Neutron resonance spectroscopy. XII. The separated isotopes of W

Journal Article · Thu Nov 01 04:00:00 EST 1973 · Phys. Rev., C, v. 8, no. 5, pp. 1813-1826

DOI:https://doi.org/10.1103/PhysRevC.8.1813· OSTI ID:4313126

Camarda, H S; Liou, H I; Hacken, G; Rahn, F; Makofske, W; Slagowitz, M; Wynchank, S; Rainwater, J

The results of neutron resonance time-of-flight spectroscopy measurements using the Nevis synchrocyclotron are given for the separated W isotopes (182, 184, 186) and for natural W. Almost all s levels were observed to 2.65 keV, and resonance (g) GAMMA /sup o//sub n/ values are presented to ~ 16 keV for thc above even isotopes, and to 700 eV and 2.6 keV, respectively, for / sup 183/W. The /sup 183/W level assignments were fro m levels in natural W which were not assigned to the other isotopes. A Bayes's theorem analysis shows that nearly all of the observed levels are s rather than p levels, since W is at a maximum for the s strength function S/sub o/ but not for Si, and the level detection sensitivity was not sufficient to deteet other than exceptionally strong p levels. We were able to assign J values to 14 s levels of /sup 183/W. The 41 observed /sup 182/W levels to 2.65 keV and the 52 /sup 187/W levels to 701 eV seem to be pure complete s populations, being fitted excellently by the Wigner nearest neighbor spacing theory and the Porter-Thomas reduced neutron width distribution. The orthogonal ensemble (OE) theory was found to be in good agreement with the /sup 182/W and /sup 183/ data. The /sup 184/W level set to ~ 2.6 keV also seems to be an essentially complete, pure, s population sample. While it agreed within statistical limits to the above statistical theories, it gave poorer discrimination against altemate theories. Tests suggested that a few s levels in /sup 186/W had been missed to ~ 2.6 keV. The 10/sup 4/S/sub o/ values are 2.40 plus or minus 0.31, 1.65 plus or minus 0.32, 2.35 plus or minus 0.24, an d 2.23 plus or minus 0.27 for 182, 183, 184, and 186, respectively. The < D> values for s populations are 66.3 plus or minus 3.2 eV (182), 13.2 plus or minus 0.7 eV (183), 81.3 plus or minus 5.1 eV (184), and 90 plus or minus 7 eV (186). A useful and accurate method for evaluating the Doppler-broadening integrals is described. (auth)

• Research Organization: Columbia University, New York, New York 10533
• Sponsoring Organization: USDOE
• NSA Number: NSA-29-022982
• OSTI ID: 4313126
• Journal Information: Phys. Rev., C, v. 8, no. 5, pp. 1813-1826, Journal Name: Phys. Rev., C, v. 8, no. 5, pp. 1813-1826; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

*TUNGSTEN 182-- ENERGY LEVELS
*TUNGSTEN 183-- ENERGY LEVELS
*TUNGSTEN 184-- ENERGY LEVELS
*TUNGSTEN 186-- ENERGY LEVELS
CROSS SECTIONS
LEVEL WIDTHS
N68831* --Physics (Nuclear
Experimental)--Nuclear Properties &amp; Reactions
150 &lt;= A &lt;= 189--Energy Levels &amp; Transitions
NEUTRON SPECTROSCOPY
RESONANCE NEUTRONS
S STATES
STRENGTH FUNCTIONS