  To study the dependence of the equation of state of high density nuclear
matter on the term characterizing the isospin (proton-neutron) asymmetry of
nuclear matter, it is necessary to measure azimuthal flow of neutrons as well
as azimuthal flow of charged particles from a dense nuclear matter in the
nuclear-nuclear collisions. For this purpose INR RAS is developing a new
high-granular neutron detector which will be used in the BM@N experiment at the
extracted beam of the Nuclotron accelerator at JINR (Dubna). This detector will
identify neutrons and measure their energies in the heavy-ion collisions up to
4 GeV per nucleon.
  This article presents the results of measurements of the time resolution and
light yields of samples of scintillation detectors with sizes
40$\times$40$\times$25 mm$^3$ that will be used in a neutron detector based on
the currently available fast plastic scintillator manufactured by JINR using an
EQR15 11-6060D-S photodetector for light readout. For comparison, the results
of measurements for a detector of the same size with a fast scintillator EJ-230
and with the same type of photodetector are given. The measurements were made
on cosmic muons as well as on the electron synchrotron "Pakhra" of the Lebedev
Physical Institute of the Russian Academy of Sciences located in Troitsk,
Moscow.
