Rir)= ail? Sito) a2. 
sin 0 
Equation 5.101 shows that R(r) has the form of a damping periodic function with period 
2x/o and damping a2. 
From Eq. 5.98’ 
(5.101) 
Gz cos{—a;/2 a3) (5.98”’) 
SO a2 determines the damping and a,/ Vay determines the period (see Fig. 5.18). 
fa) 
Fig. 5.18. A(r) of AR(2);a2 >a?/4. 
As an extreme case of stationality, when a2 = 1, from Eq. 5.1000 = 7/2. 
Therefore from Eq. 5.101 
R(r) = cosra oz. (5.102) 
This is an undamped cosine curve and shows that R(r) does not decay with increasing r 
but continues to oscillate in this case. 
5.2.3.5 Estimation of a\, a2. From Eqs. 5.83 and 5.84 
a,R(0) + a2R(1) = —R(1) 
a,R(1) + a2R(O) = — R(2) 
RQ) R(1) RO) R(1) 
~1R(2) R(O) ~1RQ) R(2) 
Thus Gi =) ay a Gy= a ae ae, (5.103) 
RO) R(1) RO) RQ) 
R(1) RO) R(1) RO) 
or 
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