Geometry and dynamics of relativistic collisions of heavy ions observed in correlations of registered particles in the STAR experiment

aim of project
The aim of this project is to study the time-spatial development of the emission process of particles in relativistic reactions of heavy ions by studying the correlations of hadrons emitted at low relative velocities in the STAR experiment conducted at Brookhaven National Laboratory (USA). Especially interesting are correlations of non-identical particles which enable to gain, otherwise unachievable, information on the time sequence of particle emission and their spatial asymmetry. The information plays a key role in understanding relations between collective and thermal moves in the expansion process of excited nuclear matter. A systematic analysis will be conducted for many two-particle combinations and in geometric and kinematic functions of parameters characterizing the studied phenomena and emitted particles. Data will come from subsequent measurements for different combinations of colliding nuclei and diff erent energies in mass centre according to the timetable of exposures at RHIC. It is also planned that the team will participate in work on development of theoretical models which enable a consistent description of specific stages of the process of heavy ions collision. This is to create a consistent description, the basis of which will be an approach based on equations of relativistic hydrodynamics but also taking into account production of resonances and processes occurring at the last stage of the reaction. Monte- -Carlo computer implementation will be elaborated, which will enable quantitative comparison of predictions from the model with the results of measurements. There will also be a quantitative comparative analysis for the obtained set of measurement data and model predictions.

expected results
The completion of the planned tasks will be a contribution to understanding the laws of nature at the level of the smallest elements of the matter. It will also be relevant to our understanding of phenomena occurring on the macro scale in connection with the Big Bang hypothesis and the early evolution of the universe. Tangible results will be presentations at international scientific conferences and publications in specialist journals. It is planned to organize scientific meetings on particles correlation and study of the time-spatial development of the process of heavy ions collision. A specific characteristic of the WUT team is a large percentage of young scientists, Ph.D. students, undergraduates at higher years and M.Sc. students. Many undergraduates and Ph.D. students regularly go abroad to institutions such as CERN, BNL, LBNL, numerous universities and scientific institutes within ongoing cooperation. Algorithms and computer programs developed by team members are part of basic software for experiments on heavy ions physics, they are also a great ”training area” during didactic classes conducted at the Faculty of Physics and a few other faculties of Warsaw University of Technology.