Hadronic vacuum polarization in true muonium

Abstract A coherent study of e+e− annihilation into two (π+π−, K+K−) and three (π+π−π0, π+π−η) pseudoscalar meson production is carried out within the framework of resonance chiral theory in energy region E ≲ 2 GeV. The work of [L.Y. Dai, J. Portolés, and O. Shekhovtsova, Phys. Rev. D88 (2013) 056001] is revisited with the latest experimental data and a joint analysis of two pseudoscalar meson production. Hence, we evaluate the lowest order hadronic vacuum polarization contributions of those two and three pseudoscalar processes to the anomalous magnetic moment of the muon. We also estimate some higher-order additions led by the same hadronic vacuum polarization. Combined with the other contributions from the standard model, the theoretical prediction differs still by (21.6 ± 7.4) × 10−10 (2.9σ) from the experimental value.

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Vacuum Polarization in a Zero-Width Potential: Self-Adjoint Extension

Universe ◽

10.3390/universe7050127 ◽

2021 ◽

Vol 7 (5) ◽

pp. 127

Author(s):

Yuri V. Grats ◽

Pavel Spirin

Keyword(s):

Scalar Field ◽

Vacuum Polarization ◽

Dimensional Regularization ◽

Vacuum Expectation ◽

Vacuum Expectation Value ◽

Field Approximation ◽

Dimensional Euclidean Space ◽

Massless Scalar ◽

Massless Scalar Field ◽

Adjoint Extension

The effects of vacuum polarization associated with a massless scalar field near pointlike source with a zero-range potential in three spatial dimensions are analyzed. The “physical” approach consists in the usage of direct delta-potential as a model of pointlike interaction. We use the Perturbation theory in the Fourier space with dimensional regularization of the momentum integrals. In the weak-field approximation, we compute the effects of interest. The “mathematical” approach implies the self-adjoint extension technique. In the Quantum-Field-Theory framework we consider the massless scalar field in a 3-dimensional Euclidean space with an extracted point. With appropriate boundary conditions it is considered an adequate mathematical model for the description of a pointlike source. We compute the renormalized vacuum expectation value ⟨ϕ2(x)⟩ren of the field square and the renormalized vacuum averaged of the scalar-field’s energy-momentum tensor ⟨Tμν(x)⟩ren. For the physical interpretation of the extension parameter we compare these results with those of perturbative computations. In addition, we present some general formulae for vacuum polarization effects at large distances in the presence of an abstract weak potential with finite-sized compact support.

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Effect of massive quarks on the vacuum polarization of chiral currents

Physical Review D ◽

10.1103/physrevd.24.2724 ◽

1981 ◽

Vol 24 (10) ◽

pp. 2724-2729 ◽

Cited By ~ 3

Author(s):

Werner Wetzel ◽

Werner Bernreuther

Keyword(s):

Vacuum Polarization

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Vacuum polarization by solitons in (1+1) dimensions

Nuclear Physics B ◽

10.1016/0550-3213(94)90198-8 ◽

1994 ◽

Vol 428 (1-2) ◽

pp. 189-208 ◽

Cited By ~ 13

Author(s):

Siamak S. Gousheh ◽

Rafael López-Mobilia

Keyword(s):

Vacuum Polarization

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SECOND-ORDER CORRECTIONS TO QED COUPLING AT LOW TEMPERATURE

International Journal of Modern Physics A ◽

10.1142/s0217751x08041712 ◽

2008 ◽

Vol 23 (29) ◽

pp. 4709-4719 ◽

Cited By ~ 5

Author(s):

SAMINA S. MASOOD ◽

MAHNAZ HASEEB

Keyword(s):

Low Temperatures ◽

Vacuum Polarization ◽

Second Order ◽

Electromagnetic Properties ◽

Electron Mass ◽

Polarization Tensor ◽

Coupling Constant ◽

Electric Permittivity ◽

Thermal Medium ◽

Vacuum Polarization Tensor

We calculate the second-order corrections to vacuum polarization tensor of photons at low temperatures, i.e. T ≪ 1010 K (T ≪ me). The thermal contributions to the QED coupling constant are evaluated at temperatures below the electron mass that is T < me. Renormalization of QED at these temperatures has explicitly been checked. The electromagnetic properties of such a thermal medium are modified. Parameters like electric permittivity and magnetic permeability of such a medium are no more constant and become functions of temperature.

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