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Related papers: Improved Bethe-Heitler formula

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We present a new perturbative formulation of non-equilibrium thermal field theory, based upon non-homogeneous free propagators and time-dependent vertices. The resulting time-dependent diagrammatic perturbation series are free of pinch…

High Energy Physics - Phenomenology · Physics 2013-07-31 Peter Millington , Apostolos Pilaftsis

The Thompson cross section for scattering of electromagnetic waves by a free electron in an expanding universe is derived here. The equations of motion of the electron are obtained using the Einstein-Infeld-Hoffmann (EIH) surface integral…

General Relativity and Quantum Cosmology · Physics 2007-05-23 James L. Anderson

Omission of Bohr's second postulate permits a derivation of spectral intensity. The transition amplitudes serve as upper bounds to quantum mechanical matrix elements. They also provide insight into the latter in terms of Sommerfeld ellipses…

History and Philosophy of Physics · Physics 2007-05-23 Manfred Bucher

A systematic investigation of hard thermal photon spectra from central ultra-relativistic heavy ion collisions is presented with emphasis on the effects of bremsstrahlung processes in the quark-gluon plasma (QGP). Bremsstrahlung photon…

Nuclear Theory · Physics 2007-05-23 Frank Daniel Steffen

We present a new perturbative formulation of non-equilibrium thermal field theory, based upon non-homogeneous free propagators and time-dependent vertices. The resulting time-dependent diagrammatic perturbation series are free of pinch…

High Energy Physics - Phenomenology · Physics 2013-07-31 Peter Millington , Apostolos Pilaftsis

The bremsstrahlung flux-averaged cross-sections $\langle{\sigma(E_{\rm{\gamma max}})}\rangle$ and the cross-sections per equivalent photon $\langle{\sigma(E_{\rm{\gamma max}})_{\rm{Q}}}\rangle$ were measured for the photonuclear…

Nuclear Experiment · Physics 2021-07-14 A. N. Vodin , O. S. Deiev , I. S. Timchenko , S. N. Olejnik

The perturbative framework is developed for the calculation of the pi(+)pi(-) atom characteristics (energy level shift and lifetime) on the basis of the field-theoretical Bethe-Salpeter approach. A closed expression for the first-order…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. E. Lyubovitskij , E. Z. Lipartia , A. G. Rusetsky

Invariant mass spectra of di-electrons stemming from bremsstrahlung processes are calculated in a covariant diagrammatical approach for the exclusive reaction D p \to p_{\rm sp} n p e^+ e^- with detection of a forward spectator proton,…

Nuclear Theory · Physics 2008-11-26 L. P. Kaptari , B. Kampfer

We present an analysis of the recent near threshold BESIII data for the nucleon time-like effective form factors. The damped oscillation emerging from the subtraction of the dipole formula is treated in non-perturbative-QCD, making use of…

High Energy Physics - Phenomenology · Physics 2024-07-12 Francesco Rosini , Simone Pacetti , Olga Shekhovtsova , Egle Tomasi-Gustafsson

This paper describes a computational model that self-consistently combines physics of kinetic electrons and atomic processes in a single framework. The formulation consists of a kinetic Vlasov- Boltzmann-Fokker-Planck equation for free…

Plasma Physics · Physics 2019-07-10 H. P. Le , M. Sherlock , H. A. Scott

According to the Schiff theorem, the atomic electrons completely screen the atomic nucleus from an external static electric field. However, this is not the case if the field is time-dependent. Electronic orbitals in atoms either shield the…

Atomic Physics · Physics 2019-01-30 H. B. Tran Tan , V. V. Flambaum , I. B. Samsonov

Improving perturbation theory via a variational optimization has generally produced in higher orders an embarrassingly large set of solutions, most of them unphysical (complex). We introduce an extension of the optimized perturbation method…

Soft Condensed Matter · Physics 2009-11-10 J. -L. Kneur , A. Neveu , M. B. Pinto

Phase and time delays of atomic above-threshold ionization are usually experimentally explored by the reconstruction of attosecond harmonic beating by interference of two-photon transitions (RABBIT) technique. Theoretical studies of RABBIT…

Atomic Physics · Physics 2024-03-25 Sebastián D. López , Matias L. Ocello , Diego G. Arbó

The cross section for bremsstrahlung from highly relativistic particles is suppressed due to interference caused by multiple scattering in dense media, and due to photon interactions with the electrons in all materials. We present here a…

The thermodynamic Bethe ansatz (TBA) and the excited state TBA equations for an integrable spin chain related to the Lie superalgebra osp(1|2) are proposed by the quantum transfer matrix (QTM) method. We introduce the fusion hierarchy of…

Mathematical Physics · Physics 2009-10-31 Kazumitsu Sakai , Zengo Tsuboi

The radiation reaction (beamstrahlung) effect on particle dynamics during interaction of oppositely charged beams is studied. It is shown that the beam focusing can be strongly enhanced due to beamstrahlung. An approximate analytical…

Accelerator Physics · Physics 2021-11-17 A. S. Samsonov , E. N. Nerush , I. Yu. Kostyukov , M. Filipovic , C. Baumann , A. Pukhov

Hard-photon (E$_{\gamma}>$ 30 MeV) emission from second-chance nucleon-nucleon Bremsstrahlung collisions in intermediate energy heavy-ion reactions is studied employing a realistic thermal model. Photon spectra and yields measured in…

We present a model for calculating broadened Autler-Townes spectra when probing ac electric field magnitudes by use of Rydberg atom electromagnetically-induced transparency. This model approximates the atom vapor as a multi-layered media…

Photon bremsstrahlung is proposed to be used to identify elastic proton-proton interactions at the LHC. In addition to a measurement of the elastic pp cross section (assuming that the elastic slope is known), the bremsstrahlung photons will…

High Energy Physics - Phenomenology · Physics 2011-02-02 V. A. Khoze , J. W. Lamsa , R. Orava , M. G. Ryskin

In this paper, we extend the study of bremsstrahlung photon production in a quark-gluon plasma to the cases of soft static photons and hard real photons. The general framework of this study is the effective perturbative expansion based on…

High Energy Physics - Phenomenology · Physics 2009-10-31 P. Aurenche , F. Gelis , R. Kobes , H. Zaraket