Related papers: Exotic candidates with heavy quark(s)
We investigate the exotic hadrons consisting of two light quarks and two heavy antiquarks, $(q\bar Q)$-$(q\bar Q)$. The spin-dependent term between quarks is known to give an attraction to the $ud$ spin-0 component in the isospin-0 $u\bar c…
We review selected lattice results on the charmonium spectrum and first attempts to search for the existence of exotic states. The hadro-quarkonium model was proposed to interpret some of the exotic states as a quarkonium core inside a…
Beyond black holes and neutron stars, new hypothetical compact objects have been proposed as potential astrophysical entities. In general, their properties have not yet been fully explored or understood, nor has it been proven whether or…
Lattice QCD approach to study the hadronic resonances and exotic hadrons is described at an introductory level. The main challenge is that these states decay strongly via one or more decay channels, and they often lie near thersholds.…
A central question in exotic-hadron physics is their internal structure whether these states are loosely bound hadronic molecules or compact multiquark configurations. To shed light on this issue, we develop a model that incorporates mixing…
How massive the hybrid stars could be is discussed by a "3-window model" proposed from a new strategy to construct the equation of state with hadron-quark transition. It is found that hybrid stars have a strong potentiality to generate a…
Explosive astrophysical systems, such as supernovae or compact star binary mergers, provide conditions where strange quark matter can appear. The high degree of isospin asymmetry and temperatures of several MeV in such systems may cause a…
We study charmonium ($c\bar c n\bar n$), bottomonium ($b\bar b n\bar n$) and exotic ($cc\bar n\bar n$ and $bb\bar n\bar n$) four-quark states by means of a standard non-relativistic quark potential model. We look for possible bound states.…
Highly effective conversion of kinetic energy into abundant particle multiplicity is the remarkable feature discovered in high energy heavy ion collisions. This short and pedagogic review addresses topical issues related to the…
Exotic quarkonia are candidates to new types of hadrons including four quarks or gluonic degrees of freedom as constituents, the latter being a unique feature of QCD. We review recent developments in nonrelativistic EFTs to describe exotic…
Using the Born-Oppenheimer approximation, we show that exotic resonances, X and Z, may emerge as QCD molecular objects made of colored two-quark lumps, states with heavy-light diquarks spatially separated from antidiquarks. With the same…
The past four years has witnessed the renaissance of the hadron spectroscopy. Many interesting new hadron states were discovered experimentally, some of which do not fit into the quark model easily. I will give a concise overview of these…
We present a class of models in which the top quark, by mixing with new physics at a higher energy scale, is naturally heavier than the other standard model particles. We take this new physics to be extended color. Our models contain new…
Multiquark systems such as tetraquarks, pentaquarks and hexaquarks states are studied as di-hadronic molecules in a nonrelativistic model. The masses of several di-hadronic states using a molecular interaction provided by asymptotic…
In the quark model, hadrons are dominantly bound states of quark-antiquark pairs (mesons) or three quarks (baryons), but QCD also allows hadronic states to be composed of more quarks bound together. Recently, BESIII, Belle and LHCb have…
The problems of simple elementary weakly interacting massive particles (WIMPs) appeal to extend the physical basis for nonbaryonic dark matter. Such extension involves more sophisticated dark matter candidates from physics beyond the…
The exact composition of a specific class of compact stars, historically referred to as "neutron stars", is still quite unknown. Possibilities ranging from hadronic to quark degrees of freedom, including self-bound versions of the latter…
This proceeding broadly overviews the current landscape of heavy exotic spectroscopy. Such work includes the composition of certain X, Y , and Z states, and proceeds to discuss tetraquarks made exclusively of four quarks.
With the accumulation of experimental data, more and more exotic hadrons are observed. Among the interpretations of these exotic hadrons, molecular state and compact multiquark are two of the most popular pictures. However, it is still…
Hadron structure advances provided by the Coulomb gauge model are summarized. Highlights include a realistic description of the vacuum and meson spectrum with chiral symmetry and dynamical flavor mixing, accurate hyperfine splittings for…