Anomalies in radiation-collisional kinetics of Rydberg atoms induced by the effects of dynamical chaos and the double Stark resonance

摘要

Radiative and collisional constants of excited atoms contain the matrixelements of the dipole transitions and when they are blocked one can expectoccurring a number of interesting phenomena in radiation-collisional kinetics.In recent astrophysical studies of IR emission spectra it was revealed a gap inthe radiation emitted by Rydberg atoms ($RA$) with values of the principalquantum number of $n\approx10$. Under the presence of external electric fieldsa rearrangement of $RA$ emission spectra is possible to associate withmanifestations of the Stark effect. The threshold for electric field ionizationof $RA$ is $E\approx3\cdot10^{4}$ V/cm for states with $n>10$. This means thatthe emission of $RA$ with $n\ge10$ is effectively blocked for such fields. Inthe region of lower electric field intensities the double Stark resonance (orF\"{o}rster resonance) becomes a key player. On this basis it is establishedthe fact that the static magnetic or electric fields may strongly affect theradiative constants of optical transitions in the vicinity of the F\"{o}sterresonance resulting, for instance, in an order of magnitude reduction of theintensity in some lines. Then, it is shown in this work that in the atmospheresof celestial objects lifetimes of comparatively long-lived $RA$ states andintensities of corresponding radiative transitions can be associated with theeffects of dynamic chaos via collisional ionization. The F\"{o}ster resonanceallows us to manipulate the random walk of the Rydberg electron ($RE$) in themanifold of quantum levels and hence change the excitation energies of $RA$,which lead to anomalies in the IR spectra.