Resolution of SPD Detector in the Search for Dibaryons with Small Energy Excitations

Abstract

The existence of dibaryons, the systems with baryon number two, is one of the central questions in modern nuclear physics. It is closely connected with the problem of phase transitions in nuclear matter, various manifestations of which are being searched for in the experiments with colliding heavy nuclei. Since the theory of these processes is very difficult, the interpretation of such data usually contains large uncertainties. At the same time there is a possibility of understanding some features of these processes in the collision of the lightest nuclei–deuterons. Exploring such an opportunity at the future NICA SPD is the focus of this paper. It is shown that while using Kinematical fit technique at the simulation of the process \(d+d\rightarrow d+X\) below meson production threshold, the accuracy of the estimation of the \(X\) mass is on the level 2–3 MeV/\(c\) when the deuteron moment of the NICA Collider is equal to 2.6 GeV/c (below \(MX\) is used as a mass of \(X\), i.e. \(MX=M_{d}+E_{\textrm{exc}}\), where \(M_{d}\), \(E_{\textrm{exc}}\) are deuteron mass and excitation energy). The system \(X\) is called sometimes as dibaryons below.