排序方式: 共有61条查询结果,搜索用时 712 毫秒
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Radiophysics and Quantum Electronics - We use the qualitative, simplified modeling, and approximately self-consistent nonlinear-optical approaches to explain the nature of the regime under which... 相似文献
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Glazyrin S. I. Lykov V. A. Karpov S. A. Karlykhanov N. G. Gryaznykh D. A. Bychenkov V. Yu. 《JETP Letters》2022,116(2):83-89
JETP Letters - High gradients of electron temperature appear in plasma corona under direct laser irradiation of inertial confinement fusion targets. This results in nonlocality of heat transport.... 相似文献
44.
E. I. Ageev V. Yu. Bychenkov V. P. Veiko A. A. Ionin S. I. Kudryashov A. A. Petrov A. A. Samokhvalov 《JETP Letters》2016,104(6):421-424
Spectral studies of optical emission from plumes produced via ablation of the surface of stainless steel in the phase explosion regime at different incident fluences by a pair of collinear degenerate femtosecond laser pulses, separated by variable delay time of 0.01–1.5 ns, demonstrate a drastic decrease in atomic emission intensities in a subnanosecond range. This effect was related to “bulk” absorption of the second pump pulse in ablative plumes with near-critical density, achieved during their hydrodynamic expansion on a subnanosecond timescale. 相似文献
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We review the recent advances in constructing analytical solutions of self-consistent Vlasov-Poisson equations in plasma. These solutions describe different physical phenomena, such as the ion acceleration in the adiabatic expansion of a plasma bunch and the Coulomb explosion of cluster plasma. The particle distribution function, mean velocity, and density distribution, as well as the energy spectra for accelerated ions, are discussed. 相似文献
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V. Yu. Bychenkov Y. Sentoku S. V. Bulanov K. Mima G. Mourou S. V. Tolokonnikov 《JETP Letters》2001,74(12):586-589
Two-dimensional “particle-in-cell” modeling was carried out to determine the laser intensity threshold for pion production by protons accelerated by the relativistically strong short laser pulses acting on a solid target. The pion production yield was determined as a function of laser intensity. 相似文献
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Half integer (3/2ω0, 1/2ω0) harmonics generation under oblique incidence of the pump-wave on the spatially inhomogeneous plasma is theoretically investigated. Harmonics generation is connected with the two-plasmon convective instability excitation near the quarter-critical density. Harmonics spectra and intensities depend essentially on the pump wave polarization. In particular, significant harmonics spectra broadening arises under the p-polarized pump wave. 相似文献
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By using relativistic massively parallel PIC code MANDOR, which features arbitrary target design including 3D micro‐structuring, a study of ion acceleration in short laser pulse interaction with different thin targets has been performed. Based on 3D simulation results it has been shown that micro‐structures on the front surface of thin plane targets increase a number and energy of hot electrons in comparison with that for the case of pure plain foils of optimal thickness. As a result, the energy of accelerated ions also increases up to 50%. However, the efficiency of ion acceleration from structured target reduces with laser pulse intensity increase, so that for laser pulses of ultra‐relativistic intensity a positive role of surface micro‐structuring diminishes. We have also studied to which extent a sub‐ps imperfection of the laser pulse shape, which smoothes the surface micro‐structures suppresses high‐energy ion generation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
49.
Sarkisov GS Bychenkov VY Novikov VN Tikhonchuk VT Maksimchuk A Chen SY Wagner R Mourou G Umstadter D 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):7042-7054
Using interferometry, we investigate the dynamics of interaction of a relativistically intense 4-TW, 400-fs laser pulse with a He gas jet. We observe a stable plasma channel 1 mm long and less than 30 microm in diameter, with a radial gradient of electron density approximately 5 x 10(22) cm(-4) and with an on-axis electron density approximately ten times less than its maximum value of 8 x 10(19) cm(-3). A high radial velocity of the surrounding gas ionization of approximately 3.8 x 10(8) cm/s has been observed after the channel formation, and it is attributed to the fast ions expelled from the laser channel and propagating radially outward. We developed a kinetic model which describes the plasma channel formation and the subsequent ambient gas excitation and ionization. Comparing the model predictions with the interferometric data, we reconstructed the axial profile of laser channel and on-axis laser intensity. The estimated maximum energy of accelerated ions is about 500 keV, and the total energy of the fast ions is 5% of the laser pulse energy. 相似文献
50.
V. Yu. Bychenkov V. T. Tikhonchuk S. V. Tolokonnikov 《Journal of Experimental and Theoretical Physics》1999,88(6):1137-1142
A technique is suggested for triggering nuclear reactions by accelerating ions with a powerful ultrashort laser pulse in a
plasma. The underlying idea of the suggested compact “reactor” is utilization of high-energy ions accelerated by the charge-separation
electrostatic field in the direction perpendicular to the laser beam axis in a gas-filled capillary. Accelerated ions with
energies of several MeV penetrating the target from the inside surface of a channel give rise to nuclear reactions which can
be used to create a compact source of fast neutrons and neutrons of intermediate energies for generating various (short-and
long-lived, light and heavy) isotopes, for generating gamma radiation over a broad energy range, for making sources of light
ion and induced radioactivity. The yield of the corresponding nuclear reactions as a function of the laser beam parameters
has been investigated. The suggested technique for triggering nuclear reactions provides a practical tool for studies of nuclear
transformation on the pico-and nanosecond scales, which cannot be achieved using other methods.
Zh. éksp. Teor. Fiz. 115, 2080–2090 (June 1999) 相似文献