Excited States in 53Mn by the 53Cr(p,nγ)53Mn Reaction

The properties of the low-lying excited states in 53Mn were studied by measuring γ-ray angular distributions and lifetimes using the 53Cr(p,nγ)53Mn reaction. Energy levels of 53Mn have been found at 0.378, 1.288, 1.440, 1.619, 2.272, 2.405, 2.572, 2.670, 2.687, 2.705, 2.872, 2.876, 2.914, 2.947, 3.005, 3.095, 3.125, 3.183, 3.193, and 3.250 MeV. The measurement of γ-ray angular distributions and yield curves together with predictions based on the compound nuclear statistical model have enabled spin assignments to be made to the following excited states in 53Mn: 1.440 MeV (11/2), 1.619 MeV (9/2), 2.572 MeV (7/2), 2.687 MeV (7/2), 2.947 MeV (9/2), 3.005 MeV (5/2). Multipole mixing ratios and branching ratios were determined for some of the observed transitions. Lifetimes of nine excited states in 53Mn have been measured using the Doppler-shift attenuation method.

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The 12 C(γ, 3α) reaction energy levels of 8 Be and 12 C

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1955.0054 ◽

1955 ◽

Vol 228 (1174) ◽

pp. 376-396 ◽

Cited By ~ 15

Keyword(s):

Ground State ◽

Energy Levels ◽

Electric Quadrupole ◽

Angular Distributions ◽

Reaction Energy ◽

Reaction Proceeds ◽

Γ Ray ◽

Relationship Of ◽

The Relationship ◽

Α Particles

The mechanism of the 12 C(γ, 3α) reaction, for γ-ray energies, E γ , up to about 40 MeV, has been determined from a study of over 2500 stars in nuclear emulsions. The study includes investigation of the angular distributions and correlations of the α-particles. The reaction is initiated mainly by electric-dipole and electric-quadrupole γ-ray interaction, the former being unexpectedly strong when E γ < 20 MeV. For E γ < 25 MeV the reaction proceeds mainly by transitions to the ground-state of 8 Be (spin J = 0), and to 2⋅95 ± 0⋅10 MeV ( J = 2) and 4⋅0 ± 0⋅1 MeV ( J = 2 or 4) levels of 8 Be. Transitions to levels near 6, 10 and 15 MeV (all J = 0, 2 or 4) become predominant when 25 MeV ≤ E γ <26 MeV. For E γ ≥ 26 MeV, most transitions lead to 16⋅8 ± 0⋅2 MeV ( J = 2) and 17⋅6 ± 0⋅2 MeV ( J = 2, possibly 0) levels, and possibly to a further 16⋅4 ± 0⋅2 MeV ( J = 0 or 2) level, levels which have not been detected in other reactions. The reaction mechanism is interpreted in terms of competing modes of decay of a compound nucleus, demonstrating the strong influence of the isotopic spins ( T ) of the levels of 12 C and 8 Be involved. For example, the 2 + levels of 12 C involved when 16 MeV ≤ E γ <20 MeV are (unexpectedly) found to have T = 1, and the 16⋅8 and 17⋅6 MeV levels of 8 Be are also found to have T = 1. The relationship of the 12 C (γ, 3α) reaction to other 12 C photodisintegration reactions (including some new reactions established during the present experiments) is discussed.

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LIFETIME MEASUREMENTS OF EXCITED STATES IN 73As

International Journal of Modern Physics E ◽

10.1142/s0218301304002569 ◽

2004 ◽

Vol 13 (05) ◽

pp. 1019-1034 ◽

Cited By ~ 2

Author(s):

K. P. SINGH ◽

T. KAKAVAND ◽

M. HAJIVALIEI

Keyword(s):

Statistical Theory ◽

Excited States ◽

Doppler Shift ◽

Nuclear Reactions ◽

Angular Distributions ◽

Excitation Energies ◽

Lifetime Measurements ◽

Mixing Ratios ◽

Doppler Shift Attenuation ◽

First Time

The excited states of 73 As have been investigated via the 73 Ge ( p , n γ)73 As reaction with proton beam energies from 2.5–4.3 MeV. The lifetimes of the levels at 769.6, 860.5, 1177.8, 1188.7, 1274.9, 1344.1, 1557.1 and 1975.2 keV excitation energies have been measured for the first time using the Doppler shift attenuation method. The angular distributions have been used to assign the spins and the multipole mixing ratios using statistical theory for compound nuclear reactions. The ambiguity in the spin values for the various levels has been removed. The multipole mixing ratios for eight γ-transitions have been newly measured.

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The 23Na(α,γ)27Al reaction. A survey of the reaction and some properties of the 27Al nucleus

Canadian Journal of Physics ◽

10.1139/p69-198 ◽

1969 ◽

Vol 47 (15) ◽

pp. 1545-1555 ◽

Cited By ~ 11

Author(s):

H. Röpke ◽

N. Anyas-Weiss

Keyword(s):

Excitation Energy ◽

Excited States ◽

Bound States ◽

Branching Ratios ◽

Angular Distributions ◽

Particle Capture ◽

Excitation Energies ◽

Decay Modes ◽

Γ Ray ◽

27Al Reaction

The 23Na(α,γ) reaction has been studied in the region Eα = 2–3 MeV. The γ-ray spectra from a total of 16 resonances have been surveyed using a 40 cm3 Ge(Li) detector. Excitation energies, γ-ray decay modes, branching ratios, and γ-ray yields of these resonances are given. Below Eα = 2.7 MeV, all resonances have [Formula: see text] and the α-particle capture proceeds with [Formula: see text]. The resonances at Eα = 2.696 and 2.797 MeV have strong branches to the Jπ = 11/2+ state in 27Al at 4.509 MeV excitation energy. A measurement of γ-ray angular distributions at these resonances yields Jπ(2.969 res.) = 9/2+, 11/2 and Jπ(2.797 res.) = 9/2+ for the resonances, and Jπ(5.671) = 9/2+, 7/2 and Jπ(4.580) = 9/2+, 7/2 for bound states in 27Al. Investigation of this latter level at the Ep = 2.114 MeV resonance in the 26Mg(p,γ)27Al reaction restricts the spin to 7/2. New excited states in 27Al were found at Ex = 5.504, 5.671, and 7.815 MeV. A state at Ex = 5.499 MeV was confirmed.

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High-Spin States in 23Na

Canadian Journal of Physics ◽

10.1139/p73-154 ◽

1973 ◽

Vol 51 (11) ◽

pp. 1155-1169 ◽

Cited By ~ 37

Author(s):

G. G. Frank ◽

R. V. Elliott ◽

R. H. Spear ◽

J. A. Kuehner

Keyword(s):

Ground State ◽

Branching Ratios ◽

Angular Distributions ◽

Spin States ◽

High Spin States ◽

Doppler Shift Attenuation ◽

Nilsson Model ◽

Γ Rays ◽

Band Mixing ◽

Γ Ray

The 12C(12C,pγ)23Na reaction has been used to study the γ-ray deexcitation of levels up to Ex = 10.4 MeV in 23Na. Doppler-shift attenuation measurements yielded mean lifetimes or lifetime limits for 22 levels. Branching ratios were obtained for the 5.54, 6.11, 6.24, and 6.35 MeV levels and the major modes of decay were observed for 7 levels above Ex = 7 MeV. Angular distributions were measured for γ rays in coincidence with proton groups corresponding to the 5.54, 6.11, 6.24, 6.35, 9.04, and 10.35 MeV levels. The 6.35 MeV level is assigned a spin and parity of 9/2− and interpreted as a member of the low-lying Kπ = 1/2− band in 23Na. Levels at 9.04 and 10.35 MeV are interpreted as the 15/2+ and 13/2− members of the ground-state rotational band and Kπ = 1/2− band, respectively. The experimental γ-ray transition strengths in 23Na are compared to those predicted by the Nilsson model including band mixing. The M1 strengths are modified to account for the effects of isospin.

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Nuclear g Factors in 55Fe

Canadian Journal of Physics ◽

10.1139/p73-093 ◽

1973 ◽

Vol 51 (7) ◽

pp. 707-712 ◽

Cited By ~ 7

Author(s):

P. G. Kerr ◽

A. W. Gibb ◽

J. A. Cameron

Keyword(s):

Excited States ◽

Gamma Rays ◽

Target Material ◽

Internal Field ◽

Angular Distributions ◽

Mixing Ratios ◽

Decay Gamma ◽

G Factors

The (α,n) reaction on natural chromium has been used to study levels in 55Fe up to 2.5 MeV excitation. Intensities and angular distributions of the decay gamma rays were measured, yielding branching and E2/M1 mixing ratios. In a magnetized target of the alloy Cr20Fe80, the rotation of the angular distributions was observed. Using recently determined lifetimes for the excited states and the average internal field of 277 kOe measured in the target material by Mössbauer absorption, the following g factors are obtained:[Formula: see text]

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Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon

The Journal of Chemical Physics ◽

10.1063/1.3643334 ◽

2011 ◽

Vol 135 (12) ◽

pp. 124309 ◽

Cited By ~ 11

Author(s):

Yan Sun ◽

Feng Chen ◽

Bing Cong Gou

Keyword(s):

Excited States ◽

Energy Levels ◽

Branching Ratios ◽

The Core

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(n,n′γ) studies of 114,116Cd

Canadian Journal of Physics ◽

10.1139/p80-002 ◽

1980 ◽

Vol 58 (1) ◽

pp. 8-15 ◽

Cited By ~ 4

Author(s):

T. M. Newton ◽

J. M. Davidson ◽

W. K. Dawson ◽

P. W. Green ◽

H. R. Hooper ◽

...

Keyword(s):

Gamma Ray ◽

Energy Levels ◽

Angular Distributions ◽

Mixing Ratios

Energy levels below 2.2 MeV excitation in 114,116Cd have been investigated using the (n, n′γ) reaction. Gamma-ray angular distributions were measured, and energy levels, spins, and gamma-ray multipole mixing ratios were deduced. Levels and their spins have been confirmed at 1134 (0), 1210 (2), 1283 (4), 1365 (2), 1733 (4), and 1843 (2) keV for 14Cd and at 1213 (2), 1220 (4), and 1381 (0) keV for 116Cd. New spin assignments have been made for the levels at 1861 (3) and 2049 (3) keV for 114Cd and at 1644 (2,3) and 1917 (3) keV for 116Cd. The states at 1959 keV in 114Cd and 1923 keV in 116Cd are shown to be consistent with assignments of 3.

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Study of Λ-Hypernuclei with Stopped K− Reaction

Progress of Theoretical Physics Supplement ◽

10.1093/ptps.117.1 ◽

1994 ◽

Vol 117 ◽

pp. 1-15

Author(s):

Hirokazu Tamura ◽

Ryugo S. Hayano ◽

Haruhiko Outa ◽

Toshimitsu Yamazaki

Keyword(s):

Excited States ◽

Branching Ratios ◽

Future Prospects ◽

Mesonic Decay ◽

Peak Intensity ◽

Momentum Spectra ◽

Γ Ray ◽

Improved Accuracy ◽

First Time ◽

Nuclear Targets

We summarize studies of Λ hypernuclei with stopped K− reaction carried out at KEK. The π− momentum spectra in the (stopped K−, π−) reaction were measured with light nuclear targets (4He, 7Li, 9Be, 12C and 16O). The ground and excited states of Λ4He, Λ12C and Λ16O were identified and their formation probabilities were measured. The branching ratios of π0-mesonic decay of Λ4He, Λ11B and Λ12C were measured for the first time with π0 coincidence. The lifetime of Λ4H was also determined with an improved accuracy. The π− peak intensity from Λ4H→4He+π− decay gave the Λ4H formation probabilities on these targets, where Λ4H is produced as hyperfragment except for the case of the 4He target. Concerning the formation mechanism of hyperfragments and their application to hypernuclear γ-ray spectroscopy, the running experiments and future prospects are also described.

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An Investigation of Odd Parity States in 32S

Canadian Journal of Physics ◽

10.1139/p74-130 ◽

1974 ◽

Vol 52 (11) ◽

pp. 950-958 ◽

Cited By ~ 8

Author(s):

H. Grawe ◽

J. E. Cairns ◽

M. W. Greene ◽

J. A. Kuehner

Keyword(s):

Shell Model ◽

Excited States ◽

Linear Polarization ◽

Doppler Shift ◽

Polarization Measurement ◽

Angular Distributions ◽

Resonance States ◽

Mixing Ratios ◽

Model Predictions

States in 32S have been populated using the 31P(p,γ) reaction at the Ep = 895, 1438, and 1583 keV resonances. Angular distributions, a linear polarization measurement, and the results from the 32S(α,α′) reaction at 180° yielded the following spin and/or parity assignments for bound levels Jπ(6.62) = 4−, Jπ(6.76) = 3−, 4+, 5−, Jπ(6.85) = 3−, 4+, and Jπ(7.95) = 3, 4, 5−, and for resonance states J(10.26) = 4 and J(10.40) = 4. The γ decay of selected excited states has been studied and mixing ratios were obtained for the strongest branches. Doppler shift measurements yielded lifetimes of 810 (−250, +350) fs, > 300 fs and 110 (−40, +60) fs for the states at 6.62, 6.76, and 7.95 MeV respectively. The results are discussed and compared with shell model predictions.

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