$η$-pairing as a mechanism of superconductivity in models of strongly correlated electrons

$η$-superconductivity in the one-dimensionnal pair hopping model

$η$-trigonometric states of four qubits and entanglement measures

$η$-weak-Pseudo-Hermiticity generators and exact solvability

$η$-weak-pseudo-Hermiticity generators and radially symmetric Hamiltonians

$η'$ photoproduction on the nucleons in the quark model

$η'$ production in B-decays: Standard Model vs. New Physics

$η'$ production in proton-proton collisions far from the threshold

$η'$-$η_c$-mixing with improved stochastic estimators

$η'(η)\toγγ$: A Tale of Two Anomalies

$η'-g^*-g$ Transition Form Factor with Gluon Content Contribution Tested

$η'\toγγ$ and the topological susceptibility

$η- η'$ in a hot and dense medium

$η-η^\prime$ mixing and the next-to-leading-order power correction

$η-η^\prime$ Mixing in the Flavor Basis and Large N

$η-η^\prime$ Photoproduction and the Axial Isoscalar Neutral Current Coupling

$η-η^{\prime}$ Mixing Angle from Vector Meson Radiative Decays

$η-η^{\prime}$ Mixture in Chiral Bag

$η/s$ and Phase Transitions

$η/s$ of a Relativistic Hadron Gas at RHIC: Approaching the AdS/CFT bound?