Related papers: Spin-dependent interactions in quarkonia
We discuss the central and, mostly, spin-dependent potentials in heavy quarkonia $\bar b b, \bar c c$, with two goals in mind. The first is phenomenological: using the splitting between the 1S and 2S pairs, as well as the 1P and 2P quartet…
According to the present understanding, the observed diversity of the strong interaction phenomena is described by Quantum Chromodynamics, a gauge field theory with only very few parameters. One of the fundamental questions in this context…
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…
We consider spatial correlation lengths \xi for various QCD light quark bilinears at temperatures above a few hundred MeV. Some of the correlation lengths (such as that related to baryon density) coincide with what has been measured earlier…
It is shown that the coefficient of the cubic interaction vertex, in higher spin Lagrangians, has a very simple form when written in terms of spinor helicity products. The result for a higher-spin field, of spin $\lambda$, is equal to the…
The spin alignment of $J/\psi$ with respect to event plane in relativistic heavy ion collisions exhibits a significant signal. We propose a possible mechanism for spin alignment through spin dependent dissociation of quarkonia in a vortical…
We present a phenomenological constraint on a pseudovector light boson beyond the Standard Model, which can induce a long-range spin-dependent interaction $\alpha^{\prime\prime}({\bf s}_1\cdot{\bf s}_2)\,{\rm e}^{-\lambda r}/r$. In the…
A model based on a nonrelativistic potential supplemented by spin dependent terms of the Breit-Fermi type is described. This model reproduces the known masses of the $\bar{b}b$ quarkonia within 1MeV and the known masses of the $\bar{c}c$…
We analyze how non-relativistic effective models for the magnetic coupling of a spin to the electromagnetic field (proportional to $\hat{\boldsymbol{\sigma}}\cdot \boldsymbol{B}$) emerge from a full quantum field theoretical description of…
Different mechanisms have been proposed to account for the spin-dependent interaction between quarks in ground-state hadrons. The first mechanism is the chromomagnetic interaction arising from one-gluon exchange, a second mechanism is an…
The nearest-neighbor quantum-antiferromagnetic (AF) Heisenberg model for spin 1/2 on a two-dimensional square lattice is studied in the auxiliary-fermion representation. Expressing spin operators by canonical fermionic particles requires a…
Nonperturbative spin-dependent forces of quarks in a baryon are calculated directly from the QCD Lagrangian in the framework of the Field Correlator Method both for heavy and light quarks. Resulting forces contain terms of 5 different…
Time-dependent spin phenomena in condensed matter are most often either described in the weakly correlated limit of metallic Stoner/Slater-like magnetism via band theory or in the strongly correlated limit of Heisenberg-like interacting…
We construct a nonrelativistic effective field theory description of heavy quarkonium hybrids from QCD. We identify the symmetries of the system made of a heavy quark, a heavy antiquark, and glue in the static limit. Corrections to this…
Recent experiments with dilute trapped Fermi gases observed that weak interactions can drastically modify spin transport dynamics and give rise to robust collective effects including global demagnetization, macroscopic spin waves, spin…
The spin-dependent corrections to the static interquark potential are relevant to describing the fine and hyper-fine splittings of the heavy quarkonium spectra. We investigate these corrections in SU(3) lattice gauge theory with the…
The exchange of spin-0 or spin-1 bosons between fermions or spin-polarised macroscopic objects gives rise to various spin-dependent potentials. We derive the coordinate-space non-relativistic potentials induced by the exchange of such…
Recent experimental data show an unexpectedly large spin alignment of $\phi$ mesons in high-energy heavy-ion collisions, which can be explained by short-distance fluctuations of strong-force fields (vector $\phi$ fields) within the…
In previous works, a squared mass operator M^2 and a more common centre of frame Hamiltonian H_CM for the quark-antiquark system were obtained by using the only assumption that ln W (W being the Wilson loop correlator) can be written in QCD…
A recently introduced relativistic nuclear energy density functional, constrained by features of low-energy QCD, is extended to describe the structure of hypernuclei. The density-dependent mean field and the spin-orbit potential of a…