ENTRY 14666 20201207 14761466600000001
SUBENT 14666001 20201207 14761466600100001
BIB 12 34 1466600100002
TITLE A Measurement of Fission Cross-Sections by the Use of 1466600100003
a Coincidence Proportional Counter 1466600100004
AUTHOR (A.O.Hanson) 1466600100005
REFERENCE (R,CF-618,1943) 1466600100006
REL-REF (I,,J.M.Blair+,R,CF-617,1943) The construction and 1466600100007
operation of proportional counter. 1466600100008
INSTITUTE (1USAWIS) 1466600100009
FACILITY (ACCEL,1USAWIS) 1466600100010
INC-SOURCE (P-LI7) 1466600100011
DETECTOR (PROPC,FISCH) The c-p (coincidence-proportional) 1466600100012
counter and alternately the fission chamber was 1466600100013
placed in front of the target so that the face of the 1466600100014
paraffin radiator and the center of the fission 1466600100015
chamber was at the same definite distance in front of 1466600100016
the target chamber. 1466600100017
SAMPLE The factor 3.5 is the average ratio of the mass of 28 1466600100018
to the mass of 25 in the Mg-XVII-B-6 samples. 1466600100019
METHOD (REC,COINC) Measurement of the 25 and 28 cross- 1466600100020
sections were made using the neutrons from the 1466600100021
Li(p,n) reaction. The determination of the neutron 1466600100022
flux through the samples was made by the use of a 1466600100023
coincidence-proportional counter for measuring the 1466600100024
number of proton recoils from thin paraffin films of 1466600100025
accurately known weights. Three different runs were 1466600100026
made at different times with c-p data taken between 1466600100027
them. The first run was taken with the Mg-XVI-B-7 and 1466600100028
the Mg-C-3 samples, the second with Mg-XVII-B-5 and 1466600100029
Mg-XVII-B-6, and the third with Mg-XVII-B-6 and 1466600100030
Al-XIV-4. 1466600100031
CORRECTION Approximate corrections have been made for the 1466600100032
effective solid angle of the recoil counter and for 1466600100033
the reduction of fission counts due to absorption in 1466600100034
the samples. 1466600100035
HISTORY (20201207C) BP 1466600100036
ENDBIB 34 0 1466600100037
NOCOMMON 0 0 1466600100038
ENDSUBENT 37 0 1466600199999
SUBENT 14666002 20201207 14761466600200001
BIB 3 5 1466600200002
REACTION (92-U-235(N,F),,SIG) 1466600200003
COMMENT Author's summary: It is seen that the 235U 1466600200004
cross section is essentially constant for neutron 1466600200005
energies above 0.5 MeV and has a value of 1.66 b. 1466600200006
STATUS (CURVE) page 11. 1466600200007
ENDBIB 5 0 1466600200008
NOCOMMON 0 0 1466600200009
DATA 2 23 1466600200010
EN DATA 1466600200011
MEV B 1466600200012
0.122 3.179 1466600200013
0.165 2.892 1466600200014
0.227 2.515 1466600200015
0.243 2.349 1466600200016
0.293 2.169 1466600200017
0.313 2.107 1466600200018
0.379 1.707 1466600200019
0.478 1.492 1466600200020
0.481 1.232 1466600200021
0.543 1.650 1466600200022
0.543 1.484 1466600200023
0.690 1.755 1466600200024
0.691 1.611 1466600200025
0.814 1.694 1466600200026
0.814 1.460 1466600200027
0.932 1.830 1466600200028
0.932 1.699 1466600200029
1.105 1.706 1466600200030
1.226 1.545 1466600200031
1.229 1.478 1466600200032
1.385 1.704 1466600200033
1.708 1.595 1466600200034
1.798 1.501 1466600200035
ENDDATA 25 0 1466600200036
ENDSUBENT 35 0 1466600299999
SUBENT 14666003 20201207 14761466600300001
BIB 3 4 1466600300002
REACTION (92-U-238(N,F),,SIG) 1466600300003
COMMENT Author's summary: The 238U cross section rises from 1466600300004
zero at 1 MeV to 0.45 b at 1.8 MeV. 1466600300005
STATUS (CURVE) page 11. 1466600300006
ENDBIB 4 0 1466600300007
NOCOMMON 0 0 1466600300008
DATA 2 6 1466600300009
EN DATA 1466600300010
MEV B 1466600300011
1.105 0.010 1466600300012
1.239 0.044 1466600300013
1.418 0.149 1466600300014
1.544 0.374 1466600300015
1.699 0.423 1466600300016
1.797 0.439 1466600300017
ENDDATA 8 0 1466600300018
ENDSUBENT 17 0 1466600399999
ENDENTRY 3 0 1466699999999