Document Details
PURL
Title:
THE NEUTRON CAPTURE CROSS SECTIONS OF NEPTUNIUM 239
Author(s):
Subject Terms:
IsotopesNEPTUNIUM ISOTOPESNEUTRON ACTIVIATION CROSS SECTIONSNEUTRON CAPTURE CROSS SECTIONNP-239NP-240
Document Location:
DOE Public Reading Room - Hanford Battelle P.O. Box 999 MS H2-53 Richland WA 99352 (509)372-7443
Document Type:
REPORT
Publication Date:
1955 Oct 27
Declassification Date:
1981 Jul 08
Declassification Status:
Declassified
Document Pages:
24
Accession Number:
RL-1-362788
Document Number(s):
HW-39649
Originating Research Org.:
GE - HAPO
OpenNet Entry Date:
2004 Feb 24
OpenNet Modified Date:
2015 Aug 14
Description/Abstract:
CAPTURE CROSS SECTIONS OF NP-239 WERE DETECTED DIRECTLY BY THE COUNTING OF NP-240 FORMED THROUGH NP-239 IRRADIATION. EXAMINATION OF THE GAMMA RAYS FROM NP-240 DECAY SHOWS THE PRESENCE OF 2 ISOMETIC NP-240 NUCLEI WITH HALF LIVES OF 7.3 AND 60 MINUTES. VALUES OF THEIR FORMATION CROSS SECTIONS VAIA THE REACTION NP239 (N, GAMMA) NP-240 ARE 26 AND 15 X 10 TO THE 24TH POWER CM TO THE 2ND POWER, RESPECTIVELY, FOR PILE NEUTRONS. ACCURACY OF THESE VALUES DEPENDS UPON THE DECAY SCHEMES ASSUMED FOR THE ISOMER, AND UPON MORE POSITIVE IDENTIFICATION OF THE 1-HOUR ISOMERS. THE TOTAL ACTIVATION CROSS SECTION OF NP-239 FOR PILE NEUTRONS IS 40 + 16 - 7 X 1- TO THE 24TH POWER CMTO THE 2ND POWER, WHICH INCREASES TO 46 + 18 - 8 X 10 TO THE 24TH POWER CM TO THE 2ND POWER FOR THEMAL NEUTRONS. IN A SECONDARY STUDY, NO GENETIC RELATIONSHIP BETWEEN THE ISOMERS WAS FOUND.