15501791 ◽

2015 ◽

Vol 30 (32) ◽

pp. 1550179 ◽

Cited By ~ 12

Author(s):

S. Mohammad Moosavi Nejad ◽

Mahdi Delpasand

Keyword(s):

Heavy Quark ◽

Bound State ◽

Heavy Quarkonia ◽

Heavy Quarkonium ◽

Heavy Quark Mass ◽

Spin Singlet ◽

Fragmentation Probability ◽

Spin Triplet ◽

Fragmentation Functions ◽

Heavy Quark Pair

Heavy quarkonium production is a powerful implement to study the strong interaction dynamics and QCD theory. Fragmentation is the dominant production mechanism for heavy quarkonia with large transverse momentum. With the large heavy quark mass, the relative motion of the heavy quark pair inside a heavy quarkonium is effectively nonrelativistic and it is also well known that their fragmentation functions can be calculated in the perturbative QCD framework. Here, we analytically calculate the process-independent fragmentation functions for a gluon to split into the spin-singlet and spin-triplet [Formula: see text]-wave heavy quarkonia using three different scenarios. We will show that the fragmentation probability of the gluon into the spin-triplet bound-state is the biggest one.

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A SYSTEMATIC STUDY ON NONRELATIVISTIC QUARKONIUM INTERACTION

International Journal of Modern Physics A ◽

10.1142/s0217751x06030953 ◽

2006 ◽

Vol 21 (19n20) ◽

pp. 3989-4002 ◽

Cited By ~ 26

Author(s):

SAMEER M. IKHDAIR ◽

RAMAZAN SEVER

Keyword(s):

Systematic Study ◽

Mass Spectra ◽

Potential Model ◽

Expansion Method ◽

Leptonic Decay ◽

Large N ◽

Decay Widths ◽

Hyperfine Splittings ◽

The Masses ◽

Static Quark

A recently proposed strictly phenomenological static quark–antiquark potential belonging to the generality V(r) = -Ar-α + κrβ + V0 is tested with heavy quarkonia in the context of the shifted large N-expansion method. This nonrelativistic potential model fits the spin-averaged mass spectra of the [Formula: see text], [Formula: see text] and [Formula: see text] quarkonia within a few MeV and also the five experimentally known leptonic decay widths of the [Formula: see text] and [Formula: see text] vector states. Further, we compute the hyperfine splittings of the bottomonium spectrum as well as the fine and hyperfine splittings of the charmonium spectrum. We give predictions for not yet observed Bc splittings. The model is then used to predict the masses of the remaining quarkonia and the leptonic decay widths of the two pseudoscalar [Formula: see text] states. Our results are compared with other models to gauge the reliability of the predictions and point out differences.

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The Genuine Resonance of Full-Charm Tetraquarks

Universe ◽

10.3390/universe7050155 ◽

2021 ◽

Vol 7 (5) ◽

pp. 155

Author(s):

Xiaoyun Chen

Keyword(s):

Quark Model ◽

Bound States ◽

Expansion Method ◽

Chiral Quark Model ◽

Stabilization Method ◽

Scaling Method ◽

Resonance States ◽

Gaussian Expansion Method ◽

Color Structure ◽

Quantum Numbers

In this work, the genuine resonance states of full-charm tetraquark systems with quantum numbers JPC=0++,1+−,2++ are searched in a nonrelativistic chiral quark model with the help of the Gaussian Expansion Method. In this calculation, two structures, meson-meson and diquark–antidiquark, as well as their mixing with all possible color-spin configurations, are considered. The results show that no bound states can be formed. However, resonances are possible because of the color structure. The genuine resonances are identified by the stabilization method (real scaling method). Several resonances for the full-charm system are proposed, and some of them are reasonable candidates for the full-charm states recently reported by LHCb.

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