Nuclear-Pumped Lasers

McDaniel, E.W. Flannery, M.R. Thomas, E.W. Ellis, H.W. McCann, K.T. Manson, S.T. Gallagher, J.W. Rumble, J.R. Beaty, E.C. Roberts, T.G. Compilation of Data Relevant to Nuclear Pumped Lasers, Technical Report H-78-I, US Army Missile Research an Development Command Redstone Arsenal, Alabama, 1979 Vol. 5, p 1917. 

Lasers, Chemical Lasers, Color Center Lasers, Dye Lasers, Free Electron Lasers, Gas Lasers, Nuclear Pumped Lasers, Optical Fiber Lasers, Semiconductor Lasers, Solid State Lasers, Ultrafast Pulse TLchnology Lasers, X-Ray... 

TABLE I Representative Nuclear Pumped Lasers (See attached corrections)... 

The charged particles are sufficiently energetic that excitation of a broad range of atomic and molecular states is energetically allowed. There is also, in general, no mechanism for selective excitation of only a few excited states. This selectivity of excitation, which has fi equently been used to produce laser action, is not generally available in nuclear pumped lasers. 

For laser applications that require a very large laser or a laser remote fi om conventional electrical or chemical power sources, a nuclear pumped laser may be an effective alternative to more conventional lasers. Commercial, power reactors routinely operate for months at total fission powers of3000 MW, with corresponding electrical power... 

Karelin, A. V., et al. (1997). Nuclear-Pumped Lasers and Physical Problems in Constructing a Reactor-Laser, Quantum Electronics 27, 375. 

Magda, E. P. (1998b). Review Powerful Nuclear Pumped Lasers, Proc. SPIE—Int. Soc. Opt. Eng. (USA) 3574,93. 

A qualitatively different approach to probing multiple pathways is to interrogate the reaction intermediates directly, while they are following different pathways on the PES, using femtosecond time-resolved pump-probe spectroscopy [19]. In this case, the pump laser initiates the reaction, while the probe laser measures absorption, excites fluorescence, induces ionization, or creates some other observable that selectively probes each reaction pathway. For example, the ion states produced upon photoionization of a neutral species depend on the Franck-Condon overlap between the nuclear configuration of the neutral and the various ion states available. Photoelectron spectroscopy is a sensitive probe of the structural differences between neutrals and cations. If the structure and energetics of the ion states are well determined and sufficiently diverse in... 

In this section, we describe the motion of vibronic WPs created in a diatomic molecule that has only one vibrational mode. The influence of other degrees of motions such as rotation and nuclear spins are omitted for simplicity. Since our studies deal with the quantum property of the system in which relaxations can be neglected, the decoherence process is not taken into account in the following formulations. Assuming that the molecule occupies a single vibrational level v = 0 as an initial state, the WP generated by the absorption of a pump laser pulse is given as... 

The nuclear function %a(R) is usually expanded in terms of a wave function describing the vibrational motion of the nuclei, and a rotational wave function [36, 37]. Analysis of the vibrational part of the wave function usually assumes that the vibrational motion is harmonic, such that a normal mode analysis can be applied [36, 38]. The breakdown of this approximation leads to vibrational coupling, commonly termed intramolecular vibrational energy redistribution, IVR. The rotational basis is usually taken as the rigid rotor basis [36, 38 -0]. This separation between vibrational and rotational motions neglects centrifugal and Coriolis coupling of rotation and vibration [36, 38—401. Next, we will write the wave packet prepared by the pump laser in terms of the zeroth-order BO basis as... 

The inelastic contributions to the signal are only important for light atoms [30] and, in addition, relatively insensitive to the atomic arrangement [20]. Hence, in a practical experiment where the nuclear dynamics is elucidated by making difference diffraction images one with the pump laser turned on minus one with the pump laser turned off, the inelastic terms can be ignored. 

Lasers Lasers, Color Center Lasers, Gas Lasers, Nuclear Pumped... 

Nuclear device pumped laser (NDPL) Laser pumped by the very high radiation fluxes obtainable near an exploding nuclear device. 

Reactor pumped laser (RPL) Laser pumped by a portion of the leakage neutrons or gamma rays produced by a pulsed or steady-state nuclear reactor. 

Experimental reseach directed toward discovery of new RPLs has continued at the University of Illinois. System studies of possible large-scale RPL applications and detailed measurements of radiation-induced absorption in optical materials have been reported. Concepts for using nuclear-pumped flashlamps for industrial applications and for laser excitation have been explored [Prelas (1995)], and the first nuclear-flashlamp-pumped laser (iodine at 1.31 micron) has been reported. 

However, these apphcations must be realized in the presence of the unique disadvantages of nuclear pumping Low pump power per unit volume (for RPLs, not NDPLs) intense radiation fields extraction of the laser beam from the complex reactor stracture (for substrate pumping) and the health, safety, and proliferation concerns of nuclear technology in general. 

Prelas, M. A. (1995). Lasers with Combined Nuclear Pumping, loser Part. Beams 13,351. 

Seregin, A. A., etal. (1999). Model of a Nuclear Pumped Liquid Laser, Quantum Electronics 29,406. 

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