LIGHT EMISSION OBSERVED FROM IONIZING RADIATION SOURCES BY AN ATOMIC PHENOMENON (original) (raw)

ATOMIC EMISSION OF LIGHT FROM SOURCES OF IONIZING RADIATION BY A NEW ATOMIC PHENOMENON

Technical Report: Abstract: Light emission has been observed from all the targets (like Rb, and Ba which are opaque to light during excitation by γ-rays from 241Am), and the radionuclides investigated that can not be explained by the known phenomena. Light emission from metals ( Cu, Mo, and Ag targets; and radionuclides: 57Co and 60Co) at room temperature is a noteworthy observation, that implies the emission from metal atoms. It reveals that sources of ionizing radiation, in general, give rise to atomic emission of light by a new phenomenon. A detailed study showed dominance of ultraviolet(UV) radiation from low energy ionizing radiation sources, while raise towards near-infrared (NIR) radiation from high energy sources. These findings led to believe that ionizing radiation loose energy in eV level while passing through charged space within the atom of their origin. The loss of their energy that forms electromagnetic radiation, with energies in eV level, excites valence electron and causes fluorescent light emission.

Atomic sources controlled by light: main features and applications

16th International School on Quantum Electronics: Laser Physics and Applications, 2010

We present in this paper recent results on Light -Induced Atom Desorption (LIAD) in sealed and open coated cells. LIAD is defined via the description of an experiment on rubidium atoms stored in a dry -film coated cell, where a few milliwatts of even non coherent and non resonant light are able to increase the alkali atomic density for more than one order of magnitude. Modeling of the effect is given. New features become relevant in the case of LIAD in porous glasses: in fact, although the photodesorption efficiency per unit area in bare glass is much lower, photoatomic sources can be prepared, due to the huge inner surface of porous samples. We applied LIAD from organic coatings to the stabilization of alkali densities out of equilibrium: sodium case is here discussed. Finally, we report on fully original, preliminary measurements of rubidium Magneto -Optical Trap loading via LIAD from a dry -film coated cell.

Highly-excited atoms in the electromagnetic field

1983

A review is given of the properties of highly excited atoms placed in an electromagnetic field. The probabilities of bound-bound and bound-free transitions between quasiclassical atomic states, and also approximate selection rules for such transitions, are examined. The properties of the dynamic polarizability of highly excited states of atoms are investigated. Quantum-mechanical ionization mechanisms (multiphoton and tunneling) are discussed for highly excited states. Much space is devoted to the stochastic dynamics of classical atomic electrons in a varying monochromatic electromagnetic field. The threshold electric field for the stochastic motion of an electron and the ionization of an atom is given as a function of the field frequency, its polarization, and the principal quantum number of the atomic state under consideration. The influence of orbital angular momentum of the state from which ionization takes place on the stochastization process is discussed. Classical diffusion ionization of a highly excited atom in an electromagnetic field is considered within the framework of classical mechanics and the quasiclassical quantum-mechanical approximation. The validity of classical mechanics in relation to the properties of highly excited atoms in an electromagnetic field is examined. The realization of quantum and quasiclassical ionization of highly excited atoms is considered. The final part of the review analyzes experimental data on the behavior of highly excited atoms in a radiofrequency field. Comparison of experimental data with the theory given in this review has demonstrated good agreement between them.

Atom optics: Old ideas, current technology, and new results

Annalen der Physik, 2001

Atom optics is the coherent manipulation of the atomic matter waves originally postulated by the developers of quantum mechanics. These pioneers also proposed the use of stimulated light forces to manipulate particles. These ideas have been combined with current technology to produce the field of atom optics. This, in turn, has shed new light on old quantum problems like the which way problem and the origins of quantum decoherence. Bose Einstein condensates combine naturally with atom optics to produce new results such as the coherent amplification of matter waves. This review of atom optics traces these connections.

Absorption and emission of radiation by an atomic oscillator

Phys Essays, 2003

The theory of absorption and emission of electromagnetic radiation by an oscillator consisting of the atomic nucleus and one electrically charged particle is deduced using classical electrodynamics. In the steady state of an atom, emission and absorption of electromagnetic radiation are equal, so the atom is stable. In order to include reactive effects of electromagnetic radiation in the motion equations, the Newton equation is modified by adding the radiative reaction force. This paper is an introduction to the derivation of the basic assumptions of quantum mechanics.

Radiative and dynamical properties of homogeneously prepared atomic samples

Physical review. A, 1988

We have employed an experimental apparatus in which a sample of nearly ideal, two-level atoms can be exposed to homogeneous amplitudeand phase-controlled resonant laser light to study fundamental dynamical, spectral, and radiative atomic properties. In particular, we show unambiguously that atomic 6uorescence is maximized when atoms are purely in their excited state rather than in a superposition of ground and excited state. We also show that fluorescence lifetimes are independent of the atomic excitation level, and finally, we demonstrate interesting correlations between atomic dynamics and atomic spectral features.

Swift heavy ion induced electron emission from solids

Journal of Physics: Conference Series, 2015

This article discusses the effect of atomic aggregation (or molecular effect) in the electron emission of solids by the impact of particles at low velocities (<Fermi velocity). For small molecules, the depression of potential electron emission results from resonance neutralization to deep excited levels in molecules, followed by Auger de-excitation, which competes with the more efficient channel of Auger electron capture. The near "threshold" region in kinetic emission is analyzed and it is suggested that reported thresholds may result from insufficient experimental sensitivity. The molecular effect in kinetic emission is discussed in terms of interference in electron scattering and of cooperative effects due to multiple atomic collisions. The latter effects are evident when slow, large molecules are heated when rebounding from surfaces and in the hot plasma formed during the impact of cosmic dust on solids.