Modern Physics Letters A

The Alpha Magnetic Spectrometer is a particle physics detector focusing on the search for dark matter, the existence of antimatter, the origin and composition of cosmic rays from primordial sources in the universe and the exploration of new physics in space. Important features of the elementary particle (proton, antiproton, positron and election) fluxes in cosmic rays are presented: (1) The proton spectrum has a smooth hardening from 200 GeV; (2) antiproton and positron spectra show excess from traditional physics background; (3) in particular, the positron flux shows a source term with a cutoff energy of 810 GeV, which raises the question of its source; (4) the origin of the energetic electrons is different from that of positrons and (5) the identical momentum dependence of primary and secondary cosmic ray nuclei fluxes are also reviewed.

Numerical modeling of the deuteron wave function in the coordinate representation for the phenomenological nucleon–nucleon potential Argonne v18 has been performed. For this purpose, the asymptotic behavior of the radial wave function has been taken into account near the origin of coordinates and at infinity. The charge deuteron form factor $G_C(p)$, depending on the transmitted momentums up to $p=22{\mathrm{\text{fm}}}^{-1}$, has been calculated employing five models for the deuteron wave function. A characteristic difference in calculations of $G_C$ is observed near the positions of the first and second zero. The difference between the obtained values for $G_C$ form factor has been analyzed using the values of the ratios and differences for the results. Obtained outcomes for charge deuteron form factor at large momentums may be a prediction for future experimental data.

In this work, we study the dark energy accretion phenomena onto $(n+2)$-dimensional Schwarzschild black hole and $(n+2)$-dimensional Morris–Thorne wormhole. We obtain the $(n+2)$-dimensional Schwarzschild black hole mass and $(n+2)$-dimensional Morris–Thorne wormhole mass and their rate of change of masses due to accretion. For the dark energy component, we consider Tsallis, modified Rényi and “modified” Sharma–Mittal holographic dark energy (HDE) and new agegraphic dark energy (NADE). We also find the black hole mass and the wormhole mass in terms of redshift when cold dark matter and the specified forms of dark energies accrete onto them. In most cases, the black hole mass increases, and wormhole mass decreases for HDE and NADE accretions. The only exception is the Sharma–Mittal NADE, where the black hole mass decreases and wormhole mass increases during the evolution of the Universe. However, the slope of increasing/decreasing mass significantly depends on the dimension in almost all cases.

Dynamics of charged rotating BTZ black holes in 2 + 1 dimensions by using the cut and paste approach is discussed. Due to the mechanical stability of rotating charged BTZ thin shell, the radial perturbation about the equilibrium throat radius and three variable equation of state (EoS) is analyzed. Several examples are displayed satisfying it, such as variable Phantom-like, variable Chaplygin gas and variable modified generalized Chaplygin gas.

An anomaly observed in the ⁸Be nuclear transition by the Atomki collaboration hints at a light, neutral boson decaying into an $e^{+}{e}^{-}$ pair with a mass of about 17 MeV. In this paper, we study the Atomki anomaly in the framework of axial (ABJ) anomaly. Some theoretical results indicate that the X17 particle is the color singlet pseudoscalar. We take the X17 particle as a pseudoscalar meson $(uū)$ system which has the axial (ABJ) anomaly, where $u$ denotes the up quark. Besides this, we also give an interpretation for E38 particle with a mass of about 38 MeV as a pseudoscalar meson $(d\bar{d})$ system. We obtain the correct masses of the two pseudoscalars by a non-perturbative mass formula.

The cross-section of the ${}^{111}\mathrm{\text{Cd}}(n,n^{\prime }){}^{111\mathrm{\text{m}}}\mathrm{\text{Cd}}$ reaction was measured with ${}^{241}\mathrm{\text{Am/Be}}$ neutrons using a natural cadmium target $({}^{\mathrm{\text{nat}}}\mathrm{\text{Cd}})$. The neutron fluence and mean neutron energy of the source were determined using the ISO 8529-1 neutron spectrum and the known cross-sections of the monitor reaction ${}^{115}\mathrm{\text{In}}(n,n^{\prime }){}^{115\mathrm{\text{m}}}\mathrm{\text{In}}$. In order to measure the poor $\gamma$-ray activity of the reaction products, an HPGe detector with 70% detection efficiency surrounded by an adequate graded shield was applied. The efficiency calculations for the detector were performed using standard point calibration sources and the EFFTRAN efficiency code. Using the measured values of the neutron flux and the induced $\gamma$-ray activity of ${}^{111\mathrm{\text{m}}}\mathrm{\text{Cd}}$, the cross-section of the ${}^{111}\mathrm{\text{Cd}}(n,n^{\prime }){}^{111\mathrm{\text{m}}}\mathrm{\text{Cd}}$ reaction at the average neutron energy of 4.05 MeV was found to be $361\pm 21$ mb. An estimation of the contribution to the total cross-section by the accompanied reactions ${}^{110}\mathrm{\text{Cd}}(n,\gamma ){}^{111\mathrm{\text{m}}}\mathrm{\text{Cd}}$ and ${}^{112}\mathrm{\text{Cd}}(n,2n){}^{111\mathrm{\text{m}}}\mathrm{\text{Cd}}$ was achieved and the related cross-sections were found to be 0.16 mb and 8.99 mb, respectively.

In this work, we analyze the quantum dynamics of a generalized pendulum with a time-varying mass increasing exponentially and constant gravitation. By using Lewis–Riesenfeld invariant approach and Fock states, we solve the time-dependent Schrödinger equation for this system and write its solutions in terms of solutions of the Milne–Pinney equation. We also construct coherent states for the quantized pendulum and use both Fock and coherent states to investigate some important physical proprieties of the quantized pendulum such as eigenvalues of the angular displacement and momentum, their quantum variances as well as the respective uncertainty principle. Finally, we derive the geometric, dynamical and Berry phases for the time-dependent generalized pendulum.

Quantum contextuality, a more general quantum correlation, is an important resource for quantum computing and quantum information processing. Meanwhile, quantum contextuality plays an important role in fundamental quantum physics. Yu and Oh (YO) proposed a proof of the Kochen–Specker theorem for a qutrit with only 13 rays. Here, we further study quantum contextuality of YO-13 rays using the inequality approach. The maximum quantum violation value of the optimal noncontextuality inequality constructed by YO-13 rays is increased to 11.9776 in the four-dimensional system, which is larger than 11.6667 in the qutrit system. The result shows that the set of YO-13 rays has stronger quantum contextuality in the four-dimensional system. Moreover, we provide an all-versus-nothing proof (i.e. Hardy-like proof) to study YO-13 rays without using any inequality, which is easily applied to experimental tests. Our results will further deepen the understanding of YO-13 rays.

With the help of a semi-honest third party Calvin, n parties $P_1,P_2,\dots ,P_n$ can determine whether all of their private inputs $X_1,X_2,\dots ,X_n$ are equal or not without leaking any information. In this paper, we present a novel protocol using special quantum unitary operations and n-dimensional n-particle GHZ states. The proposed protocol is correct. It can also resist various outside attacks and overcome the problem of information leakage.