Recent results from the strong interaction program of the NA61/SHINE experiment and physics plans beyond 2020

The NA61/SHINE experiment at the CERN SPS studies hadron production properties in hadron-nucleus and nucleus–nucleus collisions. The experiment performs unique measurements for physics of strong interactions as well as important measurements for neutrino and cosmic-ray physics. Results from the strong interaction programme indicate a threshold for formation of large clusters interpreted as the onset of fireball. A scaled-factorial-moment analysis of the proton density fluctuations in Ar+Sc collisions at 150A GeV/c shows an intermittency signal, which may be a first trace of critical behavior. The main objective of the future NA61/SHINE program is to obtain high-precision data on charm hadron production. This new program is planned to start after 2020 and requires significant upgrades of the NA61/SHINE detector setup. Besides the construction of a large acceptance vertex detector, a 10-fold increase of the event recording rate is foreseen

Quest for toroidal freeze-out configuration in the central ^{197}Au + ^{197}Au collisions at 23 AMeV

We present the results of the experiment performed by the CHIMERA collaboration with the 4π CHIMERA array, for the system ^{197}Au + ^{197}Au at 23 AMeV. The experimental data are compared with ETNA and QMD model predictions. Efficiency factor is used as an indication of the formation of an exotic freeze-out configuration. Comparison between experimental data and model predictions may indicate the formation of flat/toroidal nuclear systems

Freeze-out configuration properties in the 197Au+197Au^{197}Au+^{197}Au reaction at 23 AMeV

We present the results of the experiment performed by the CHIMERA Collaboration with the $4\pi$ CHIMERA array, for the system $^{197}Au+^{197}Au$ at 23 AMeV. Conclusions related to the shape of the freeze-out configuration are drawn

On the formfactor of the imaginary part and its coupling to the real optical potential for the α\alpha-nucleus scattering

The model-independent formfactor of the absorptive cc-nucleus potential was calculated and compared with model dependent ones. The coupling between the shapes of the real and imaginary potential is discussed

Feasibility studies of open charm measurements with the NA61/SHINE experiment at CERN-SPS

The results of feasibility studies for the D_{0} meson (open charm) measurements by its decay into two daughter particles, pion and kaon, in central Pb–Pb collisions at SPS energies are presented. To generate the physical input we use AMPT (A Multi-Phase Transport model) event generator. We employ GEANT4 application to describe particle transport through the experimental setup. The study is done assuming NA61/SHINE detector system supplemented with a future Vertex Detector (VD), which allows for precise track reconstruction at the target proximity. This precision is needed to select pion and kaon pairs that originate from the D_{0} decays. The simulation results show that this measurement is feasible. This study also addresses the issue of vertex detector optimization with emphasis on the prospect of the development of a vertex detector based on CMOS technology

Dissipative orbiting in ^{136}Xe+^{209}Bi reactions at 28 and 62 AMeV

Correlations between the energy, charge and the deflection angle of the projectile-like fragments were studied for the ^{136}Xe + ^{209}Bi reaction at E∕A = 28 and 62 MeV. These correlations are seen to exhibit features characteristic of dissipative orbiting, commonly found at bombarding energies of a few MeV/nucleon above the interaction barrier, but also reported in the Fermi-energy domain. It was found, that in the studied bombarding energy range, the reaction cross section is still dominated by the dissipative binary reactions of well defined projectile- and target-like fragments

A novel experimental setup for rare events selection and its potential application to super-heavy elements search

The paper presents a novel instrumentation for rare events selection which was tested in our research of short-lived super-heavy elements production and detection. The instrumentation includes an active catcher multi-elements system and dedicated electronics. The active catcher located in the forward hemisphere is composed of 63 scintillator detection modules. Reaction products of damped collisions between heavy-ion projectiles and heavy-target nuclei are implanted in the fast plastic scintillators of the active catcher modules. The acquisition system trigger delivered by logical branch of the electronics allows to record the reaction products which decay via the alpha-particle emissions or spontaneous fission which take place between beam bursts. One microsecond wave form signal from FADCs contains information on heavy implanted nucleus as well as its decays

Investigation of the freeze-out configuration in the ^{197}Au + ^{197}Au reaction at 23 A MeV

According to the model predictions, observation of toroidal objects is expected in collisions of heavy ion at low incident energies. Comparison between experimental data and model predictions which may indicate the formation of flat/toroidal nuclear systems is shown

Competition between dynamical and sequential reaction channels in ^{197}Au+^{197}Au collisions at a bombarding energy of 23A MeV

Competition between the two reaction channels: sequential breakup and neck fragmentation has been studied in peripheral and semi-peripheral collisions of the 197 Au+ 197 Au system at bombarding energy of 23A MeV. It was found that the emission of heavy (A < 50) neck-originating fragments occurs in about 22% of ternary breakup events, making this reaction channel highly competitive with the sequential breakup of the projectile- or target-like fragment (78% of events)

Experimental search for super and hyper heavy nuclei at cyclotron Institute Texas A&M University

The question "How heavy can an atomic nucleus be?" is a fundamental problem in nuclear physics. The possible existence of island(s) of stable super-heavy nuclei has been an inspiring problem in heavy ion physics for almost four decades. This paper is focused on the experimental search of Super/Hyper Heavy Elements (SHE/HHE) conducted at the Cyclotron Institute, Texas A&M University. A novel experimental idea and experimental set up introduced for this research will be presented