Related papers: Spin-dependent interactions in quarkonia
We study spin-1/2 fermions in spin dependent potentials under the \emph{spin model approximation}, in which interatomic collisions that change the total occupation of single-particle modes are ignored. The spin model approximation maps the…
Experiments on quasi-one-dimensional systems such as quantum wires and metallic chains on surfaces suggest the existence of electron-electron interactions of substantial range and hence physics beyond the Hubbard model. We therefore…
We study the field dependence of the antiferromagnetic spin-1/2 Heisenberg model on the square lattice by means of exact diagonalizations. In a first part, we calculate the spin-wave velocity, the spin-stiffness, and the magnetic…
This manuscript is devoted to introduce a gauge theory of the Lorentz Group based on the ambiguity emerging in dealing with isometric diffeo-morphism-induced Lorentz transformations. The behaviors under local transformations of fermion…
A definition of an effective meson-meson interaction adapted to the framework of a lattice simulation is presented. Results, based on a truncated momentum-space 4-point time correlation matrix, and preliminary data from a complementary…
For a complete description of the physical properties of low-energy QCD, it might be advantageous to first reformulate QCD in terms of gauge-invariant dynamical variables, before applying any approximation schemes. Using a canonical…
We consider the massive integer higher spin fields coupled to an external constant electromagnetic field in flat space of arbitrary dimension and find a gauge invariant quartic interaction vertex which is quadratic in dynamical higher spin…
In this study, we explore the properties of quarkonia in a hot QCD medium using a newly proposed collision kernel that consistently incorporates the particle's momentum dependence into the relaxation time scale of the medium. The…
Relations connecting various zero momentum correlators of interpolating fields for pseudoscalar and scalar channel, containing one heavy and one light quark field, are derived from the Euclidean space formulation of the QCD functional…
Propagation of the heavy quark in the field of a static antiquark source is studied in the framework of effective Dirac equation. The model of QCD vacuum is described by bilocal gluonic correlators. In the heavy quark limit the effective…
We compute spin-dependent matrix elements for decays of S-wave quarkonia in lattice NRQCD. They appear to be in approximate agreement with the velocity-scaling rules of NRQCD.
We develop calculational tools to determine higher loop superstring correlators involving massless fermionic and spin fields in four space time dimensions. These correlation functions are basic ingredients for the calculation of loop…
The scalar-spinor interaction Lagrangian is presented by the Yukawa potential. In dS ambient space formalism, the interaction Lagrangian of scalar-spinor fields was obtained from a new transformation which is very similar to the guage…
In the framework of potential models for heavy quarkonium the mass spectrum for the system ($\bar b c$) is considered. Spin-dependent splittings, taking into account a change of a constant for effective Coulomb interaction between the…
We discuss the motion of spin in inertial and gravitational fields. The coupling of spin with rotation and the gravitomagnetic field has already been extensively studied; therefore, we focus here on the inertial and gravitational spin-orbit…
It has long been known that QCD undergoes a deconfining phase transition at high temperature. One of the consequent features of this new, quark-gluon phase is that hadrons become unbounded. In this talk meson correlation functions at…
For the first time, we determine the complete spin- and momentum-dependent order v^2 corrections to the static interquark potential from simulations of QCD in the valence quark approximation at inverse lattice spacings of 2-3 GeV. A new…
High-precision spectroscopy of muonic atoms provides a powerful probe for new short-range interactions predicted by theories beyond the Standard Model (SM). In this work, we derive new constraints on both spin-independent and spin-dependent…
A spin system on a lattice can usually be modelled at large scales by an effective quantum field theory. A key mathematical result relating the two descriptions is the quantum central limit theorem, which shows that certain spin observables…
We analyze the spin alignment of vector mesons stemming from spin correlation of the quark and antiquark induced by background color fields in relativistic heavy ion collisions. The quark-coalescence equation relating the collision kernel…