High-principal quantum numbers

Rydberg atoms, atoms in states of high principal quantum number, n, are atoms with exaggerated properties. While they have only been studied intensely since the nineteen seventies, they have played a role in atomic physics since the beginning of quantitative atomic spectroscopy. Their role in the early days of atomic spectroscopy is described by White.1... 

From the early spectroscopic work it is possible to construct an energy level diagram for Na, as shown in Fig. 1.1. From this figure it is apparent that the difference in the principal and sharp series limits is the wavenumber of the 3s-3p transition. It is also apparent that the Rydberg states, states of high principal quantum number n, lie close to the series limit. 

Figure 2. Comparison of the- stepwise excitation results (O) with the model calculation ( ). The enhancement (the two-photon signal divided by the one-photon signal) normalized for laser energy is plotted against the absorption coefficient for the 3p -> nd transitions. For visual clarity a curve is drawn through the points of the model calculation and a dashed line of unit slope is drawn through the data at high principal quantum number, n.

Discussion (a) For high principal quantum numbers (n > 7) ionization is much faster than quenching (see Table I), and so the details of the possible quenching processes are unimportant. Essentially all of the atoms excited to a given nd state are ionized, and the observed signal is simply proportional to the absorption probability of the second step (12) ... 

Exotic atoms are produced by stopping a beam of negatively charged particles like muons, pions, or antiprotons in a target, where they are captured in the Coulomb potential of the atoms at high principal quantum numbers n. These systems deexcite mainly by fast Auger emission of electrons in the upper part of the atomic cascade and more and more by X-radiation for lower-lying states. 

Li), 16956 cm (Na), 12985 cra (K), 12578 cra (Cs)] do not contribute to the thermal functions below 1006 K there is only a translational contribution below this temperature. Above this approximate temperature, the thermal functions become increasingly sensitive to the partition function cutoff procedure used, due to the combined effect of the observation of atomic energy levels of high principal quantum number and a low ionization potential. Energy levels have been observed up to n = 42 (Li), 59(Na), 79(K), 77(Rb), and 73(Cs). However, not all predicted levels have... 

Rydberg series A Rydberg state is a state of an atom or molecule in which one of the electrons has been excited to a high principal quantum number orbital. A Rydberg series is the set of bound states of the excited electron for a given set of excited electron angular momentum quantum numbers and ion core state. 

The next example illustrates how the corresponding atom is chosen. Consider the molecules HI and HBr. The presence of the light H atom results in a very open rotational structure, so that, at high principal quantum numbers, successive Rydberg manifolds overlap. Since separated Rydberg members do not occur at very high n, they can only be sorted out by rotational cooling. 

Since continuity across the threshold is so fundamental, it is worth testing the principle under conditions where / values can be measured to very high principal quantum numbers n, and where a strong intruding resonance located in the photoionisation continuum just above the threshold perturbs the course of intensities in the Rydberg series. An example of this kind occurs in the spectrum of Ba and is shown in fig. 4.3. The fact that, even in such a case, the df/dE curve joins completely smoothly shows that perturbations do not upset this principle, i.e. that it is of very general validity. 

K.D. Heber, RJ. West, E. Matthias, Collisions between Sr-Rydberg atoms and intermediate and high principal quantum number and noble gases. J. Rhys. D 21, 563 (1988)... 

The largest atom is the caesium atom. The reason is a high principal quantum number for the valence orbital, while at the same time, screening is high since all other electrons are located in the inner shells. 

Hypetfine-Induced State Mixing (n-Mixing) at High Principal Quantum Numbers... 

In order to evaluate the oil-diagonal matrix element, the radial overlap integral needs to be calculated. The overlap between the 5s and the Rydberg electron is proportional to n and can hence be neglected at high principal quantum numbers. On this assumption, one obtains... 

In plasma diagnostics, for example. Stark spectroscopy is used for determining the local electric field. Since the Stark splitting is large for the Rydberg levels, the excitation to the level with high principal quantum number n is used. A small amount of probe atoms mixed in the plasma are excited to metastable... 

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