相关论文: Pion Gas Viscosity
We perform a fit of the finite-volume QCD spectrum of three pions at maximal isospin to constrain the three-body force. We use the unitarity-based relativistic three-particle quantization condition, with the GWUQCD spectrum obtained at 315…
We calculate the electromagnetic contribution to the pion mass difference, $\Delta m^2_\pi=m^2_{\pi^+}-m^2_{\pi^0}$, in the chiral limit through the $VV-AA$ type vacuum polarization using Das-Guralnik-Mathur-Low-Young (DGMLY) sum rule. The…
The theoretical study of cross sections for polarized--target measurements of $ \pi N \to \pi \pi N $ reactions gives evidence that the interplay between the strong contribution from OPE mechanism and the one from isobar exchanges, which is…
We calculate the density profiles and density correlation functions of the one-dimensional Bose gas in a harmonic trap, using the exact finite-temperature solutions for the uniform case, and applying a local density approximation. The…
This work calculates the first correction to the leading order q\={q} dilepton production rates due to shear viscosity in an expanding gas. The modified rates are integrated over the space-time history of a viscous hydrodynamic simulation…
The pion nucleon vertex function at finite temperature is studied in the framework of: (a) the thermal (linear) sigma model to leading (one-loop) order, and (b) a thermal QCD-Finite Energy Sum Rule. Results from both methods indicate that…
We provide a novel approach to calculate the gravitational form factor of pion under the ladder approximation of the Bethe-Salpeter equation, with contact interactions. Central to this approach is a symmetry-preserving treatment of the…
We establish global-posedness in time for the viscous Boussinesq equations in two dimensions of space with temperature-dependent diffusivity in the framework of a smooth vortex patch. We also provide the inviscid limit for velocity,…
We study the propagation properties of the rho vector in a dense and hot pion medium. We introduce a finite value of the chemical potential associated to a conserved pion number and argue that such description is valid during the hadronic…
Pion and kaon mean free paths within a thermal hadronic background are calculated using relativistic kinetic theory. Free cross sections are used which include contributions from $\rho$, $K^{*}$, $\Delta$ and heavier resonances. Given pion…
We calculate the shear viscosity and anomalous baryon number violation rate in quantum field theories at finite temperature having gravity duals with hyperbolic horizons. We find the explicit dependence of these quantities on the…
We describe how the thermal counterpart of a vacuum two-point function may be obtained in the real time formalism in a simple way by using directly the $2\times 2$ matrices that different elements acquire in this formalism. Using this…
We investigate the chiral phase transition at finite temperatures and zero chemical potential with Dyson-Schwinger equations. Our truncation for the quark-gluon interaction includes mesonic degrees of freedom, which allows us to study the…
The ion temperature during magnetic reconnections measured along the direction of the magnetic field at the MST Reverse Field Pinch has not yet received a satisfactory theoretical explanation. In this work we argue that it is consistent…
We present precise path-integral Monte-Carlo results for the thermodynamics of a homogeneous dilute Bose gas. Pressure and energy are calculated as a function of temperature both below and above the Bose-Einstein transition. Specifically,…
We consider the Bose-Einstein condensation (BEC) in a relativistic pion gas. The thermodynamic limit when the system volume $V$ goes to infinity as well as the role of finite size effects are studied. At $V\to \infty$ the scaled variance…
We study in various chiral models the pion charge radius, $\pi_{e3}$ form factor ratio, $\pi^\circ \to \gamma \gamma$ amplitude, charge pion polarizabilities, $\gamma\gamma \to \pi^\circ \pi^\circ$ amplitude at low energies and the $\pi\pi$…
The transverse mass spectra and the rapidity distributions of $\pi^+$ and $\pi^-$ in Au-Au collisions at 2, 4, 6, and 8 GeV$\cdot$A by E895 collaboration are fitted using an elliptically expanding fireball model with the contribution from…
We study the effect of a finite volume for pion-pion scattering within Chiral Perturbation Theory (ChPT) and the Inverse Amplitude Method (IAM) in a $L^3$ box (rest frame). Our full ChPT calculation takes into account the discretization not…
We investigate the interaction effect between atoms and the finite size effect of a Bose-Einstein gas at finite temperature. Using a mean field approach, we derive the thermodynamic potential on finite systems and obtain the condensate…