International Journal of Modern Physics E

The aim of the AMADEUS collaboration is to provide new experimental constraints to the antikaon-nucleon ($\bar{K}N$) strong interaction in the regime of nonperturbative QCD, investigating the low-energy $K^{-}$ hadronic interactions with light nuclei like H, ⁴He, ⁹Be and ${}^{12}$C. The unique low-momentum kaon beam produced at the DA$\mathrm{\Phi }$NE collider is ideal to study $K^{-}$ nuclear captures, both at-rest and in-flight. The large acceptance KLOE detector, used as an active target, allows to achieve excellent position and momentum resolutions. In this work, a brief description of recent AMADEUS results is presented.

The ALICE Collaboration completed the upgrade of the detector and is now commissioning for the beginning of the data taking during LHC Run 3. In parallel, R&D activities and simulation studies are being performed to define the future of the experiment beyond LHC Run 3. Two detector upgrades are foreseen for the next long shutdown (LS3). The first is the replacement of the three layers of the inner tracking system closest to the beam with a novel vertex detector consisting of curved wafer-scale ultra-thin silicon sensors arranged in perfectly cylindrical layers to improve impact parameter resolution and significantly extend the physics capability for the study of the heavy-flavor production and the low-mass dielectrons. The second upgrade for the LS3 is the addition of a Forward Calorimeter detector at large rapidity consisting of a Si-W electromagnetic calorimeter with pad and pixel readout, that will equip the experiment with unique capabilities to measure small-x gluon distributions via prompt photon production. A proposal of a next-generation heavy-ion experiment for LHC Run 5 is also in preparation and will be discussed. The aim is to perform novel measurements of the electromagnetic and hadronic probes of the QGP, such as the production of multiply-charmed baryons, which have so far been inaccessible, both because of detector performance and luminosity. The concept of the new apparatus foresees an extensive usage of thin silicon sensors for tracking and a modern particle identification system, combining a silicon-based time of flight detector, a RICH detector, an electromagnetic calorimeter and a muon system.

The resonance peaks in cross-sections, related to the energy levels of compound nucleus, were believed to be one of the most significant features of the ⁶Li($n,t$), ³He($n,p$) and ⁷Be($n,p$) reactions. To explain the cross-sections with resonance peaks, the improved knockout model, which had been successfully applied to study the ⁶Li($n,t$) reaction in our previous work, was further employed to analyze the ³He($n,p$) and ⁷Be($n,p$) reactions. The effective excited energy formula, which can explain correlation between resonance peak and energy levels of the compound nucleus for the ⁶Li($n,t$) reaction, was extrapolated to the ³He($n,p$) and ⁷Be($n,p$) reactions. A more general form of the effective excited energy formula was proposed. The calculated angle-integrated cross-sections of the ³He($n,p$) and ⁷Be($n,p$) reactions agreed well with the experimental data. By combining our previous study on the ⁶Li($n,t$) reaction, the effects of energy levels of the compound nucleus on particle emission for these three reactions were reasonably illustrated.

In this paper, the emission features of singly-charged and doubly-charged projectile fragments emitted in interactions of ${}^{84}{\mathrm{\text{Kr}}}_{36}$ with emulsion at 1AGeV are studied. We have also observed the dependence of the singly-charged and doubly-charged projectile fragments on the interaction with different target groups of the emulsion detectors. The multi-source model can characterize the projectile fragments, and each source provides an exponential distribution, according to our calculations. The present observation shows that the emission features of the singly-charged and doubly-charged projectile fragments are independent on the interaction with different target groups of the emulsion.

One of the substantial successes achieved in nuclear physics in the last two decades was the synthesis of dozens of isotopes of new elements up to ${}_{118}$Og, which closed the seventh row of the periodic table and inspired the ambition of adding more elements. This work aims to study extensively the ground state structure and decay properties of proposed $Z=120$ isotopes. We employed Macroscopic–microscopic scheme based on the Skyrme energy density functional, the Woods–Saxon single-particle potential and Strutinsky’s method to find the structure properties, in a multidimensional deformation space. The same nucleon–nucleon potential is used to find the $\alpha$-decay half-life, within the Preformed Cluster Model. For 45 ${}^{270-314}$120 isotopes, the total energy surfaces, ground state masses, binding energy, deformations and fissionability are determined. The $Q$-values of the different competing decays and $\alpha$-decay half-lives are investigated based on the obtained structure. The results indicate the ${}^{294-300}$120 isotopes to be the most bound among the studied isotopes. The smallest fission barriers are indicated for the ${}^{285-294,296,313}$120 isotopes. The ${}^{294-304}$120 isotopes showed the longer half-lives against $\alpha$-decay, with an order of $\mu \mathrm{\text{s}}$. The longest half-lives are estimated for the ${}^{301}$120 ($3.7\pm 3.6\mu \mathrm{\text{s}})$ and ${}^{304}$120 ($1.1\pm 1.0\mu \mathrm{\text{s}})$ isotopes. The longest full decay chain ending with the stable ${}^{207}$Pb nucleus is anticipated for the ${}^{295}$120 isotope. The shortest decay chain of ${}^{296}$120 terminates after three $\alpha$-decays by the spontaneous fission of ${}^{284}$Fl.

In the framework of Glauber multiple scattering theory including the three-nucleon force, we can well describe the experimental measurements of deuteron–deuteron elastic scattering differential cross-section at momenta $1.75$, $2.12$, $2.2$ and $7.9$ GeV/c and center of mass energies $\sqrt{s}=53$ and $63$ GeV. Due to relatively small radius of three-nucleon force it has no effect in the forward direction where $q^2<0.2$ (GeV/c)² at any energy. The two-nucleon force is enough to describe the data where the single scattering terms are dominant. At medium energy, the effect of three-nucleon force is clear for $q^2\ge 0.2$ (GeV/c)². At the same time, for intersecting storage rings (ISR) energies, the three-nucleon force effect is clearly observed at the minimum of the differential cross-section and for the other values of $q^2>0.2$ (GeV/c)² is, in general, small.

The ground state properties including the density distributions of the neutrons, protons and matter as well as the corresponding root mean square (rms) radii of proton-rich halo candidates ⁸B, ${}^{12}$N, ${}^{23}$Al and ${}^{27}$P have been studied by the single particle Bear–Hodgson (BH) wave functions with the two-body model of $(\mathrm{\text{core}}+p)$. It is found that the rms radii of these proton-rich nuclei are reproduced well by this model and the radial wave functions describe the long tail of the proton and matter density distributions. These results indicate that this model achieves a suitable description of the possible halo structure. The plane wave Born approximation (PWBA) has been used to compute the elastic charge form factors.

In this paper, we develop a nonadiabatic collective model for even–even nuclei with effective triaxial quadrupole and octupole deformations. The model describes three-dimensional quadrupole–octupole rotation coupled with axial quadrupole–octupole vibrations. The moment-of-inertia tensor depends on the angular part of the polar coordinates in the quadrupole–octupole space, the values of which are determined from the ground state of the nucleus. In this model framework, the collective states of the yrast-alternating-parity band in the lanthanides ${}^{154}$Sm, ${}^{154,160}$Gd, ${}^{156}$Dy and the actinides ${}^{228,230,232}$Th, ${}^{230,232,236,238}$U, ${}^{238}$Pu are studied.

In this paper, a detailed study of the multiplicities of charged particles produced in $p$–$p$ collisions, at $\sqrt{s}=13$TeV, has been carried out. Analysis of UrQMD generated events along pseudo–rapidity ($\eta$), azimuthal angle ($\varphi$) and $\eta$-$\varphi$ phase spaces is made with the help of scaled factorial moment method. The results have also been compared with the UrQMD events with finite impact parameter ($b$) and minimum bias (MB) conditions. From the intermittency exponent (${\alpha }_q$), the anomalous fractal dimension $d_q$ is derived and the variations of $d_q$ with order $q$ are investigated. The observed intermittent fluctuations are manifested by various parameters such as anomalous fractal dimension $d_q$, degree of multifractality ($r$), critical exponent ($\nu$), Levy index ($\mu$) and multifractal specific heat. In the framework of Ginzburg–Landau theory, the second-order phase transition in the light of scaled factorial moment method has also been carried out to search for the quark-hadron phase transition. It is observed that the intermittent type of fluctuations are strong enough in $\eta$-$\varphi$ space compared to the one-dimensional $\eta$ space and $\varphi$ space. The data reflects the signature of multifractality in $\varphi$ space and $\eta$-$\varphi$ space. Whereas in case of $\eta$ space, it shows the evidence of monofractality. It is also interesting to note that the values of critical exponents for all impact parameters indicate the apparent existence of quark hadron phase transition except for MB events. However, no such behaviour is observed in $\varphi$ space. From the knowledge of generalized fractal dimension $D_q$, multifractal specific heat is derived from scale factorial moment analysis in case of one-dimensional $\eta$ space, $\varphi$ space and two-dimensional $\eta$-$\varphi$ space.

Many microscopic and macroscopic models are available in the literature to study the cluster radioactivity. The investigation of appropriate theoretical model to study the cluster decay process is an important aspect. We studied cluster-decay in the atomic and mass number range $87\le Z\le 96$ and $221\le A\le 242$ using modified generalized liquid drop model (MGLDM), Coulomb and proximity potential model (CPPM) and generalized liquid drop model (GLDM). The results obtained using macroscopic models are compared with that of microscopic models. There are various mass excess tables available in the literature. But indentification of suitable mass excess table for cluster radioactivity is an also important part of this study. The macroscopic models, such as MGLDM, CPPM and GLDM, were used to analyze cluster-decay half-lives. Along with this, microscopic and semi-empirical relations were also investigated. The standard deviation is evaluated in macroscopic, microscopic and semi-empirical formulae. A detailed investigation shows that among macroscopic model-MGLDM, macroscopic-RMFM and in case of semi-empirical formulae, AZF produces less deviation. Hence, these results give an insight into prediction of cluster decay half-lives in heavy and superheavy region for unknown nuclei.