VARIABLE STARS
189
/
3£i + £o£i' — 0 and will probably fall within the boundary; the wave is
thus a little too short to fit the star. We lengthen it by diminishing oj 2 .
On trying a> 2 = ‘055 we see that we have greatly overshot the mark;
£i" is (as far as we trace it) increasing more and more rapidly and the
wave is quite out of control. Taking co 2 = -065 we find that the wave is
much too short and there will be a node well within the star. The results
show that the solution is very sensitive to small changes of oj 2 so that the
true solution cannot be far from to 2 = -060.
Table 26.
Trial Solutions for a Pulsating Star (a = 0-2).
oj 2 = -055
co 2 = -069
w 2 = , 065
= 0
Si
Si
£i"
ii
&
Si"
Si
Si
Si"
0
1
0
•0423
1
0
•0413
1
0
•0403
1
1-0218
•0443
•0504
10212
•0431
•0476
1-0206
•0420
•0448
li
1-0345
•0573
•0538
1-0335
•0554
•0506
1-0325
•0535
•0474
H
1-0505
•0713
•0585
1-0489
•0685
•0541
1-0474
•0657
•0497
ii
1-0702
•0867
•0644
1-0678
•0825
•0584
1-0654
•0784
•0524
2
1-0940
•1037
•0718
1-0903
•0977
•0634
1-0867
•0919
•0550
2J
1-1223
•1227
•0806
1-1168
•1142
•0688
11114
•1059
•0570
H
1-1556
•1441
•0912
1-1475
•1320
•0744
1T396
•1202
•0577
2|
1-1946
•1685
•1041
1-1829
•1514
•0804
1T715
•1346
•0568
3
1-2401
•1965
•1203
1-2234
•1723
•0862
1-2069
•1484
•0529
3i
1-2932
•2290
•1407
1-2692
•1945
•0917
1-2456
•1606
•0440
H
1-3551
•2672
•1676
1-3208
•2181
•0968
1-2870
•1697
•0276
H
1-4272
•3135
•2045
1-3784
•2427
•0999
1-3300
•1735
-•0014
4
1-5122
•3707
•2571
1-4422
•2678
•0994
—
—
—
4i
1-6131
•4442
•3361
1-5122
•2919
•0927
—
—
—
4*
1-7349
•5427
•4621
1-5879
•3130
•0735
—
—
—
4£
—
—
—
1-6680
•3266
•0289
—
—
—
5
—
—
—
1-7497
•3233
-•0680
—
—
—
It will be shown later that the adiabatic approximation breaks down
near the boundary so that it would not be possible to introduce exact
boundary conditions. But this does not much matter. So long as the node
falls well inside the star (where the approximation is valid) we have to go
on lengthening the wave; and when we have lengthened it a little too
much the solution changes in such a way that no node can possibly occur.
It is found that the value of oj 2 for the fundamental oscillation is
roughly proportional to a. The following results have been found:
a -- 0*1,
CU 2 = ‘0315
a = 0-2,
oj 2 = -060,
ZO
©
II
to 2 = -156.