100
M. Yamanaka
Fig. 4.4 Parameters
obtained by the Rossi-α
method in PNS experiments
by varying subcriticality
(Ref. [12])
(a) Prompt neutron decay constant α
(b) Intensity of uncorrelated probability B
(c) Intensity of correlated probability C
1
2
3
4
5
6
7
8
9
10 11
0.5
1.0
1.5
2.0
2.5
[x10
3
]
Prompt neutron decay constant [1/s]
Subcriticality [$]
Optical fiber
BF 3
21 fuel rods
19 fuel rods
25 fuel rods
1
2
3
4
5
6
7
8
9
10 11
10
3
10
4
10
5
10
6
Intensity of constant term
B in Eq. (3)
Subcriticality [$]
Optical fiber
BF 3
19 fuel rods
21 fuel rods
25 fuel rods
1
2
3
4
5
6
7
8
9 10 11
0
1
2
3
4
19 fuel rods
21 fuel rods
Subcriticality [$]
Correrated intensity
C
Optical fiber
BF 3
25 fuel rods
[x10
5
]