Journal of Physics B Atomic Molecular and Optical Physics

Rates of blackbody radiation-induced transitions from Rydberg states of alkali atoms

Vitalii D Ovsiannikov, Igor L. Glukhov, E A Nekipelov

Published Sep 21, 2011• 29 citations

Abstract

General properties are considered of three different terms in the imaginary part of the Stark effect on n S, n P and n D Rydberg states of alkali atoms in the field of environmental blackbody radiation with temperature in the ranges between T = 100 K and T = 3000 K. The terms are equal to the rates of decay P d nl ( T ), excitation P e nl ( T ) and ionization P ion nl ( T ) and may be separated and determined independently of each other. Corresponding numerical data calculated together with the rates of spontaneous decay P sp nl in the region of principal quantum numbers n from n = 10–1000 are transformed into fractional rates R d(e, ion) nl ( T ) = P d(e, ion) nl ( T )/ P nl sp . The asymptotic dependences on T and n display an essential difference between the fractional rates of ionization R ion nl ( T )∝ Tn 2/3 and the rates of decay (excitation) R d(e) nl ( T )∝ Tn , approximated by two different asymptotic formulae, one for R ion nl ( T ) and another one for R d(e) nl ( T ). The approximation polynomials with coefficients, determined from the curve-fitting polynomial interpolation procedure for three values of n between n = 15 and n = 150 at three values of temperature T = 100, 300, 1000 K, reproduce the calculated values with fractional departures below 2–3% in the regions from n = 10 to n = 1000 at temperatures from T = 100 K to T = 3000 K.

DOI: 10.1088/0953-4075/44/19/195010

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