We discuss the impact of magnetic field on the mass – temperature relation for groups and clusters of galaxies based on the derivation of the general Magnetic Virial Theorem. The presence of a magnetic field B yields a decrease of the virial temperature T for a fixed mass M : such a decrease in T is stronger for low-mass systems than for high-mass systems. We outline several implications of the...

We use the virial theorem to derive a closed analytic form of the Helmholtz free energy for a polydisperse system of sticky hard spheres (SHS) within the mean spherical model (MSM). To this end we calculate the free energy of the MSM for an N-component mixture of SHS via the virial route and apply to it-after imposing a Lorentz-Berthelot type rule on the interactions-the stochastic (i.e., polyd...

The formalism of the heavy quark effective theory is used to derive the field-theory analog of the virial theorem, which relates the matrix element of the kinetic energy of a heavy quark inside a hadron to a matrix element of the gluon field strength tensor. The existing QCD sum rule calculations of the kinetic energy are not consistent with this theorem. (submitted to Physics Letters B)

We derive a class of mesoscopic virial equations governing energy partition between conjugate position and momentum variables of individual degrees of freedom. They are shown to apply to a wide range of nonequilibrium steady states with stochastic (Langevin) and deterministic (Nosé–Hoover) dynamics, and to extend to collective modes for models of heat-conducting lattices. A macroscopic virial t...

We present CO 1→0 and 2→1 observations of the dwarf starburst galaxy NGC 1569 with the IRAM interferometer on Plateau de Bure. We find the CO emission is not spatially associated with the two super star clusters in the galaxy, but rather is found in the vicinity of an HII region. With the resolution of our data, we can resolve the CO emission into five distinct giant molecular clouds, four are ...

We study the stability properties of isolated star forming dwarf galaxies which undergo dynamically driven star bursts induced by stellar feedback. Here we focus on the impact of the adopted ISM model, i.e. either a diffuse or a clumpy ISM. We apply a one-zone model extended for active dynamical evolution. This allows for a coupling between the dynamical state of the galaxy and its internal pro...

We consider a quantum system composed of a small part, having finitely many degrees of freedom, interacting with a free, spatially infinitely extended Bose gas. An equilibrium state for the uncoupled system is given by the product state where the small part is in the Gibbs state at some temperature T > 0, and the Bose gas is in a state where a spatially homogeneous Bose-Einstein Condensate is i...