…
► Since (
29.2.5 ) implies that
cos
ϕ
=
sn
(
z
,
k
)
, (
29.15.1 ) can be rewritten in the
form
…
…
► For large values of the parameters in the
3
j
,
6
j
, and
9
j
symbols, different asymptotic
forms are obtained depending on which parameters are large.
…
►
34.8.1
{
j
1
j
2
j
3
j
2
j
1
l
3
}
=
(
−
1
)
j
1
+
j
2
+
j
3
+
l
3
(
4
π
(
2
j
1
+
1
)
(
2
j
2
+
1
)
(
2
l
3
+
1
)
sin
θ
)
1
2
(
cos
(
(
l
3
+
1
2
)
θ
−
1
4
π
)
+
o
(
1
)
)
,
j
1
,
j
2
,
j
3
≫
l
3
≫
1
,
…
►
34.8.2
cos
θ
=
j
1
(
j
1
+
1
)
+
j
2
(
j
2
+
1
)
−
j
3
(
j
3
+
1
)
2
j
1
(
j
1
+
1
)
j
2
(
j
2
+
1
)
,
…
► Semiclassical (WKBJ) approximations in terms of
trigonometric or exponential functions are given in
Varshalovich et al. (1988 , §§8.9, 9.9, 10.7) .
…
…
► Orthogonality and normalization of eigenfunctions of this
form is respect to the measure
r
2
d
r
sin
θ
d
θ
d
ϕ
.
…
…
► The integral is of the
form of the real part of (
36.12.1 ) with
y
=
ϕ
,
u
=
θ
,
g
=
1
,
k
=
ρ
, and
►
36.13.3
f
(
θ
,
ϕ
)
=
−
cos
(
θ
+
ϕ
)
cos
2
θ
.
…
►
θ
+
(
ϕ
)
=
1
2
(
arcsin
(
3
sin
ϕ
)
−
ϕ
)
,
►
θ
−
(
ϕ
)
=
1
2
(
π
−
ϕ
−
arcsin
(
3
sin
ϕ
)
)
.
…
►
► ►
Figure 36.13.1: Kelvin’s ship wave pattern, computed from the uniform asymptotic approximation (36.13.8 ), as a function of
x
=
ρ
cos
ϕ
,
y
=
ρ
sin
ϕ
.
Magnify
…
…
►
x
=
c
(
ξ
2
+
1
)
(
1
−
η
2
)
cos
ϕ
,
►
y
=
c
(
ξ
2
+
1
)
(
1
−
η
2
)
sin
ϕ
,
…
►
30.14.3
h
ξ
2
=
c
2
(
ξ
2
+
η
2
)
1
+
ξ
2
,
…
► The wave equation (
30.13.7 ), transformed to oblate spheroidal coordinates
(
ξ
,
η
,
ϕ
)
, admits solutions of the
form (
30.13.8 ), where
w
1
satisfies the differential equation
►
30.14.7
d
d
ξ
(
(
1
+
ξ
2
)
d
w
1
d
ξ
)
−
(
λ
+
γ
2
(
1
+
ξ
2
)
−
μ
2
1
+
ξ
2
)
w
1
=
0
,
…
…
►
x
=
c
(
ξ
2
−
1
)
(
1
−
η
2
)
cos
ϕ
,
►
y
=
c
(
ξ
2
−
1
)
(
1
−
η
2
)
sin
ϕ
,
…
►
30.13.9
d
d
ξ
(
(
1
−
ξ
2
)
d
w
1
d
ξ
)
+
(
λ
+
γ
2
(
1
−
ξ
2
)
−
μ
2
1
−
ξ
2
)
w
1
=
0
,
►
30.13.10
d
d
η
(
(
1
−
η
2
)
d
w
2
d
η
)
+
(
λ
+
γ
2
(
1
−
η
2
)
−
μ
2
1
−
η
2
)
w
2
=
0
,
…
►
30.13.12
w
3
(
ϕ
)
=
a
3
cos
(
m
ϕ
)
+
b
3
sin
(
m
ϕ
)
.
…
§33.10 Limiting Forms for Large
ρ
or Large
|
η
|
►
§33.10(i) Large
ρ
…
►
F
ℓ
(
η
,
ρ
)
=
sin
(
θ
ℓ
(
η
,
ρ
)
)
+
o
(
1
)
,
…
►
§33.10(ii) Large Positive
η
…
►
§33.10(iii) Large Negative
η
…