Search

One of the alternatives to the Standard Model (SM) of elementary particles is the supersymmetry theories; the electric dipole moment (EDM) of elementary particles can serve as an excellent tool to confirm the validity of one of these models. For example: in the case of a neutron, the EDM, compatible with the SM, is within a range of to e cm, whereas the supersymmetry theories predict the presence of an EDM of much larger value, at the level of – e cm. Experiments on the search for EDM have been carried out for more than 50 years; however, most of them are based on charge-neutral particles (neutron, atoms). The EDM of charged particles (proton, deuteron) can be measured in a storage ring with the use of the phenomenon of the beam polarization precession in an electromagnetic field. The storage ring has a number of advantages when used as a tool for EDM measurement; however, there are also a number of problems. This paper discusses the main approaches to solving these problems: the BNL, spin wheel, and frequency domain methods. [ABSTRACT FROM AUTHOR]

The potential energy curves of 23 states of AlN radical are calculated to accurately determine the first several lowest-lying singlet and triplet states. The calculations are done using the CASSCF method, which is followed by the valence internally contracted MRCI approach. The rotationless radiative lifetimes of the vibrational levels are approximately 10−7–10−8 s for the C3Π, D3Π, and E3Δ states, 101–10−4 s for the A3Σ− state, and 10−4–10−5 s for the B3Σ+ state. The origins of the vibronic bands and the radiative lifetimes agree well with the available experimental and other theoretical results. The Einstein coefficients of many vibronic emissions are large for the C3Π–X3Π, C3Π–A3Σ−, D3Π–X3Π, D3Π–A3Σ−, and E3Δ–X3Π transitions and therefore, these transitions are strong. The emissions of the E3Δ–D3Π system are so weak that it is difficult to measure them through spectroscopy. The spectral distribution of the vibronic emissions is evaluated for the transitions of 12 pairs of states. In terms of the radiative lifetimes and transition probabilities obtained here, several spectroscopic routines for observing these states via spectroscopy are proposed. This paper calculates the potential energy curves, spectroscopic parameters, transition dipole moments, and transition probabilities of the AlN radical. The rotationless radiative lifetimes of the vibrational levels are of the order of 10−7 to 10−8 s for the C3Π, D3Π, and E3Δ states, 10−4 to 10−5 s for the B3Σ+ state, and 101 to 10−4 s for the A3Σ− state. The lifetimes of the C3Π, D3Π, and E3Δ states are almost determined by the C3Π–X3Π, D3Π–X3Π, D3Π–A3Σ, and E3Δ–X3Π systems, respectively. Overall, the C3Π–X3Π, C3Π–A3Σ−, D3Π–X3Π, and E3Δ–X3Π transitions, followed by the D3Π–A3Σ− and D3Π–C3Π transitions; the emissions are weak for the A3Σ−–X3Π, D3Π–B3Σ+, and E3Δ–D3Π systems. Curves of the TDM versus internuclear separation of 5pairs of states of the AlN. Unlabelled Image • Lifetimes are of the order of 10−7–10−8 s for the C3Π, D3Π, and E3Δ states. • C3Π–X3Π, C3Π–A3Σ−, D3Π–X3Π, D3Π–A3Σ−, and E3Δ–X3Π transitions are strong. • Lifetimes are 101–10−4 s for the A3Σ− state and 10−4–10−5 s for the B3Σ+ state. • Vibronic emissions of the E3Δ–D3Π system are weak. [ABSTRACT FROM AUTHOR]

This study calculates the potential energy curves of 12 Λ-S and 27 Ω states, which belong to the first dissociation channel of SiC + cation. The potential energy curves are computed with the complete active space self–consistent field method, which is followed by the valence internally multireference configuration interaction approach with the Davidson correction. The transition dipole moments are determined. Core-valence correlation and scalar relativistic correction, as well as extrapolation of the potential energies to the complete basis set limit are included. The spin-orbit coupling effect on the spectroscopic parameters and vibrational properties is evaluated. The vibrational band origins, Franck–Condon factors, and Einstein coefficients of spontaneous emissions are calculated. The rotationless radiative lifetimes of the vibrational levels are approximately 10 −5  s long for the e 2 Π state. The partial radiative lifetimes of vibrational levels are approximately 10 −7  s long for the 2 4 Π and 2 4 Σ − states, 10 −5 to 10 −6  s long for the 2 2 Σ − state and the first well of the 1 4 Π state, and very short for the second well of the 1 4 Π state. Overall, the emissions are strong for the 2 2 Σ − –c 2 Σ − , 2 4 Σ − –X 4 Σ − , 2 4 Π–X 4 Σ − transitions, and for the second well of the 1 4 Π–1 4 Σ + transition. The spectral range of emissions is determined. In terms of the radiative lifetimes and transition probabilities obtained in this paper, some guidelines for detecting these states are proposed via spectroscopy. These results can be used to measure the emissions from the SiC + cation, in particular, in interstellar clouds. [ABSTRACT FROM AUTHOR]

This study calculates the potential energy curves of 18 Λ-S and 50 Ω states, which arise from the C( 3 P g ) + P + ( 3 P g ) dissociation channel of the CP + cation. The calculations are made using the CASSCF method, followed by the icMRCI approach with the Davidson correction. Core-valence correlation and scalar relativistic corrections, as well as extrapolation to the complete basis set limit are included. The transition dipole moments are computed for 25 pairs of Λ-S states. The spin–orbit coupling effect on the spectroscopic and vibrational properties is evaluated. The Franck–Condon factors and Einstein coefficients of emissions are calculated. Radiative lifetimes are obtained for several vibrational levels of some states. The transitions are evaluated and spectroscopic measurement schemes for observing these Λ-S states are proposed. The potential energy curves, spectroscopic constants, vibrational levels, transition dipole moments, and transition probabilities reported in this paper can be considered to be very accurate and reliable. Because no experimental observations are currently available, the results obtained here can be used as guidelines for the detection of these states in appropriate spectroscopy experiments, in particular for observations in stellar atmospheres and in interstellar space. [ABSTRACT FROM AUTHOR]

A magnetic coil operated at cryogenic temperatures is used to produce spatial, relative field gradients below 6 ppm/cm, stable for several hours. The apparatus is a prototype of the magnetic components for a neutron electric dipole moment (nEDM) search, which will take place at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory using ultra-cold neutrons (UCN). That search requires a uniform magnetic field to mitigate systematic effects and obtain long polarization lifetimes for neutron spin precession measurements. This paper details upgrades to a previously described apparatus [1] , particularly the introduction of super-conducting magnetic shielding and the associated cryogenic apparatus. The magnetic gradients observed are sufficiently low for the nEDM search at SNS. [ABSTRACT FROM AUTHOR]

In this paper, we summarize the theoretical development on the electric dipole moment (CEDM) of light nuclei. We first describe the nucleon level CP violation and its parametrization. We then present the results of calculations of the EDM of light nuclei in the ab initio approach and in the cluster model. The analysis of the effect of several models beyond standard model (CBSM) is presented together with the prospects for its discovery. The advantage of the EDM of light nuclei is focused in the point of view of the many-body physics. The evaluations of the nuclear EDM generated by the -term and by the CP phase of the Cabibbo-Kobayashi-Maskawa (CKM) matrix are also reviewed. [ABSTRACT FROM AUTHOR]

This paper deals with the investigation results of nanocomposite permittivity based on magnetite nanoparticles and a polymeric matrix in electromagnetic field. Dependencies of real and imaginary parts of nanocomposite permittivity on the frequency of the electromagnetic field and size and concentration of magnetite nanoparticles have been found, and the dependence of imaginary part of permittivity on the real one has been determined. The Cole–Cole type has the dependence of the imaginary part of permittivity on the real one at high frequencies of electromagnetic field (at small values of the real part of permittivity) and hyperbolic behavior at small frequencies of the electromagnetic field (at large values of the real part of permittivity). Refraction index, loss angle tangent, and penetration depth of the nanocomposite. [ABSTRACT FROM AUTHOR]