Beyond-the-Quark-Model Heavy Hadrons from QCD Sum Rules
Date
2020-08-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0001-8201-4788
Type
Thesis
Degree Level
Doctoral
Abstract
In this thesis, we examine three papers that my coauthors and I have published. The overarching theme of this work will be the use of QCD Laplace sum rules applied to quarkonium
or quarkonium-like systems containing heavy quarks in an attempt to explore ideas relating
to beyond-the-quark-model hadrons, including hybrids (mesons with gluonic content) and
multi-quark meson-like states.
In the first two papers [1, 2], we study mixing between conventional mesons and hybrids
in vector and axial vector charmonium-like and bottomonium-like systems. We compute
meson-hybrid cross-correlators within the operator product expansion, including condensate
contributions up to dimension-six. We then use the measured masses of heavy quarkoniumlike states as inputs into a QCD Laplace sum-rules calculation to probe known resonances
for nonzero coupling to both the conventional meson and hybrid currents. Nonzero coupling
to both of these currents would signal meson-hybrid mixing. We find nonzero mixing in a
number of resonances over all four of the mass spectra which we probed. The results from
both [1] and [2] are collected and discusses in section 2.7.
In the third paper [3], constituent mass predictions for axial vector cc and bb diquarks
are generated using QCD Laplace sum-rule methods. We calculate the diquark correlator within the operator product expansion to next-to-leading-order, including condensate
contributions up to dimension-six. We find that the constituent mass of the cc diquark is
(3.51 ± 0.35) GeV and the constituent mass of the bb diquark is (8.67 ± 0.69) GeV. We then
use these diquark constituent masses as inputs to calculate several tetraquark masses within
the Type-II chromomagnetic interaction diquark-antidiquark tetraquark model. The results
from the calculations done in [3] are collected in section 3.3.
Description
Keywords
Meson, Hybrid, Mixing, Diquark, Tetraquark, QCD, Sum Rules
Citation
Degree
Doctor of Philosophy (Ph.D.)
Department
Physics and Engineering Physics
Program
Physics