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1.
《Physics letters. A》1997,235(4):375-378
Radiative corrections to the decay rate in low-Z hydrogen-like muonic atoms are considered. The correction is due to the Uehling potential and it has the relative order of α. The numerical results are reported for the 2p → 1s transition for atoms with nuclear charge up to Z = 10. 相似文献
2.
I. A. Goĭdenko 《Optics and Spectroscopy》2004,96(2):187-191
The quantum electrodynamic self-energy correction to the wave function in the effect of parity violation for the amplitude of the 6s–7s transition in the 133Cs atom is calculated in explicit form without using the nonrelativistic approximation for the self-energy operator. The result obtained refines some previous estimates and indicates that the correction to the parity violation may be comparable with the corresponding correction to the vacuum polarization. The necessity of taking complete relativistic account of all the quantum electrodynamic corrections in calculations of the electroweak charge Q W in atomic systems is shown. 相似文献
3.
S. Klarsfeld 《Physics letters. [Part B]》1977,66(1):86-88
Exact analytical expressions in terms of known transcendental functions are given for the evaluation of the Uehling vacuum-polarization potential induced by a static spherically-symmetrric charge distribution. 相似文献
4.
The problem of vacuum polarization by the Coulomb field of the nucleus and a constant homogeneous magnetic field is examined by the proper time method. For this the magnetic field is exactly taken into account, and the Coulomb field is considered by perturbation theory. In the case of a magnetic field equal to zero, we calculate the change of the Coulomb potential which results from vacuum polarization. The result obtained coincides with the well-known Uehling correction.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 86–92, September 1986. 相似文献
5.
G. Bonneau L. C. Costa J. L. Tomazelli 《International Journal of Theoretical Physics》2008,47(6):1764-1775
In this work we reconsider the one loop calculation for the vacuum polarisation tensor in the Lorentz violating quantum electrodynamics.
The electron propagator is “dressed” by a Lorentz breaking extra term in the fermion Lagrangian density. We check gauge invariance
and use the Schwinger–Dyson equation to discuss the full photon propagator. After a discussion on a possible photon mass shift,
we show how a finite quantum correction can be chosen in a unique way in order to ensure—in the spirit of spontaneously broken
theories—the standard normalisation conditions for the vacuum polarisation tensor. Then we comment on possible observable
physical consequences on the Lamb-shift. 相似文献
6.
S. Galster 《Zeitschrift für Physik A Hadrons and Nuclei》1961,161(1):46-61
The polarisation of the internal bremsstrahlung γ's was detected by the Compton-forward-scattering with polarised electrons for three differentβ-decays: 1. for the allowed transition (P32), 2. for the unique forbidden transition (Sr90+Y90), and 3. for the forbidden transition with forbidden spectrum (Bi210=RaE). The detected polarisation values of P32 and (Sr90+Y90) agree with the theoretical values for the allowed transitions. The detected polarisation values for Bi210 are smaller than the theoretical values of the allowedβ-transition by a factor of 0.62±0.08. The polarisation of the external bremsstrahlung was measured as a function of the atomic number (Z) using thick absorbers. The polarisation of the external bremsstrahlung decreases slowly with the increase of the atomic number. The polarisation of bremsstrahlung, which was extrapolated to an absorber with atomic numberZ=0, is in well agreement with the theoretical values of the infinitively thin absorbers. 相似文献
7.
C. Kalbach 《Zeitschrift für Physik A Hadrons and Nuclei》1989,332(2):157-161
A recent method for calculating particle-hole state densities is shown to be exact only when the number of excited particles equals the number of excited holes. Modifications are proposed for the cases wherep ≠ h. For thep=h case, comparisons of the exact results with the Williams analytical formula had pointed to inadequacies in the latter, but were made without considering the need for an energy dependent Pauli correction term. More careful investigation supports the continued use of the Williams formula with the appropriate Pauli correction term. 相似文献
8.
The effect of vacuum polarisation on internal conversion coefficients is investigated for the nuclear charge numbersZ=26 andZ=80; it contributes less than one percent to the conversion rate. 相似文献
9.
The thermodynamics and covariant kinetic theory are elaborately investigated in a non-extensive environment considering the non-extensive generalization of Bose–Einstein (BE) and Fermi–Dirac (FD) statistics. Starting with Tsallis’ entropy formula, the fundamental principles of thermostatistics are established for a grand canonical system having q-generalized BE/FD degrees of freedom. Many particle kinetic theory is set up in terms of the relativistic transport equation with q-generalized Uehling–Uhlenbeck collision term. The conservation laws are realized in terms of appropriate moments of the transport equation. The thermodynamic quantities are obtained in a weak non-extensive environment for a massive pion–nucleon and a massless quark–gluon system with non-zero baryon chemical potential. In order to get an estimate of the impact of non-extensivity on the system dynamics, the q-modified Debye mass and hence the q-modified effective coupling are estimated for a quark–gluon system. 相似文献
10.
11.
Two well-known quantum corrections to the area law have been introduced in the literatures, namely, logarithmic and power-law
corrections. Logarithmic corrections, arises from loop quantum gravity due to thermal equilibrium fluctuations and quantum
fluctuations, while, power-law correction appears in dealing with the entanglement of quantum fields in and out the horizon.
Inspired by Verlinde’s argument on the entropic force, and assuming the quantum corrected relation for the entropy, we propose
the entropic origin for the Coulomb’s law in this note. Also we investigate the Uehling potential as a radiative correction
to Coulomb potential in 1-loop order and show that for some value of distance the entropic corrections of the Coulomb’s law
is compatible with the vacuum-polarization correction in QED. So, we derive modified Coulomb’s law as well as the entropy
corrected Poisson’s equation which governing the evolution of the scalar potential ϕ. Our study further supports the unification of gravity and electromagnetic interactions based on the holographic principle. 相似文献
12.
We extend a theory of first order ? corrections to Gutzwiller’s trace formula for systems with a smooth potential to systems with discrete symmetries and, as an example, apply the method to the two-dimensional hydrogen atom in a uniform magnetic field. We exploit the C4v-symmetry of the system in the calculation of the correction terms. The numerical results for the semiclassical values will be compared with values extracted from exact quantum mechanical calculations. The comparison shows an excellent agreement and demonstrates the power of the ? expansion method. 相似文献
13.
T. Dohnalik 《Zeitschrift für Physik A Hadrons and Nuclei》1979,289(2):125-129
The shift of the atomic ground state due to the interaction with an external limited nonresonant laser field and vacuum fluctuation is calculated in resolvent formalism. The shift operator ¯R is taken to the fourth order of perturbation expansion. It is shown that the term which mixes these two interactions gives a slight correction to the total shift, which can be expressed by the Lamb shift of the excited state. 相似文献
14.
The correction to the Coulomb repulsion between two electrons due to the exchange of a transverse photon, referred to as the Breit interaction, as well as the main quantum electrodynamics contributions to the atomic energies (self-energy and vacuum polarization), are calculated using the recently formulated relativistic screened hydrogenic model. Comparison with the results of multiconfiguration Dirac-Hartree-Fock calculations and experimental X-ray energies is made. 相似文献
15.
Yu. M. Bystritskiy É. A. Kuraev A. V. Bogdan F. V. Ignatov G. V. Fedotovich 《JETP Letters》2006,83(2):51-53
A new definition is proposed for the hadronic contribution to the muon anomalous magnetic moment that is based on the inclusion of the effects of vacuum polarization by leptons into the cross section for one-photon annihilation of a lepton pair into hadrons. The formula for the hadronic contribution includes the convolution of the measured cross section for annihilation into hadrons with a certain standard function. This remark concerns radiative correction to this function. A particular form has been proposed for this correction. It has been shown that the use of the new function makes it possible to reduce the uncertainty in such contributions due to radiative correctioins to δa h/a h ~ 10?4. 相似文献
16.
S. Zschocke G. Plunien G. Soff 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(2):147-156
The renormalization method of Bogoljubov-Parasiuk-Hepp-Zimmermann (BPHZ) is used in order to derive the renormalized energy
shift due to the gauge invariant K?llén-Sabry diagram of the two-photon vacuum polarization (VPVP) as well as the self energy
vacuum polarization S(VP)E beyond the Uehling approximation. It is outlined, that no outer renormalization is required for
the two-photon vacuum polarization and that only the inner renormalization has to be accomplished. It is shown that the so-called
nongauge invariant spurious term is absent for a wide class of vacuum polarization (VP) diagrams if one applies the widely
used spherical expansion of bound and free-electron propagator. This simplifies significantly calculations in bound state
quantum electrodynamics. As one result of our paper the use of the BPHZ-approach in bound state QED is established.
Received 28 September 2001 相似文献
17.
U.D. Jentschura 《Annals of Physics》2011,(2):500-515
In view of the recently observed discrepancy of theory and experiment for muonic hydrogen [R. Pohl et al., Nature 466 (2010) 213], we reexamine the theory on which the quantum electrodynamic (QED) predictions are based. In particular, we update the theory of the 2P–2S Lamb shift, by calculating the self-energy of the bound muon in the full Coulomb + vacuum polarization (Uehling) potential. We also investigate the relativistic two-body corrections to the vacuum polarization shift, and we analyze the influence of the shape of the nuclear charge distribution on the proton radius determination. The uncertainty associated with the third Zemach moment 〈r3〉2 in the determination of the proton radius from the measurement is estimated. An updated theoretical prediction for the 2S–2P transition is given. 相似文献
18.
19.
S. Karshenboim U. Jentschura V. Ivanov G. Soff 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,2(3):209-215
We present an analytical evaluation of radiative corrections in exotic atoms induced by the one-loop electronic vacuum polarization.
We evaluate corrections to the energy levels, to the wave function (at the origin) and to the hyperfine structure. We treat
all corrections analytically within a non-relativistic approximation. Agreement is found with a few available numerical results.
The analytical treatment allows to determine the asymptotic forms of the corrections in the limit of a small atomic radius,
which for the atomic systems considered corresponds to a large mass of the constituent particle as compared to the electron
mass. The asymptotics can be verified using the effective charge approach.
Received: 28 January 1998 / Accepted: 13 March 1998 相似文献