  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 [Oliinychenko, Koch;
PRL 123, 18, 182302 (2019)] 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.
