abstract

As an alternative to reactor-based \(^{99}\)Mo/\(^{99m}\)Tc generator technology, many research groups have suggested the direct production of \(^{99m}\)Tc on highly enriched \(^{100}\)Mo through accelerators. For proton-induced reaction, there is a large discrepancy in 9–26 MeV beam energy range in the data available for the production of radionuclides impurities. In this work, we studied target yield and the cross section for the production of long-lived radionuclides produced in the \(^{\rm nat}\)Mo target irradiated with a proton beam of energy degraded from 26 to 19 MeV in the target. This constitutes the first step, which is a commissioning of the setup and a check of the method at the beam energy where cross sections of interest are large. The step was necessary before proceeding with more demanding measurements at lower energies. Target yield was derived using the measured activity of produced radionuclides. Total cross sections for all isotopes produced from \(^{\rm nat}\)Mo\((p,x)\) reactions are presented and compared with the previously available data, showing good agreement.

abstract

The anomalous neutral triple-gauge boson couplings (aNTGCs) for the \(Z\gamma \gamma \) and \(Z\gamma Z\) vertices described by dimension-eight operators are examined through the process \(pp\to l^{+}l^{-}\gamma \) at High-Luminosity Large Hadron Collider (HL-LHC). We performed an analysis on transverse momentum of photon and angular distribution of charged lepton in the final state including detector effects. Sensitivity limits of the \(C_{\tilde {B}W}\), \(C_{BB}\) couplings are obtained at \(95\%\) C.L. to constrain for the ranges \([-1.88;1.88]\) TeV\(^{-4}\), \([-1.47:1.47]\) TeV\(^{-4}\) and \([-1.14:1.14]\) TeV\(^{-4}\), \([-0.86;0.86]\) TeV\(^{-4}\) with an integrated luminosity of \(300\) fb\(^{-1}\) and \(3000\) fb\(^{-1}\), respectively.

abstract

We study the Wheeler–DeWitt (WDW) equation close to the Big Bang. We argue that an interaction-dominated fluid (speed of sound equal to the speed of light), if present, would dominate during such an early phase. Such a fluid with \(p=\rho \propto 1/a^{6}\) generates a term in the potential of the wave function of the WDW equation proportional to \(-1/a^{2}\). This very peculiar potential, which embodies a spontaneous breaking of dilatation invariance, has some very remarkable consequences for the wave function of the Universe: \({\mit \Psi }(a)\) vanishes at the Big Bang: \({\mit \Psi }(0)=0\); the wave function \({\mit \Psi }(a)\) is always real; a superselection rule assures that the system is confined to \(a\geq 0\) without the need of imposing any additional artificial barrier for unphysical negative \(a\). These results are valid for a continuous class of choices of the operator ordering of the WDW equation.

abstract

We consider Einstein–Cartan’s theory in the static spherically symmetric case with a completely antisymmetric torsion tensor. We show, in particular, that the weak Gauss law of general relativity is broken.

abstract

Multiplex networks consist of a fixed set of nodes connected by several sets of edges which are generated separately and correspond to different networks (“layers”). In this paper, the Ising model is considered on multiplex networks with two layers with partial overlap, i.e. , sharing only a part of nodes, with spins located in the nodes and edges corresponding to non-zero exchange integrals of ferromagnetic interactions. Critical temperature for the ferromagnetic transition is evaluated using heterogeneous mean-field approximation and the replica method, from the replica-symmetric solution. The results are valid for layers in the form of general complex networks, in particular for heterogeneous scale-free networks. The size of the overlap and the correlation between the degrees within different layers of nodes belonging to the overlap significantly influence the critical temperature. It is also argued that in typical cases, the size of the overlap does not influence the critical exponent for the ferromagnetic transition. Analytic predictions are partly confirmed by numerical simulations.

abstract

Synchronization in globally coupled Lozi maps has been investigated, when one of the parameters of the Lozi maps, \(\alpha \), is forced to vary periodically. Interestingly, it is observed that due to the variation of the parameter with time, the transition from desynchronized state to synchronized state occurs at lower values of global coupling strength. The synchronized and desynchronized state of CML are distinguished with the help of two statistical quantities: the average fraction of elements belonging to clusters and the standard deviation of the state variables averaged over different realisation of initial conditions. The transition of the system to the synchronised state in globally coupled Lozi map under parametric excitation will be helpful for better way of achieving the synchronised state in the case of various natural and well-known examples of synchronising systems.