Feasibility of developing a cw laser with a radionuclide pump source

Abstract

As an extension of the Robinson-Trautman solutions of D = 4 general relativity, we investigate higher dimensional spacetimes which admit a hypersurface orthogonal, non-shearing and expanding geodesic null congruence. Einstein's field equations with an arbitrary cosmological constant and possibly an aligned pure radiation are fully integrated so that the complete family is presented in a closed explicit form. As a distinctive feature of higher dimensions, the transverse spatial part of the general line element must be a Riemannian Einstein space, but it is otherwise arbitrary. On the other hand, the remaining part of the metric is-perhaps surprisingly-not so rich as in the standard D = 4 case, and the corresponding Weyl tensor is necessarily of algebraic type D. While the general family contains (generalized) static Schwarzschild-Kottler-Tangherlini black holes and extensions of the Vaidya metric, there is no analogue of important solutions such as the C-metric.

Simulation of NPL in experiments with e-beam pumping

“…Laser on xenon atom transitions has one of the lowest oscillation thresholds between highpressure gas lasers, and it allows us to obtain lasing pulse durations up to 2.5 ms under electronbeam pumping (Koval' et al 1986;Perkins 1993) and 50 ms under fission fragment excitation (Voinov etal 1991). Such long laser pulse durations are more interesting for reactor lasers, and they also may be useful for industry lasers, where the optimal radiation pulse duration for the same technological processes is about 0.1-1 ms.…”

Nuclear-Induced Plasmas of Gas Mixtures and Nuclear-Pumped Lasers

“…was studied before to create gas scintillators [5,6]. Radioactive isotopes usage for laser pumping [7] or pre-ionization in electric discharge lasers [8,9] is limited by lower power density deposited in gas (up to 0.6 W/cm 3 ). The main volume of works on NPL active media search and study of their parameters was performed on stationary and pulsed nuclear reactors.…”

“…Xenon laser also has the lowest lasing threshold: 1.5°10 12 n/cm 2 s in Ar-Xe mixture (λ = 2.03 µm) [7,68]. These advantages, as well as the absence of degradation of the laser mixture as a result of radiation and chemical reactions, join the lasers operating on IR transitions of Xe, Kr, Ar the ranks of most promising in terms of reactor-laser creation [18].…”

Theoretical feasibility study of new high-efficiency continuous-wave lasers operating at electron transitions in the spectral regions from near ir to uv on the basis of unconventional mechanisms of forming the active gaseous media

“…In order to estimate the power and duration of lasing during the excitation pulse, we used a simple and well validated kinetic model of a copper-vapor laser, which was outlined in [12], with typical values of rate constants for the processes involved. The excitation constant for the metastable state was taken equal to 10 -8 cm3/s and that of the resonance state, equal to ~10 -7 cm3/s; the decay constant for the resonance level with instantaneous ionization was chosen equal to ~10 -6 cm3/s; and the ionization rate from the ground state was taken equal to ~10 -8 cma/s.…”

“…The iodine-oxygen laser with pure chemical excitation (the near-IR region, A = 1.315 pm) occupies an important place here. Unique research and development efforts related to oxygemiodine laser have been headed by Professor V. A. Katulin until recently, and are now in progress at the Samara Branch of the P. N. Lebedev Physical Institute of the Russian and nuclear pumping [12], quasi-continuous lasing is observed. Pulse durations of 1 10 ms were attained.…”