Nuclear structure dependence of the coherent (μ-,e-) conversion matrix elements

Coherent rates for the neutrinoless muon to electron conversion. (μ-, e-) in the presence of nuclei, are studied throughout the periodic table. The relevant ground state to ground state transition matrix elements are obtained in the context of the quasi-particle RPA. The results are discussed in view of the existing experimental data extracted at TRIUMF and PSI for 48Ti and 208Pb nuclei and compared with: (i) the single particle shell model results calculated with a determinantal ground state wave function and (ii) the results deduced in a local density approximation.

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Floquet-state cooling

Scientific Reports ◽

10.1038/s41598-019-53877-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Onno R. Diermann ◽

Martin Holthaus

Keyword(s):

Solid State ◽

Ground State ◽

Thermal Equilibrium ◽

Transition Matrix ◽

Fourier Spectrum ◽

Dissipative System ◽

Quasistationary State ◽

Matrix Elements ◽

Periodically Driven ◽

Transition Matrix Elements

AbstractWe demonstrate that a periodically driven quantum system can adopt a quasistationary state which is effectively much colder than a thermal reservoir it is coupled to, in the sense that certain Floquet states of the driven-dissipative system can carry much higher population than the ground state of the corresponding undriven system in thermal equilibrium. This is made possible by a rich Fourier spectrum of the system’s Floquet transition matrix elements, the components of which are addressed individually by a suitably peaked reservoir density of states. The effect is expected to be important for driven solid-state systems interacting with a phonon bath predominantly at well-defined frequencies.

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Computational strategy using improved virtual orbitals to ensure orthogonality of excited states to the ground state and to each other for calculation of transition matrix elements

International Journal of Quantum Chemistry ◽

10.1002/qua.560220856 ◽

2009 ◽

Vol 22 (S16) ◽

pp. 649-651

Author(s):

Joyce J. Kaufman

Keyword(s):

Excited States ◽

Ground State ◽

Transition Matrix ◽

Matrix Elements ◽

Transition Matrix Elements ◽

Computational Strategy ◽

Virtual Orbitals

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EVALUATION OF LINEAR AND NONLINEAR MICROSCOPIC POLARIZABILITIES OF C60

International Journal of Modern Physics B ◽

10.1142/s0217979292001973 ◽

1992 ◽

Vol 06 (23n24) ◽

pp. 3893-3901 ◽

Cited By ~ 13

Author(s):

Erik Westin ◽

Arne Rosén

Keyword(s):

Electronic Structure ◽

Local Field ◽

Ground State ◽

Reasonable Agreement ◽

Local Density ◽

Density Approximation ◽

Matrix Elements ◽

Yield Values ◽

Linear And Nonlinear ◽

Centrosymmetric Molecule

The electronic structure of C 60 and some of its doped compounds have earlier been investigated at the level of the local density approximation, LDA, using a numerical LCAO approach. In this study, single particle wavefunctions determined from ground state LDA calculations are used for evaluation of dipole matrix elements which combined with a sum over state approach yield linear and nonlinear microscopic polarizabilities γ(1) and γ(3), respectively. Lorentz local field factors, as well as a simple RPA type correction are introduced to facilitate comparison with the dielectric function ε(ω) determined from films of C 60. γ(2) for a centrosymmetric molecule such as C 60 is zero and the lowest non-zero contribution to the polarizability is γ(3). Reasonable agreement is found with results from linear optical response experiments i.e. ellipsometric and EELS measurements on C 60 in solid or solution form. SHG, THG and DFWM experiments yield values close to the unscreened result, while invoking a RPA screening results in a non-resonant value about 2 orders of magnitude lower than most experiments.

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Study of the exotic μ-e conversion in nuclei using RQRPA

HNPS Proceedings ◽

10.12681/hnps.2772 ◽

2020 ◽

Vol 9 ◽

pp. 1

Author(s):

Zhongzhu Ren ◽

A. Faessler ◽

T. S. Kosmas

Keyword(s):

Periodic Table ◽

Transition Matrix ◽

Random Phase Approximation ◽

Random Phase ◽

Pauli Principle ◽

Phase Approximation ◽

Matrix Elements ◽

Quasiparticle Random Phase Approximation ◽

Electron Conversion ◽

Transition Matrix Elements

The neutrinoless muon-to-electron conversion in nuclei is studied by using the renormalized quasiparticle random-phase approximation (RQRPA). This generalization of RPA is more reliable for the extremely small (μ-,e-) transition matrix elements than the ordinary QRPA because it restores the Pauli principle to a large extent. We apply the method to a set of nuclei throughout the periodic table, but we specifically investigate the 48Ti and 208Pb nuclei which are currently used as stopping targets at the PSI μ-e conversion experiments with the SINDRUM II spectrometer.

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OPTICAL TRANSITIONS IN A PARABOLIC GaAs/Ga1-xAlxAs SUPERLATTICES

Surface Review and Letters ◽

10.1142/s0218625x01001117 ◽

2001 ◽

Vol 08 (03n04) ◽

pp. 321-325

Author(s):

ŞAKIR ERKOÇ ◽

HATICE KÖKTEN

Keyword(s):

Transition Matrix ◽

Optical Transition ◽

Matrix Elements ◽

Electron States ◽

Parabolic Potential ◽

Consistent Field ◽

Self Consistent ◽

Self Consistent Field ◽

Transition Matrix Elements ◽

Scf Calculations

We have performed self-consistent field (SCF) calculations of the electronic structure of GaAs/Ga 1-x Al x As superlattices with parabolic potential profile within the effective mass theory. We have calculated the optical transition matrix elements involving transitions from the hole states to the electron states, and we have also computed the oscillator strength matrix elements for the transitions among the electron states.

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