Interaction of Intense Laser Beams with Electrons. Lowell S. Brown * and TWB Kibble Department of... more Interaction of Intense Laser Beams with Electrons. Lowell S. Brown * and TWB Kibble Department of Physics, Imperial College, London, England. Received 15 July 1963; revised 16 September 1963 The interaction of an intense ...
We calculate analytically the electron-ion temperature equilibration rate in a fully ionized, wea... more We calculate analytically the electron-ion temperature equilibration rate in a fully ionized, weakly to moderately coupled plasma, using an exact treatment of the Fermi-Dirac electrons. The temperature is sufficiently high so that the quantum-mechanical Born approximation to the scattering is valid. It should be emphasized that we do not build a model of the energy exchange mechanism, but rather, we perform a systematic first principles calculation of the energy exchange. At the heart of this calculation lies the method of dimensional continuation, a technique that we borrow from quantum field theory and use in a novel fashion to regulate the kinetic equations in a consistent manner. We can then perform a systematic perturbation expansion and thereby obtain a finite first-principles result to leading and next-to-leading order. Unlike model building, this systematic calculation yields an estimate of its own error and thus prescribes its domain of applicability. The calculational error is small for a weakly to moderately coupled plasma, for which our result is nearly exact. It should also be emphasized that our calculation becomes unreliable for a strongly coupled plasma, where the perturbative expansion that we employ breaks down, and one must then utilize model building and computer simulations. Besides providing new and potentially useful results, we use this calculation as an opportunity to explain the method of dimensional continuation in a pedagogical fashion. Interestingly, in the regime of relevance for many inertial confinement fusion experiments, the degeneracy corrections are comparable in size to the subleading quantum correction below the Born approximation. For consistency, we therefore present this subleading quantum-to-classical transition correction in addition to the degeneracy correction.
Stress-tensor trace anomaly in a gravitational metric: General theory, Maxwell field. Lowell S. B... more Stress-tensor trace anomaly in a gravitational metric: General theory, Maxwell field. Lowell S. Brown and James P. Cassidy Physics Department, University of Washington, Seattle, Washington 98195. Received 30 December 1976 ...
Summing tree graphs at threshold. Lowell S. Brown Department of Physics, FM-15, University of Was... more Summing tree graphs at threshold. Lowell S. Brown Department of Physics, FM-15, University of Washington, Seattle, Washington 98195. Received 1 September 1992 The solution of the classical field equation generates the sum of all tree graphs. ...
The emission of a hard photon by the electron or positron effectively puts the annihilation proce... more The emission of a hard photon by the electron or positron effectively puts the annihilation process in a moving frame. This mechanism causes an apparent correlation in the hadronic energy produced in the reaction. The dominant process involves the emission of a photon which is collinear with a lepton. We have calculated this contribution, which is of relative order ..cap
An asymptotic form for the high energy stopping number of E-electrons (for any element) is determ... more An asymptotic form for the high energy stopping number of E-electrons (for any element) is determined by using the Born approximation expressions for the excitation and ionization probabilities of the E shell. The stopping number takes the form B~(B, q) =A(8) lnrI+B(e)+C(8)(2/r})+. , where g is a dimensionless quantity proportional to the energy of the incident particle and 8 is proportional to the observed ionization energy of the E shell. Other results include the stopping number for hydrogen, obtained by sum-rule methods, to order (2/q), and results of M. C. Kalske, obtained by numerical methods, for the low energy stopping number of E-electrons.
A model theory (previously discussed by SCHWINGER) consisting of quantum electrodynamies with van... more A model theory (previously discussed by SCHWINGER) consisting of quantum electrodynamies with vanishing electron mass and in a space-time world of two dimensions is investigated with simple techniques. A complete solution is obtained, and it is found to be perfectly finite and to possess a massive single-particle state which may be interpreted as a massive photon. The noncommutativity of the charge and current densities at equal times plays a crucial role in the construction of the solution. Although the theory is invariant under constant Y5 gauge transformations, the corresponding chiral current is not conserved. The ~;cctor field analog to the electrodynamic model is also discussed. The consistent generation of the covariant field equations by the Hamiltonian is obtained by a careful definition of the bilinear products of charge fields which it contains. However, a consistent solution of the vector field model cannot be obtained with the methods successful in the electrodynamic case. 1.-Introduction.
Page 1. Page 2. Page 3. Quantum field theory is the basic theory of elementary particle physics. ... more Page 1. Page 2. Page 3. Quantum field theory is the basic theory of elementary particle physics. In recent years, many techniques have been developed which extend and clarify this theory. This book incorporates these modern ...
Precision spectroscopy of a charged particle in an imperfect Penning trap. Lowell S. Brown and Ge... more Precision spectroscopy of a charged particle in an imperfect Penning trap. Lowell S. Brown and Gerald Gabrielse Department of Physics, FM 15, University of Washington, Seattle, Washington 98195. Received 30 November 1981 ...
Interaction of Intense Laser Beams with Electrons. Lowell S. Brown * and TWB Kibble Department of... more Interaction of Intense Laser Beams with Electrons. Lowell S. Brown * and TWB Kibble Department of Physics, Imperial College, London, England. Received 15 July 1963; revised 16 September 1963 The interaction of an intense ...
We calculate analytically the electron-ion temperature equilibration rate in a fully ionized, wea... more We calculate analytically the electron-ion temperature equilibration rate in a fully ionized, weakly to moderately coupled plasma, using an exact treatment of the Fermi-Dirac electrons. The temperature is sufficiently high so that the quantum-mechanical Born approximation to the scattering is valid. It should be emphasized that we do not build a model of the energy exchange mechanism, but rather, we perform a systematic first principles calculation of the energy exchange. At the heart of this calculation lies the method of dimensional continuation, a technique that we borrow from quantum field theory and use in a novel fashion to regulate the kinetic equations in a consistent manner. We can then perform a systematic perturbation expansion and thereby obtain a finite first-principles result to leading and next-to-leading order. Unlike model building, this systematic calculation yields an estimate of its own error and thus prescribes its domain of applicability. The calculational error is small for a weakly to moderately coupled plasma, for which our result is nearly exact. It should also be emphasized that our calculation becomes unreliable for a strongly coupled plasma, where the perturbative expansion that we employ breaks down, and one must then utilize model building and computer simulations. Besides providing new and potentially useful results, we use this calculation as an opportunity to explain the method of dimensional continuation in a pedagogical fashion. Interestingly, in the regime of relevance for many inertial confinement fusion experiments, the degeneracy corrections are comparable in size to the subleading quantum correction below the Born approximation. For consistency, we therefore present this subleading quantum-to-classical transition correction in addition to the degeneracy correction.
Stress-tensor trace anomaly in a gravitational metric: General theory, Maxwell field. Lowell S. B... more Stress-tensor trace anomaly in a gravitational metric: General theory, Maxwell field. Lowell S. Brown and James P. Cassidy Physics Department, University of Washington, Seattle, Washington 98195. Received 30 December 1976 ...
Summing tree graphs at threshold. Lowell S. Brown Department of Physics, FM-15, University of Was... more Summing tree graphs at threshold. Lowell S. Brown Department of Physics, FM-15, University of Washington, Seattle, Washington 98195. Received 1 September 1992 The solution of the classical field equation generates the sum of all tree graphs. ...
The emission of a hard photon by the electron or positron effectively puts the annihilation proce... more The emission of a hard photon by the electron or positron effectively puts the annihilation process in a moving frame. This mechanism causes an apparent correlation in the hadronic energy produced in the reaction. The dominant process involves the emission of a photon which is collinear with a lepton. We have calculated this contribution, which is of relative order ..cap
An asymptotic form for the high energy stopping number of E-electrons (for any element) is determ... more An asymptotic form for the high energy stopping number of E-electrons (for any element) is determined by using the Born approximation expressions for the excitation and ionization probabilities of the E shell. The stopping number takes the form B~(B, q) =A(8) lnrI+B(e)+C(8)(2/r})+. , where g is a dimensionless quantity proportional to the energy of the incident particle and 8 is proportional to the observed ionization energy of the E shell. Other results include the stopping number for hydrogen, obtained by sum-rule methods, to order (2/q), and results of M. C. Kalske, obtained by numerical methods, for the low energy stopping number of E-electrons.
A model theory (previously discussed by SCHWINGER) consisting of quantum electrodynamies with van... more A model theory (previously discussed by SCHWINGER) consisting of quantum electrodynamies with vanishing electron mass and in a space-time world of two dimensions is investigated with simple techniques. A complete solution is obtained, and it is found to be perfectly finite and to possess a massive single-particle state which may be interpreted as a massive photon. The noncommutativity of the charge and current densities at equal times plays a crucial role in the construction of the solution. Although the theory is invariant under constant Y5 gauge transformations, the corresponding chiral current is not conserved. The ~;cctor field analog to the electrodynamic model is also discussed. The consistent generation of the covariant field equations by the Hamiltonian is obtained by a careful definition of the bilinear products of charge fields which it contains. However, a consistent solution of the vector field model cannot be obtained with the methods successful in the electrodynamic case. 1.-Introduction.
Page 1. Page 2. Page 3. Quantum field theory is the basic theory of elementary particle physics. ... more Page 1. Page 2. Page 3. Quantum field theory is the basic theory of elementary particle physics. In recent years, many techniques have been developed which extend and clarify this theory. This book incorporates these modern ...
Precision spectroscopy of a charged particle in an imperfect Penning trap. Lowell S. Brown and Ge... more Precision spectroscopy of a charged particle in an imperfect Penning trap. Lowell S. Brown and Gerald Gabrielse Department of Physics, FM 15, University of Washington, Seattle, Washington 98195. Received 30 November 1981 ...
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