1. |
- Bakker, B.L.G., et al.
(author)
-
Light-front quantum chromodynamics. A framework for the analysis of hadron physics
- 2014
-
In: Nuclear Physics B - Proceedings Supplements. - : Elsevier BV. - 0920-5632. ; 251-252, s. 165-174
-
Journal article (peer-reviewed)abstract
- An outstanding goal of physics is to find solutions that describe hadrons in the theory of strong interactions, Quantum Chromodynamics (QCD). For this goal, the light-front Hamiltonian formulation of QCD (LFQCD) is a complementary approach to the well-established lattice gauge method. LFQCD offers access to the hadrons' nonperturbative quark and gluon amplitudes, which are directly testable in experiments at existing and future facilities. We present an overview of the promises and challenges of LFQCD in the context of unsolved issues in QCD that require broadened and accelerated investigation. We identify specific goals of this approach and address its quantifiable uncertainties. © 2014 Elsevier B.V.
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2. |
- Behm, K. T., et al.
(author)
-
A spectrometer for ultrashort gamma-ray pulses with photon energies greater than 10 MeV
- 2018
-
In: Review of Scientific Instruments. - : AIP Publishing. - 1089-7623 .- 0034-6748. ; 89:11
-
Journal article (peer-reviewed)abstract
- © 2018 Author(s). We present a design for a pixelated scintillator based gamma-ray spectrometer for non-linear inverse Compton scattering experiments. By colliding a laser wakefield accelerated electron beam with a tightly focused, intense laser pulse, gamma-ray photons up to 100 MeV energies and with few femtosecond duration may be produced. To measure the energy spectrum and angular distribution, a 33 × 47 array of cesium-iodide crystals was oriented such that the 47 crystal length axis was parallel to the gamma-ray beam and the 33 crystal length axis was oriented in the vertical direction. Using an iterative deconvolution method similar to the YOGI code, modeling of the scintillator response using GEANT4 and fitting to a quantum Monte Carlo calculated photon spectrum, we are able to extract the gamma ray spectra generated by the inverse Compton interaction.
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3. |
- Cole, J. M., et al.
(author)
-
Experimental Evidence of Radiation Reaction in the Collision of a High-Intensity Laser Pulse with a Laser-Wakefield Accelerated Electron Beam
- 2018
-
In: Physical Review X. - 2160-3308. ; 8:1
-
Journal article (peer-reviewed)abstract
- The dynamics of energetic particles in strong electromagnetic fields can be heavily influenced by the energy loss arising from the emission of radiation during acceleration, known as radiation reaction. When interacting with a high-energy electron beam, today's lasers are sufficiently intense to explore the transition between the classical and quantum radiation reaction regimes. We present evidence of radiation reaction in the collision of an ultrarelativistic electron beam generated by laser-wakefield acceleration (μ 500 MeV) with an intense laser pulse (a0 > 10). We measure an energy loss in the postcollision electron spectrum that is correlated with the detected signal of hard photons (γ rays), consistent with a quantum description of radiation reaction. The generated γ rays have the highest energies yet reported from an all-optical inverse Compton scattering scheme, with critical energy > 30 MeV.
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4. |
- Dinu, V., et al.
(author)
-
Photon polarization in light-by-light scattering: Finite size effects
- 2014
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 90:4
-
Journal article (peer-reviewed)abstract
- We derive a simple expression for the photon helicity and polarization-flip probabilities in arbitrary background fields, in the low-energy regime. Taking the background to model a focused laser beam, we study the impact of pulse shape and collision geometry on the probabilities and on ellipticity signals of vacuum birefringence. We find that models which do not account for pulse duration can overestimate all signals in near head-on collisions by up to an order of magnitude. Taking pulse duration into account, the flip probability becomes relatively insensitive to both angular incidence and the fine details of the pulse structure.
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5. |
- Dinu, Victor, et al.
(author)
-
Quantum Radiation Reaction: From Interference to Incoherence
- 2016
-
In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 116:4
-
Journal article (peer-reviewed)abstract
- We investigate quantum radiation reaction in laser-electron interactions across different energy and intensity regimes. Using a fully quantum approach which also accounts exactly for the effect of the strong laser pulse on the electron motion, we identify in particular a regime in which radiation reaction is dominated by quantum interference. We find signatures of quantum radiation reaction in the electron spectra which have no classical analogue and which cannot be captured by the incoherent approximations typically used in the high-intensity regime. These signatures are measurable with presently available laser and accelerator technology.
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6. |
- Dinu, V., et al.
(author)
-
Vacuum refractive indices and helicity flip in strong-field QED
- 2014
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 89:12
-
Journal article (peer-reviewed)abstract
- Vacuum birefringence is governed by the amplitude for a photon to flip helicity or polarization state in an external field. Here, we calculate the flip and nonflip amplitudes in arbitrary plane wave backgrounds, along with the induced spacetime-dependent refractive indices of the vacuum. We compare the behavior of the amplitudes in the low energy and high energy regimes, and analyze the impact of pulse shape and energy. We also provide the first lightfront-QED derivation of the coefficients in the Heisenberg-Euler effective action.
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7. |
- Gonoskov, Arkady, et al.
(author)
-
Anomalous radiative trapping in laser fields of extreme intensity
- 2014
-
In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 113, s. 014801-
-
Journal article (peer-reviewed)abstract
- We demonstrate that charged particles in a suciently intense standing wave are compressed toward, and oscillate synchronously at, the antinodes of the electric eld. We call this unusualbehaviour `anomalous radiative trapping' (ART). We show using dipole pulses, which oer a pathto increased laser intensity, that ART opens up new possibilities for the generation of radiationand particle beams, both of which are high-energy, directed and collimated. ART also provides a mechanism for particle control in high-intensity quantum-electrodynamics experiments.
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8. |
- Gonoskov, Arkady, 1984, et al.
(author)
-
Extended particle-in-cell schemes for physics in ultrastrong laser fields : Review and developments
- 2015
-
In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - 1539-3755 .- 1550-2376. ; 92:2
-
Journal article (peer-reviewed)abstract
- We review common extensions of particle-in-cell (PIC) schemes which account for strong field phenomena in laser-plasma interactions. After describing the physical processes of interest and their numerical implementation, we provide solutions for several associated methodological and algorithmic problems. We propose a modified event generator that precisely models the entire spectrum of incoherent particle emission without any low-energy cutoff, and which imposes close to the weakest possible demands on the numerical time step. Based on this, we also develop an adaptive event generator that subdivides the time step for locally resolving QED events, allowing for efficient simulation of cascades. Further, we present a unified technical interface for including the processes of interest in different PIC implementations. Two PIC codes which support this interface, PICADOR and ELMIS, are also briefly reviewed.
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9. |
- Gonoskov, Arkady, et al.
(author)
-
Probing Nonperturbative QED with Optimally Focused Laser Pulses
- 2013
-
In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 111:6
-
Journal article (peer-reviewed)abstract
- We study nonperturbative pair production in intense, focused laser fields called e-dipole pulses. We address the conditions required, such as the quality of the vacuum, for reaching high intensities without initiating beam-depleting cascades, the number of pairs which can be created, and experimental detection of the created pairs. We find that e-dipole pulses offer an optimal method of investigating nonperturbative QED.
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10. |
- Gonoskov, Arkady, 1984, et al.
(author)
-
Ultrabright GeV Photon Source via Controlled Electromagnetic Cascades in Laser-Dipole Waves
- 2017
-
In: Physical Review X. - 2160-3308. ; 7:4
-
Journal article (peer-reviewed)abstract
- Electromagnetic cascades have the potential to act as a high-energy photon source of unprecedented brightness. Such a source would offer new experimental possibilities in fundamental science, but in the cascade process radiation reaction and rapid electron-positron plasma production seemingly restrict the efficient production of photons to sub-GeV energies. Here, we show how to overcome these energetic restrictions and how to create a directed GeV photon source, with unique capabilities as compared to existing sources. Our new source concept is based on a controlled interplay between the cascade and anomalous radiative trapping. Using specially designed advanced numerical models supported with analytical estimates, we demonstrate that the concept becomes feasible at laser powers of around 7 PW, which is accessible at soon-to-be-available facilities. A higher peak power of 40 PW can provide 10(9) photons with GeV energies in a well-collimated 3-fs beam, achieving peak brilliance 9 x 10(24) ph s(-1) mrad(-2) mm(-2)/0.1%BW.
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11. |
- Harvey, Christopher, 1982, et al.
(author)
-
Quantum Quenching of Radiation Losses in Short Laser Pulses
- 2017
-
In: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 118:10
-
Journal article (peer-reviewed)abstract
- Accelerated charges radiate, and therefore must lose energy. The impact of this energy loss on particle motion, called radiation reaction, becomes significant in intense-laser matter interactions, where it can reduce collision energies, hinder particle acceleration schemes, and is seemingly unavoidable. Here we show that this common belief breaks down in short laser pulses, and that energy losses and radiation reaction can be controlled and effectively switched off by appropriate tuning of the pulse length. This "quenching" of emission is impossible in classical physics, but becomes possible in QED due to the discrete nature of quantum emissions.
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12. |
- Harvey, Christopher, 1982, et al.
(author)
-
Testing numerical implementations of strong-field electrodynamics
- 2015
-
In: Physical Review A - Atomic, Molecular, and Optical Physics. - 2469-9926 .- 2469-9934. ; 91:1, s. Art. no. 013822-
-
Journal article (peer-reviewed)abstract
- We test current numerical implementations of laser-matter interactions by comparison with exact analytical results. Focusing on photon emission processes, it is found that the numerics accurately reproduce analytical emission spectra in all considered regimes, except for the harmonic structures often singled out as the most significant high-intensity (multiphoton) effects. We find that this discrepancy originates in the use of the locally constant field approximation.
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13. |
- Heinzl, T., et al.
(author)
-
Classical and quantum particle dynamics in univariate background fields
- 2016
-
In: Physical Review D. - 2470-0010 .- 2470-0029. ; 94:6
-
Journal article (peer-reviewed)abstract
- We investigate deviations from the plane wave model in the interaction of charged particles with strong electromagnetic fields. A general result is that integrability of the dynamics is lost when going from lightlike to timelike or spacelike field dependence. For a special scenario in the classical regime we show how the radiation spectrum in the spacelike (undulator) case becomes well-approximated by the plane wave model in the high-energy limit, despite the two systems being Lorentz inequivalent. In the quantum problem, there is no analogue of the WKB-exact Volkov solution. Nevertheless, WKB and uniform-WKB approaches give good approximations in all cases considered. Other approaches that reduce the underlying differential equations from second to first order are found to miss the correct physics for situations corresponding to barrier transmission and wide-angle scattering.
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14. |
- Heinzl, Thomas, et al.
(author)
-
Detecting radiation reaction at moderate laser intensities
- 2015
-
In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics. - 1539-3755 .- 1550-2376. ; 91:2
-
Journal article (peer-reviewed)abstract
- We propose a new method of detecting radiation reaction effects in the motion of particles subjected to laser pulses of moderate intensity and long duration. The effect becomes sizable for particles that gain almost no energy through the interaction with the laser pulse. Hence, there are regions of parameter space in which radiation reaction is actually the dominant influence on charged particle motion.
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15. |
- Homma, K., et al.
(author)
-
COMBINED LASER GAMMA EXPERIMENTS AT ELI-NP
- 2016
-
In: Romanian Reports on Physics. - 1221-1451 .- 1841-8759. ; 68, s. S233-S274
-
Journal article (peer-reviewed)abstract
- We propose experiments in the E7 and E4 experimental areas at ELI-NP to tackle problems of fundamental physics, taking advantage of the unique configuration and characteristics of the new research infrastructure to be constructed in Magurele, Romania. The experimental setups proposed follow a gradual approach from the point of view of complexity, from the "Day 1" experiments to experiments for which the prerequisites include results from the previously performed ones. In addition, there are two generic Research and Development tasks proposed in this Technical Design Report (TDR), related to the development of a detection system, Gamma Polari-Calorimeter (GPC), commonly applicable to energy measurements for electrons, positrons and gamma-rays above the 0.1 GeV energy scale and the preparatory tests for laser plasma acceleration of electrons up to necessary energies 210 MeV, 2.5 GeV and 5 GeV for the later stage experiments, respectively. In this paper we particularly focus on possible "Day-1" topics and briefly mention the future extensions foreseen.
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16. |
- Ilderton, Antony, 1978
(author)
-
Lightfront QED and Intense Field Physics
- 2014
-
In: Few-Body Systems. - : Springer Science and Business Media LLC. - 1432-5411 .- 0177-7963. ; 55:5-7, s. 493-499
-
Journal article (peer-reviewed)abstract
- We briefly review the particular relevance of lightfront quantisation to QED in external fields modelling intense lasers.
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17. |
- Ilderton, Antony, 1978
(author)
-
Localisation in worldline pair production and lightfront zero-modes
- 2014
-
In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479 .- 1126-6708. ; 2014:9, s. Art. no. 166-
-
Journal article (peer-reviewed)abstract
- The nonperturbative probability of pair production in electric fields depending on lightfront time is given exactly by the locally constant approximation. We explain this by showing that the worldline path integral defining the effective action contains a constraint, which localises contributing paths on hypersurfaces of constant lightfront time. These paths are lightfront zero-modes and there can be no pair production without them; the effective action vanishes if they are projected out.
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18. |
- Ilderton, Antony, 1978, et al.
(author)
-
Nonperturbative pair production in interpolating fields
- 2015
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 92:6, s. artikel nr 065001-
-
Journal article (peer-reviewed)abstract
- We compare the effects of timelike, lightlike and spacelike one-dimensional inhomogeneities on the probability of nonperturbative pair production in strong fields. Using interpolating coordinates we give a unifying picture in which the effect of the inhomogeneity is encoded in branch cuts and poles circulated by complex worldline instantons. For spacelike inhomogeneities the length of the cut is related to the existence of critical points, while for lightlike inhomogeneities the cut contracts to a pole and the instantons become contractible to points, leading to simplifications particular to the lightlike case. We calculate the effective action in fields with up to three nonzero components, and investigate its behavior under changes in field dependence.
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19. |
- Ilderton, Antony, 1978, et al.
(author)
-
Pair production from residues of complex worldline instantons
- 2015
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 92:2
-
Journal article (peer-reviewed)abstract
- We study nonperturbative pair production in electric fields with lightlike inhomogeneities, using complex worldline instantons. We show that the instanton contribution to the pair production probability is a complex contour integral over the instanton itself, and that pair production in the considered fields can be recast in terms of Cauchy's residue theorem. The instantons contribute residues from the poles they circulate (i.e. give local contributions), and the invariance of complex integrals under contour deformation manifests in the instanton contributions as invariance under a set of generalized, complex, reparametrizations.
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20. |
- Ilderton, Antony, 1978, et al.
(author)
-
Prospects for studying vacuum polarisation using dipole and synchrotron radiation
- 2016
-
In: Journal of Plasma Physics. - 0022-3778 .- 1469-7807. ; 82:2, s. 655820201-
-
Journal article (peer-reviewed)abstract
- The measurement of vacuum polarisation effects, in particular vacuum birefringence, using combined optical and X-ray laser pulses are now actively pursued. Here we briefly examine the feasibility of two alternative set-ups. The first utilises an alternative target, namely a converging dipole pulse, and the second uses an alternative probe, namely the synchrotron-like emission from highly energetic particles, themselves interacting with a laser pulse. The latter set-up has been proposed for experiments at ELI-NP.
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21. |
- Ilderton, Antony, 1978, et al.
(author)
-
Radiation reaction from QED: Lightfront perturbation theory in a plane wave background
- 2013
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 88:2
-
Journal article (peer-reviewed)abstract
- We derive dynamical, real time radiation reaction effects from lightfront QED. Combining the Hamiltonian formalism with a plane wave background field, the calculation is performed in the Furry picture for which the background is treated exactly while interactions between quantum fields are treated in perturbation theory as normal. We work to a fixed order in perturbation theory, but no other approximation is made. The literature contains many proposals for the correct classical equation describing a radiating particle; we take the classical limit of our results and identify which equations are consistent with QED.
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22. |
- Ilderton, Antony, 1978, et al.
(author)
-
Radiation reaction in strong field QED
- 2013
-
In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 725:4-5, s. 481-486
-
Journal article (peer-reviewed)abstract
- We derive radiation reaction from QED in a strong background field. We identify, in general, the diagrams and processes contributing to recoil effects in the average momentum of a scattered electron, using perturbation theory in the Furry picture: we work to lowest nontrivial order in a. For the explicit example of scattering in a plane wave background, we compare QED with classical electrodynamics in the limit h -> 0, finding agreement with the Lorentz-Abraham-Dirac and Landau-Lifshitz equations, and with Larmor's formula. The first quantum corrections are also presented.
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23. |
- Ilderton, Antony, 1978
(author)
-
Very special relativity as a background field theory
- 2016
-
In: Physical Review D. - 2470-0010 .- 2470-0029. ; 94:4
-
Journal article (peer-reviewed)abstract
- We consider violation of Lorentz invariance in QED induced by a very high frequency background wave. An effective theory is obtained by averaging observables over the rapid field oscillations. This preserves Ward identities and restores translation invariance below the high-frequency scale, but only partial Lorentz invariance: we show that the effective theory is C-invariant SIM(2)-QED in very special relativity. Averaging leads to the nonlocal terms familiar from SIM(2) theories, while the short-distance behavior of the background field fermion propagator generates the infinite number of higher-order vertices of SIM(2)-QED.
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24. |
- Ilderton, Antony, 1978, et al.
(author)
-
Worldline approach to helicity flip in plane waves
- 2016
-
In: Physical Review D. - 2470-0010 .- 2470-0029. ; 93:8
-
Journal article (peer-reviewed)abstract
- We apply worldline methods to the study of vacuum polarization effects in plane wave backgrounds, in both scalar and spinor QED. We calculate helicity-flip probabilities to one loop order and treated exactly in the background field, and provide a toolkit of methods for use in investigations of higher-order processes. We also discuss the connections between the worldline, S-matrix, and lightfront approaches to vacuum polarization effects.
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25. |
- Turcu, I. C. E., et al.
(author)
-
HIGH FIELD PHYSICS AND QED EXPERIMENTS AT ELI-NP
- 2016
-
In: Romanian Reports on Physics. - 1221-1451 .- 1841-8759. ; 68, s. S145-S231
-
Journal article (peer-reviewed)abstract
- ELI-NP facility will enable for the first time the use of two 10 PW laser beams for quantum electrodynamics (QED) experiments. The first beam will accelerate electrons to relativistic energies. The second beam will subject relativistic electrons to the strong electromagnetic field generating QED processes: intense gamma ray radiation and electron-positron pair formation. The laser beams will be focused to intensities above 10(21) Wcm(-2) and reaching 10(22)-10(23) Wcm(-2) for the first time. We propose to use this capability to investigate new physical phenomena at the interfaces of plasma, nuclear and particle physics at ELI-NP. This High Power Laser System Technical Design Report (HPLS-TDR2) presents the experimental area E6 at ELI-NP for investigating high field physics and quantum electrodynamics and the production of electron-positron-pairs and of energetic gamma-rays. The scientific community submitted 12 commissioning runs for E6 interaction chamber with two 10 PW laser beams and one proposal for the CETAL interaction chamber with 1 PW laser. The proposals are representative of the international high field physics community being written by 48 authors from 14 European and US organizations. The proposals are classified according to the science area investigated into: Radiation Reaction Physics: Classical and Quantum; Compton and Thomson Scattering Physics: Linear and Non Linear Regimes; QED in Vacuum; Atoms in Extreme Fields. Two pump-probe colliding 10 PW laser beams are proposed for the E6 interaction chamber. The focused pump laser beam accelerates the electrons to relativistic energies. The accelerated electron bunches interact with the very high electro-magnetic field of the focused probe laser beam. We propose two main types of experiments with: (a) gas targets in which the pump laser-beam is focused by a long focal length mirror and drives a wakefield in which the electron bunch is accelerated to multi-GeV energies and then exposed to the EM field of the probe laser which is tightly focused; (b) solid targets in which both the pump and probe laser beams are focused on the solid target, one accelerating the electrons in the solid and the other, delayed, providing the high electric field to which the relativistic electrons are subjected. We propose four main focusing configurations for the pump and probe laser beams, two for each type of target: counter-propagating 10 PW focused laser beams and the two 10 PW laser beams focused in the same direction. For solid targets we propose an additional configuration with plasma-mirror on the pump laser beam: the plasma mirror placed between the focusing mirror and target. It is proposed that the 10 PW laser beams will have polarization control and focus control by means of adaptive optics. Initially only one 10 PW may have polarization control and adaptive optics. In order to accommodate the two laser beams and diagnostics the proposed interaction chamber is quasi-octagonal with a diameter of 4.5 m. A large electron-spectrometer is proposed for multi-GeV electrons. Other diagnostics are requested for: gamma-rays, electrons and positrons, protons and ions, plasma characterization, transmitted and reflected laser beam. Targets will be provided by the ELI-NP Target Laboratory or purchased. The E6 experiments and diagnostics will benefit from the ELI-NP Electronics Laboratory, the Workshop and the Optics Laboratory. In order to ensure radiation-protection, a large beam-dump is planned for both multi-GeV electrons and multi-100 MeV protons.
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26. |
- Vary, James P., et al.
(author)
-
Applications of basis light-front quantization to QED
- 2014
-
In: Nuclear Physics B - Proceedings Supplements. - : Elsevier BV. - 0920-5632. ; 251-252, s. 10-15
-
Journal article (peer-reviewed)abstract
- Hamiltonian light-front quantum field theory provides a framework for calculating both static and dynamic properties of strongly interacting relativistic systems. Invariant masses, correlated parton amplitudes and time-dependent scattering amplitudes, possibly with strong external time-dependent fields, represent a few of the important applications. By choosing the light-front gauge and adopting an orthonormal basis function representation, we obtain a large, sparse, Hamiltonian matrix eigenvalue problem for mass eigenstates that we solve by adapting ab initio no-core methods of nuclear many-body theory. In the continuum limit, the infinite matrix limit, we recover full covariance. Guided by the symmetries of light-front quantized theory, we adopt a two-dimensional harmonic oscillator basis for transverse modes that corresponds with eigensolutions of the soft-wall anti-de Sitter/quantum chromodynamics (AdS/QCD) model obtained from light-front holography. We outline our approach and present results for non-linear Compton scattering, evaluated non-perturbatively, where a strong and time-dependent laser field accelerates the electron and produces states of higher invariant mass i.e. final states with photon emission. © 2014.
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27. |
- Zhao, X. B., et al.
(author)
-
Non-perturbative quantum time evolution on the light-front
- 2013
-
In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 726:4-5, s. 856-860
-
Journal article (peer-reviewed)abstract
- We introduce a covariant, nonperturbative, first principles numerical approach for solving time-dependent problems in quantum field theory. We demonstrate this approach by evaluating photon emission from an electron in a strong, time and space dependent external field. We study the acceleration of the electron in combination with the evolution of the invariant mass of the electron-photon system, in real time and at the amplitude level. Successive excitations of the electron-photon system are evident.
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28. |
- Zhao, X. B., et al.
(author)
-
Nonperturbative Quantum Field Evolution
- 2014
-
In: Few-Body Systems. - : Springer Science and Business Media LLC. - 1432-5411 .- 0177-7963. ; 55:5-7, s. 555-560
-
Journal article (peer-reviewed)abstract
- We introduce a nonperturbative, first-principles approach to time-dependent problems in quantum field theory. In this approach, the time-evolution of quantum field configurations is calculated in real time and at the amplitude level. This method is particularly suitable for treating systems interacting with a time-dependent background field. As a test problem, we apply this approach to QED and study electron acceleration and the associated photon emission in a time- and space-dependent electromagnetic background field.
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29. |
- Zhao, X. B., et al.
(author)
-
Scattering in time-dependent basis light-front quantization
- 2013
-
In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 88:6
-
Journal article (peer-reviewed)abstract
- We introduce a nonperturbative, first-principles numerical approach for solving time-dependent problems in quantum field theory, using light-front quantization. As a first application we consider QED in a strong background field, and the process of nonlinear Compton scattering in which an electron is excited by the background and emits a photon. We track the evolution of the quantum state as a function of time. Observables, such as the invariant mass of the electron-photon pair, are first checked against results from perturbation theory, for suitable parameters. We then proceed to a test case in the strong background field regime and discuss the various nonperturbative effects revealed by the approach.
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