NUCLEAR RESONANT ABSORPTION OF GAMMA RAYS BY Ca$sup 4$$sup 0$

Journal Article · Fri Dec 01 04:00:00 EST 1961 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.124.1541· OSTI ID:4803199

Eckert, A C; Shrader, E F

Ground-state gamma rays (E gamma = 10.3 Mev) emitted by excited Ca/sup 40/ formed in the reaction K/sup 39/(p, gamma )Ca/sup 40/ at E= 2.05 Mev were resonantly absorbed in calcium. Nuclear resonant absorption occurs when the absorber is placed at such an angle that the energy discrepancy upon emission and absorption of the gamma rays is restored by the Doppler shift resulting from the recoil velocity of the excited Ca/sup 40/ nucleus. The gamma radiation is detected by a scintillation detector mounted behind an angle-defining collimator. The nuclear resonant absorption curve is obtained by observing the transmission through the absorber as the collimator is rotated through the resonant angle. The observed width, which is of the order of 0.8 degree, is a function of the angular divergence of the proton beam and the angular opening of the collimator. From the irtegral of the absorption as a function of angle and from a yield measurement, the radiation width for a transition to the ground state is determined to be 3.6 plus or minus 0.24 ev, while 5.8 plus or minus l.8 ev is found for the proton width, and 10.3 plus or minus 1.7 ev for the total width. These values together with the measured angular distribution of the ground-state radiation are consistent with a 2/sup +/ assignment to this level. (auth)

• Research Organization: Case Inst. of Tech., Cleveland
• NSA Number: NSA-16-007096
• OSTI ID: 4803199
• Journal Information: Physical Review (U.S.) Superseded in part by Phys.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 D, Journal Name: Physical Review (U.S.) Superseded in part by Phys.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: 124; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ABSORPTION
ANGULAR DISTRIBUTION
CALCIUM 40
CONFIGURATION
CROSS SECTIONS
DOPPLER EFFECT
EMISSION
ENERGY LEVELS
GAMMA RADIATION
LIFETIME
MEASURED VALUES
NEUTRONS
NUCLEAR REACTIONS
OPTICAL SYSTEMS
PARITY
PHYSICS
POTASSIUM 39
PROTON BEAMS
RECOILS
RESONANCE
ROTATION
SCATTERING
SCINTILLATION COUNTERS
SPECTRAL SHIFT
SPIN
TRANSPORT
VELOCITY