Single-Photon Atomic Cooling - Raizen Lab - The University of ...

to the experimental sequence in Ch. 3. Table 2.1 summarizes the physical
properties discussed here. A more complete tabulation and discussion of these
properties is organized in an excellent reference [43].
Atomic Number Z 37
Total Nucleons Z + N 87
Relative Natural Abundance η( 87 Rb) 27.83(2)%
Atomic Mass m 1.443 160 648(72) × 10 −25 kg
Nuclear Spin I 3/2
Table 2.1: 87 Rb Physical Properties
2.2 Fine and Hyperfine Structure
This section reviews interactions leading to a splitting in atomic energy
levels. First the fine structure is explored, followed by a discussion of the
hyperfine structure in rubidium.
2.2.1 Fine Structure
The primary source of energy level splittings in atoms are the elec-
trostatic attraction between the electrons and nucleus and the electrostatic
repulsion between the individual electrons. The energy levels resultant from
these interactions are known as the Bohr energy levels. The next most im-
portant contribution to energy level splittings in low Z atoms are a result of
relativistic effects. These effects are the source of the fine structure of atomic
spectra. The fine structure energy level splittings are smaller than the Bohr
energy level splittings by a factor of ∼ α 2 . Here α denotes the fine structure
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