abstract

We calculate BSM hadronic matrix elements for \(K^0\)–\(\bar K^0\) mixing in the Dual QCD approach (DQCD). The ETM, SWME and RBC-UKQCD lattice collaborations find the matrix elements of the BSM density–density operators \(\mathcal {O}_i\) with \(i=2\)–5 to be rather different from their vacuum insertion values (VIA) with \(B_2\approx 0.5\), \(B_3\approx B_5\approx 0.7\) and \(B_4\approx 0.9\) at \(\mu =3\) GeV to be compared with \(B_i=1\) in the VIA. We demonstrate that this pattern can be reconstructed within the DQCD through the non-perturbative meson evolution from very low scales, where factorization of matrix elements is valid, to scales \(\mathcal {O}\)(1 GeV) with subsequent perturbative quark–gluon evolution to \(\mu =3\) GeV. This turns out to be possible in spite of a very different pattern displayed at low scales with \(B_2=1.2\), \(B_3=3.0\), \(B_4=1.0\) and \(B_5\approx 0.2\) in the large-\(N\) limit, \(N\) being the number of colours. Our results imply that the inclusion of meson evolution in the phenomenology of any non-leptonic transition like \(K^0\)–\(\bar K^0\) mixing and \(K\to \pi \pi \) decays is mandatory. While meson evolution, as demonstrated in our paper, is hidden in lattice QCD results, to our knowledge, DQCD is the only analytic approach for non-leptonic transitions and decays which takes this important strong dynamics into account.

abstract

In this note, we discuss the rapidity dependence of the initial and final conditions for hydrodynamic evolution as well as the resulting basic hadronic observables in heavy-ion collisions at \(\sqrt {s_{NN}}=72\) GeV in the framework of a viscous hydrodynamic+cascade model vHLLE+UrQMD. The resulting rapidity dependences are driven to a big extent by the initial state, which is simulated with the UrQMD cascade. The results can serve as a prediction for future experiments such as the AFTER@LHC or the BES-II program at STAR.

abstract

The azimuthal angular decorrelation that is relevant to small-\(x\) QCD physics is studied in this paper to show the BFKL effect with a recent event generator. Events are generated at \(\sqrt {s} = 100\) TeV with proton–proton collisions and jets that are reconstructed by the anti-\(k_{\mathrm {T}}\) algorithm (\(R=0.7\)) with \(p_{\mathrm {T}}\gt 35\) GeV and in the rapidity range of \(|y|\lt 6\) are selected for the study. The azimuthal-angle difference between Mueller–Navelet jets (\(\Delta {\mit \Phi }\)) in the rapidity separation (\(\Delta y\)) up to \(12\) is analysed. The distributions of \(\langle \cos n(\pi -\Delta {\mit \Phi })\rangle \) for \(n=1,2,3\) and their ratios are also presented as a function of \(\Delta y\).

abstract

Band structures of \(^{99}\)Rh nucleus are discussed in framework of the spherical shell-model calculations using the \(jj\)45\(pna\) effective interaction. Level structures at low energies are identified as resulting from the rotational bands based on the \(\pi p_{1/2}\) and \(\pi g_{9/2}\) configurations. The lowest observed positive-parity state is 9/2\(^+\) and corresponds to wave function consisting of the \(\pi (p_{1/2}^{2}g_{9/2}^{5}\)) \(\otimes \) \(\nu (g_{7/2}^{2}d_{5/2}^{2}\)) configuration. Systematics of single-quasiparticle \(\pi p_{1/2}\) and \(\pi g_{9/2}\) bands in odd-\(A\) \(^{91-113}\)Rh isotopes along with the ground state bands in the corresponding even–even Ru core isotopes is discussed to bring out the role of spin–orbit partner orbitals for collectivity. The energy staggering plots for odd-\(A\) \(^{91-113}\)Rh isotopes are also discussed.

abstract

We identified and confirmed a low-energy (38 keV) \(\gamma \) transition in \(^{132}\)La by comparing the intensity ratio of La X rays. The state with spin \(7^{+}\), known as the multiplet of \(\pi h_{11/2}\otimes \nu h_{11/2}\), has further been investigated for its nature as isomeric. A negative parity band was closely observed in comparison with the neighboring isotones \(_{\,\,55}^{130}\)Cs\(_{75}\) and \(_{\,\,59}^{134}\)Pr\(_{75}\), and for the first time the configuration \(\pi d_{5/2}\otimes \nu h_{11/2}\) was assigned.

abstract

In this work, the aim is to study the spread of a contagious disease and information on a multilayer social system. The main idea is to find a criterion under which the adoption of the spreading information blocks or suppresses the epidemic spread. A two-layer network is the base of the model. The first layer describes the direct contact interactions, while the second layer is the information propagation layer. Both layers consist of the same nodes. The society consists of five different categories of individuals: susceptibles, infective, recovered, vaccinated and precautioned. Initially, only one infected individual starts transmitting the infection. Direct contact interactions spread the infection to the susceptibles. The information spreads through the second layer. The SIR model is employed for the infection spread, while the Bass equation models the adoption of information. The control parameters of the competition between the spread of information and spread of disease are the topology and the density of connectivity. The topology of the information layer is a scale-free network with increasing density of edges. In the contact layer, regular and scale-free networks with the same average degree per node are used interchangeably. The observation is that increasing complexity of the contact network reduces the role of individual awareness. If the contact layer consists of networks with limited range connections, or the edges sparser than the information network, spread of information plays a significant role in controlling the epidemics.

abstract

Most of the real-world networks are complex as well as evolving. Therefore, it is important to study the effect of network topology on the dynamics of traffic and congestion in the network. To account this problem, we have designed a time-varying network model where a new node will join a node in the existing network with probability proportional to its degree and disassortativity with its neighbors. Disassortativity quantifies the tendency of the node to connect with dissimilar node (in terms of degree) in the complex network. Betweenness centrality (BC) plays an important role in finding the influential node and user’s shortest route in the network. As the shortest route comprises of hub nodes and a chance of congestion is bigger on these nodes. Hence, BC–BC correlation is used to find user’s route. A connection between two hub nodes reduces the data forwarding capacity of connecting link with higher probability. If a node shows disassortativity with its neighbors, then it may forward more packets and may be chosen for routing. Furthermore, user’s optimal data sending rate as well as critical packet generation rate of the proposed model is calculated and shown improved results in comparison to the classical scale-free network model.