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References - Bogoliubov Laboratory of Theoretical Physics - JINR

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The energies <strong>of</strong> the states Ψ1 − Ψ6 are<br />

W1 = ΔW<br />

6<br />

− μJ B<br />

2<br />

μJB − μhB, W3 = ΔW<br />

ΔW<br />

6<br />

ΔW<br />

2<br />

B − μJ<br />

2<br />

− ΔW<br />

2<br />

6<br />

+ ΔW<br />

2<br />

+ μJ B<br />

2<br />

�<br />

1+ 2<br />

+ ΔW<br />

2<br />

3 x + x2 , W2 = − ΔW<br />

�<br />

1+ 2<br />

3x + x2 , W5 = ΔW<br />

6<br />

�<br />

1 − 2<br />

3 x + x2 , W6 = − ΔW<br />

3 + μJB + μhB.<br />

3 −<br />

�<br />

1 − 2<br />

3x + x2 , W4 =<br />

B + μJ 2 −<br />

2 The Schroedinger equation in<br />

the uncoupled state basis<br />

W/ W<br />

2.5<br />

2<br />

1.5<br />

1<br />

0.5<br />

0<br />

-0.5<br />

-1<br />

-1.5<br />

-2<br />

-2.5<br />

1<br />

2<br />

3<br />

4<br />

5<br />

0 0.5 1 1.5 2<br />

B/Bc<br />

Figure 1: The scheme <strong>of</strong><br />

3 He 2 3 S1 hyperfine structure<br />

and Zeeman splitting, Bc =<br />

0.2407 T.<br />

The adiabatic transitions for the hyperfine states <strong>of</strong> hydrogen<br />

were considered by Antishev and Belov [1]. Oh [2] published detailed results for the<br />

weak field transitions (WFT) in deuterium. Here we solve this problem for 3 He in the<br />

metastable state 2 3 S1.<br />

In the uncoupled |mh,mJ > state basis<br />

Ψ(t) =C1(t)ψ +<br />

h ψ+<br />

+<br />

J +C2(t)ψ h ψ0 +<br />

J +C3(t)ψ h ψ−<br />

J<br />

+C4(t)ψ −<br />

and we obtain the following equations for the amplitudes:<br />

h ψ+<br />

−<br />

J +C5(t)ψh ψ0 −<br />

J +C6(t)ψh ψ−<br />

J<br />

6<br />

, (2)<br />

dC1/dt = −i/�{C1[−(μh + μJ)Bz +ΔW/3] − C2μJBx/ √ 2 − C4μhBx}<br />

dC2/dt = −i/�{−C1μJBx/ √ 2 − C2μhBz − C3μJBx/ √ √<br />

2+C4 2ΔW/3 − C5μhBx}.<br />

dC3/dt = −i/�{−C2μJBx/ √ √<br />

2+C3[(−μh+μJ)Bz−ΔW/3]+C5 2ΔW/3−C6μhBx}. (3)<br />

√<br />

dC4/dt = −i/�{−C1μhBx + C2 2ΔW/3+C4[(μh − μJ)Bz − ΔW/3] − C5μJBx/ √ 2}.<br />

√<br />

dC5/dt = −i/�{−C2μhBx + C3 2ΔW/3 − C4μJBx/ √ 2+C5μhBz − C6μJBx/ √ 2}.<br />

dC6/dt = −i/�{−C3μhBx − C5μJBx/ √ 2+C6[(μh + μJ)Bz +ΔW/3]}.<br />

3 The Schroedinger equation in the basis <strong>of</strong> the stationary<br />

states<br />

Another way is to solve the Schroedinger equation in the basis <strong>of</strong> the stationary states,<br />

as it was made by Beijers [3] for hydrogen. But he used the ”static” Hamiltonian slowly<br />

changing with time because atoms move through a changing magnetic field. Hasuyama<br />

and Wakuta [4] used the ”static” Hamiltonian for strong field transitions in deuterium.<br />

This approach is not always correct.<br />

We use, as the basis, the stationary states existing at the value <strong>of</strong> the magnetic field,<br />

Bz = B0, at the enter into the region <strong>of</strong> a RF field.<br />

For WFT 2–6 we consider only the four-level system <strong>of</strong> 2,4,5 and 6 substates <strong>of</strong> the<br />

F =3/2 state, since the levels <strong>of</strong> the F =1/2 state are sufficiently distant as to have no<br />

significant effect in our problem. For the amplitudes <strong>of</strong> these states, we use the notations<br />

c2 − c6.<br />

420

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