MAGNETIC PAIR SPECTROMETER STUDIES OF ELECTROMAGNETIC TRANSITIONS IN Be$sup 10$ AND B$sup 1$$sup 0$

Journal Article · Tue Oct 15 04:00:00 EDT 1963 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

OSTI ID:4637973

Warburton, E K; Alburger, D E; Wilkinson, D H

An intermediate-image pair spectrometer was used to study electromagnetic transitions in Be/sup 10/ and B/sup 10/. Energy levels in these nuclei were populated by means of the uteron energies between 2.0 and 3.2 Mev. In Be/sup 10/ the branching ratios of the 5.96 yields 0 and 5.96 yields 3.37transitions were determined to be 48 plus or minus 2% and 52 plus or minus 2%, respectively. A pair line corresponding to the 6.26 yields 3.37 transition was observed and an upper limit of 0.4% was placed on the relative intensity of the 6.26 yields 0 transition which supports an assignment of 2/sup -/ for the Be/sup 10/ 6.26-Mev level. In addition, a 6.18 yields 0 transition was observed but not a 6.18 -3.37 transition. The energy difference between the 6.18 yields 0 pair line and the 5.96 -- 0 pair line was measured with sufficient accuracy to show that the Be/sup 10/ 6.18-Mev level has a mean lifetime greater than 5 x 10/sup -13/ sec, and consequently has a most probable spin-parity assignment of 0/sup +/. In B/sup 10/ the relative intensities of the 3.58 yields 0.72 and 3.58 yields 0 transitions were found to be (4.2 plus or minus 0.3): 1 if both transitions are Ml while the branching ratios of the 5.16 yields 2.15, 5.16 yields 0.72, and 5.16 yields 0 transitions were found to be (65 plus or minus 2)%, (29.5 plus or minus 2)%, and (5.5 plus or minus 0.7)%, respectively. Transitions from the B/sup 10/ 4.77-Mev level were not observed and a limit of GAMMA /sub gamma // GAMMA < 0.05 was set for this alpha - particle unbound level. Data are presented to enable GAMMA /sub gamma // GAMMA for the 5.16-Mev level of B/sup 10/ computed when the relative production cross sections of that state and the 3.37-Mev state of Be/sup 10/ in deuteron bombardments become known. In order to obtain these results, calculations of the spectrometer pairline efficiency were extended to include the emission of internal pairs from aligned nuclei. The experimental results are compared to the predictions of the independentparticle model. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• NSA Number: NSA-17-040106
• OSTI ID: 4637973
• Report Number(s): BNL-7044; 0031-899X
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 132; ISSN PHRVA
• Country of Publication: United States
• Language: English

Related Subjects

ALPHA PARTICLES
BERYLLIUM 10
BERYLLIUM 9
BORON 10
BRANCHING RATIO
CROSS SECTIONS
DECAY
DEUTERON BEAMS
EFFICIENCY
ENERGY
ENERGY LEVELS
INDEPENDENT PARTICLE MODEL
LIFETIME
MAGNETIC FIELDS
MEASURED VALUES
MEV RANGE
NEUTRONS
NUCLEAR MODELS
NUCLEAR REACTIONS
NUMERICALS
PARITY
PHYSICS
PRODUCTION
PROTONS
SPECTROMETERS
SPIN
TRANSIENTS