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Outline. IntroductionImportant definitionsThe method of the spin HamiltonianExperimental Methods. Introduction. Nucleus properties:Nuclear spin, INuclear magnetic dipole moment, ?INuclear electric quadrupole moment, QMeasurement of Spin, counting the discrete 2I 1 degenerate statesMeasuremen
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1. Measurement of Spins of Ground States of Radioactive Nuclei Wang, Quan (??)
2. Outline Introduction
Important definitions
The method of the spin Hamiltonian
Experimental Methods
3. Introduction Nucleus properties:
Nuclear spin, I
Nuclear magnetic dipole moment, I
Nuclear electric quadrupole moment, Q
Measurement of Spin, counting the discrete 2I+1 degenerate states
Measurement of I, interaction with external or internal magnetic field
No direct measurement of Q
4. Important definitions Nuclear Spin I
An integer or half integer denoted by I
2I+1 is the spatial degeneracy of the state
Ih is the angular momentum operator
Z-component, Iz, is quantized to the 2I+1values (I, I-1, I-2,, -I)
The magnitude of vector I is
The largest measured being twelve, the largest inferred is eighteen
5. Important definitions Nuclear Magnetic Dipole Moment
6. Important definitions Nuclear Quadrupole Moment
Nuclear Magnetic Octupole And Higher Moments
7. Important definitions Hyperfine Structure Anomaly
For two isotopes of the same element, a, the magnetic hyperfine constant, is proportional to the nuclear g-factor.
In practice,
8. The method of the spin Hamiltonian Determinations are based on the radio-frequency of paramagnetic atoms in atomic beams and of paramagnetic ions in crystalline fields.
Breit-Rabi Hamiltonian:
9. The method of the spin Hamiltonian The system has a total spatial degeneracy of (2I+1)(2J+1).
Last two terms represent the direct interaction of the nuclear and electronic magnetic moments with the external magnetic field.
If B vanishes, the first two terms only partially remove the degeneracy.
10. The method of the spin Hamiltonian Total angular moment
Energy of these states (no B field),
11. The method of the spin Hamiltonian Energy with B field (Week B field),
Energy with B field (Strong B field),
12. The method of the spin Hamiltonian Na23 fine & hyperfine structure Fine structure, Hyperfine,