Физика высоких энергий

Novel method for searching critical vicinity of relativistic heavy-ion collision parameters, where dense hadronic matter transits into quark-gluon matter, and proposal for its implementation at the ВM@N and MPD experiments at the NICA accelerator complex

Experimental detection of the critical vicinity of the phase transition of dense hadronic matter into
quark-gluon matter is one of the main goals of the relativistic heavy-ion collisions physics. A novel
method for searching such a vicinity is proposed. Its essence is in selection of ultracentral collision
events, based on the azimuthal isotropy of the distribution of the particles produced in an event and
in search for the behaviour regime change of, for instance, two-dimensional dependence of a certain
observable on the collision energy and mass of one of the colliding nuclei. Location and size of the
critical vicinity can be estimated using an appropriate parametrization, while identification of the
phase transition will stem from the physical contents of the models, most adequately reproducing the
observed dependence, including the regime change. The advantage of the centrality criterion, based
on the azimuthal isotropy, — its independence, to a large extent, of the collision energy and of the
masses of the colliding nuclei, as well as of physics of the models, used for the method calibration, in
contrast to criteria, based on multiplicity.

Document number: 2018-2/893

Authors: A. N. Solomin

File size: 295.44 KB, updated 07.12.2018 14:42

GEOMETRICAL SPLITTING AND REDUCTION OF FEYNMAN DIAGRAMS

A geometrical approach to the calculation of N-point Feynman diagrams is reviewed. It is shown that the geometrical splitting yields useful connections between Feynman integrals with different momenta and masses. It is demonstrated how these results can be used to reduce the number of variables in the occurring functions.

Document number: 2016-2/890

Authors: Andrei I. Davydychev

File size: 309.12 KB, updated 13.05.2016 19:05

High-energy physics

High-energy physics plays an important role in physics institute. These studies have been conducted since the late 60's. The purpose of research is experimental and theoretical studies of the fundamental properties and laws of elementary particle interactions at high energy accelerators.

Read the rest of this entry »