Atomic beam magnetic resonance apparatus

Fig.7.5. Atomic-beam magnetic-resonance apparatus (flop-in arrangement)... 

Fig.18.10. Atomic beam magnetic resonance apparatus. The broken curves in the B magnet show the paths of atoms which have undergone a magnetic dipole transition in the field of the C magnet due to the influence of the applied r.f. field.

Flguic 1. Apparatus for atomic beam magnetic resonance. 

Figure 10.16 shows a block diagram of the whole apparatus, used by PEN-SELIN and his group for atomic beam magnetic resonance spectroscopy detected by laser-induced fluorescence [10.27e]. The pump laser beam crosses the atomic beam several times to assure high pumping efficiency. The rf tran-... 

Fig. 1. Schematic diagram of a triple resonance atomic beam apparatus. Between source S (a hot oven) and detector D, magnets A and B produce inhomogeneous deflecting fields, and act as polarizer and analyzer magnet C produces a homogeneous field in which magnetic resonance transitions occur at loops A, B and C. Resonance is detected by the deflection of atoms away from the detector D, if the gradients in magnets A and B are in opposite directions.

These atoms will not be refocussed at the detector in this so-called flop-out arrangement of the polarizer and analyser fields. Consequently when the detector current is recorded as a function of oJq for a fixed value of B, a series of sharply defined minima will be observed. The width of these magnetic resonance lines is often as narrow as 300 Hz and permits very precise measurements of the spins and magnetic moments of both atoms and nuclei. We shall now discuss some aspects of the atomic beam apparatus in more detail before considering the application of this technique to hyperfine structure measurements in one-electron atoms. 

---