Effects of local event-by-event conservation laws in ultrarelativistic heavy-ion collisions at particlization

Many simulations of relativistic heavy-ion collisions involve the switching from relativistic hydrodynamics to kinetic particle transport. This switching entails the sampling of particles from the distribution of energy, momentum, and conserved currents provided by hydrodynamics. Usually, this sampling ensures the conservation of these quantities only on the average, i.e., the conserved quantities may actually fluctuate among the sampled particle configurations and only their averages over many such configurations agree with their values from hydrodynamics. Here we apply a recently invented method [D. Oliinychenko and V. Koch, Phys. Rev. Lett. 123, 182302 (2019)PRLTAO0031-900710.1103/PhysRevLett.123.182302] to ensure conservation laws for each sampled configuration in spatially compact regions (patches) and study their effects: From the well-known (micro-)canonical suppression of means and variances to little studied (micro-)canonical correlations and higher-order fluctuations. Most of these effects are sensitive to the patch size. Many of them do not disappear even in the thermodynamic limit, when the patch size goes to infinity. The developed method is essential for particlization of stochastic hydrodynamics. It is useful for studying the chiral magnetic effect, small systems, and in general for fluctuation and correlation observables

Superconducting properties of Gd-Ba-Cu-O single grains processed from a new, Ba-rich precursor compound

Gd-Ba-Cu-O (GdBCO) single grains have been previously melt-processed successfully in air using a generic Mg-Nd-Ba-Cu-O (Mg-NdBCO) seed crystal. Previous research has revealed that the addition of a small amount of BaO2 to the precursor powders prior to melt processing can suppress the formation of Gd/Ba solid solution, and lead to a significant improvement in superconducting properties of the single grains. Research into the effects of a higher Ba content on single grain growth, however, has been limited by the relatively small grain size in the earlier studies. This has been addressed by developing Ba-rich precursor compounds Gd-163 and Gd-143, fabricated specifically to enable the presence of greater concentrations of Ba during the melt process. In this study, we propose a new processing route for the fabrication of high performance GdBCO single grain bulk superconductors in air by enriching the precursor powder with these new Ba rich compounds. The influence of the addition of the new compounds on the microstructures and superconducting properties of GdBCO single grains is reported

Left-Right Asymmetry of Weak Interaction Mass of Polarized Fermions in Flight

The left-right polarization-dependent asymmetry of the weak interaction mass is investigated. Based on the Standard Model, the calculation shows that the weak interaction mass of left-handed polarized fermions is always greater than that of right-handed polarized fermions in flight with the same velocity in any inertial frame. The asymmetry of the weak interaction mass might be very important to the investigation of neutrino mass and would have an important significance for understanding the parity nonconservation in weak interactions.Comment: 8 pages, 2 figures, corrected calculatio