EvoL: The new Padova T-SPH parallel code for cosmological simulations -
  I. Basic code: gravity and hydrodynamics
  We present EvoL, the new release of the Padova N-body code for cosmological
simulations of galaxy formation and evolution. In this paper, the basic Tree +
SPH code is presented and analysed, together with an overview on the software
architectures. EvoL is a flexible parallel Fortran95 code, specifically
designed for simulations of cosmological structure formation on cluster,
galactic and sub-galactic scales. EvoL is a fully Lagrangian self-adaptive
code, based on the classical Oct-tree and on the Smoothed Particle
Hydrodynamics algorithm. It includes special features such as adaptive
softening lengths with correcting extra-terms, and modern formulations of SPH
and artificial viscosity. It is designed to be run in parallel on multiple CPUs
to optimize the performance and save computational time. We describe the code
in detail, and present the results of a number of standard hydrodynamical
tests.
