A 20 MeV (p, d) study of nuclear structure in the even and odd tin isotopes

1982 ◽  
Vol 60 (4) ◽  
pp. 428-448 ◽  
Author(s):  
Donald G. Fleming
Keyword(s):  
Excitation Energy ◽  
Nuclear Structure ◽  
Born Approximation ◽  
Experimental Spectrum ◽  
Valence Neutron ◽  
Bcs Theory ◽  
Final States ◽  
Sum Rule ◽  
Spectroscopic Factors ◽  
Good Agreement

The nuclear structure of the even and odd tin isotopes has been studied by 20 MeV (p,d) reactions. States strongly populated in the odd isotopes are due to the valence neutron shells and extend up to only 2 MeV of excitation energy; "deep hole" states were not identified. The occupation probabilities extracted from finite-range distorted-wavc-Born-approximation calculations generally agree well with the predictions of the BCS theory of superconducting nuclei, particularly with the calculations of Clement and Baranger. In the even tin isotopes, strongly populated states are characterized predominantly by L = 2 transfers extending up to 4 MeV excitation energy. The experimental spectroscopic factors for transitions populating even final states are compared with the BCS calculated values of Clement and Baranger, Alzetta and Sawicki, and Van Gunsteren; relatively good agreement is obtained for L = 2 transitions, but not for L = 0 transitions. A considerable fraction of the expected sum rule L = 2 strength in 118Sn is missing in the 119Sn(p,d)118Sn experimental spectrum; in like manner, no 4+ strength could be identified in either 114Sn or 118Sn.

Using a double folding potential for the derivation of the spectroscopic factors of the (3He, d) transfer reaction

2016 ◽  
Vol 25 (09) ◽  
pp. 1650061 ◽  
Author(s):  
R. Pampa Condori ◽  
H. Dias ◽  
J. Lubian
Keyword(s):  
Born Approximation ◽  
Transfer Reaction ◽  
Distorted Wave ◽  
Distorted Wave Born Approximation ◽  
Model Calculations ◽  
Folding Potential ◽  
Spectroscopic Factors ◽  
Double Folding ◽  
Double Folding Potential ◽  
Good Agreement

In this paper, the [Formula: see text] reactions are revisited, with the goal of obtaining spectroscopic factors (SF) for the transition to the ground state of some residual nuclei, applying the distorted wave Born approximation (DWBA). The double-folding São Paulo Potential (SPP) was used to derive the distorted wave function in the entrance and exit channels. The derived SF are compared with the results of extensive shell model calculations showing a rather good agreement.

scholarly journals Study of 26Mg through 1p pick-up reaction 27Al(d,3He)

2017 ◽  
Vol 26 (10) ◽  
pp. 1750064 ◽  
Author(s):  
Vishal Srivastava ◽  
C. Bhattacharya ◽  
T. K. Rana ◽  
S. Manna ◽  
S. Kundu ◽  
...  
Keyword(s):  
Excitation Energy ◽  
Shell Model ◽  
Born Approximation ◽  
Beam Energy ◽  
Distorted Wave ◽  
Distorted Wave Born Approximation ◽  
Rotational Model ◽  
Spectroscopic Factors ◽  
Zero Range ◽  
Reaction 27Al

The reaction [Formula: see text]Al([Formula: see text],3He) at 25 MeV beam energy has been utilized to study the states in even–even nucleus [Formula: see text]Mg. The spectroscopic factors have been extracted for the states of [Formula: see text]Mg up to 7.50[Formula: see text]MeV excitation energy using local, zero-range distorted wave Born approximation. The extracted spectroscopic factors have been compared with the previously reported values. The present results were also compared with the predictions from a theoretical shell model and rotational model.

Rearrangement collisions: two-particle exchange

1964 ◽  
Vol 277 (1369) ◽  
pp. 206-213 ◽  
Keyword(s):  
Energy Dependence ◽  
Cross Section ◽  
Born Approximation ◽  
High Energy ◽  
Electron Exchange ◽  
Final States ◽  
Particle Exchange ◽  
Exchange Cross Section

It is shown that the first Bom approximation for the exchange of two uncorrelated electrons should vanish. A formalism for the T matrix is presented which has this property. The high-energy result for the two-electron exchange cross-section previously calculated in first Born approximation behaves like E -7 . This result is in error due to a lack of orthogonality of initial and final states. When this is corrected the result for uncorrelated electrons has an energy dependence E -11 . The introduction of correlation gives terms behaving like E -10 which cannot be calculated unam biguously.

Intermediate Coupling in 55Fe

1971 ◽  
Vol 49 (13) ◽  
pp. 1832-1835 ◽  
Author(s):  
M. Csürös ◽  
J. A. Cameron ◽  
Z. Zàmori
Keyword(s):  
Collective Model ◽  
Electromagnetic Properties ◽  
Intermediate Coupling ◽  
Spectroscopic Factors ◽  
Good Agreement

Calculations based on the collective model with intermediate coupling between the surface oscillations of the even–even core 54Fe and 29th neutron have been carried out. Level energies, spectroscopic factors, and electromagnetic properties are obtained in good agreement with experiment.

L X-ray fluorescence cross sections in the atomic region 59 ≤ Z ≤ 82 excited by 16.58 keV photons

1996 ◽  
Vol 74 (5-6) ◽  
pp. 230-235 ◽  
Author(s):  
D. V. Rao ◽  
R. Cesareo ◽  
G. E. Gigante
Keyword(s):  
Excitation Energy ◽  
Least Squares ◽  
Cross Sections ◽  
Experimental Results ◽  
X Ray ◽  
Experimental Cross ◽  
Average Fluorescence ◽  
Good Agreement

LL, Lα, Lβ, and Lγ X-ray fluorescence cross sections for Pr, Sm, Gd, Dy, Ho, Er, Yb, Pt Au, and Pb were measured at the excitation energy 16.58 keV. An X-ray tube and a secondary excitor system was used instead of radioisotopes for the measurements. Experimental cross sections are compared with the theoretical estimates based on relativistic Dirac–Hartree–Slater theory. Average L-shell fluorescence yields [Formula: see text] are deduced using the present experimental cross sections and the theoretical subshell photoionization cross sections. The derived average fluorescence yields are fitted by least squares to polynomials in Z of the form ΣnanZn and compared with theoretical and earlier fitted values. Good agreement is observed ' between the experimental results and the theoretical estimates based on relativistic Dirac–Hartree–Slater theory.

scholarly journals Electron Momentum Spectroscopy

1986 ◽  
Vol 39 (5) ◽  
pp. 587 ◽  
Author(s):  
IE McCarthy
Keyword(s):  
Impulse Approximation ◽  
High Electron ◽  
Final States ◽  
Final State ◽  
Structure Information ◽  
Plane Wave Impulse Approximation ◽  
Ion Structure ◽  
Spectroscopic Factors ◽  
Electron Momentum Spectroscopy ◽  
Energy And Momentum

For sufficiently high electron energies (greater than a few hundred eV) and sufficiently low recoil momenta Oess than a few atomic units) the differential cross section for the non-coplanar symmetric (e,2e) reaction on an atom or molecule depends on the target and ion structure only through the target-ion overlap. Experimental criteria for the energy and momentum are that the apparent structure information does not change when the energy and momentum are varied. The plane-wave impulse approximation is a sufficient description of the reaction mechanism for determining spherically averaged squares of momentum-space orbitals for atoms and molecules and for coefficients describing initial- and final-state correlations. For mainly uncorrelated initial states, spectroscopic factors for final states belonging to the same manifold are uniquely determined. For molecules, summed spectroscopic factors can be compared for different ion manifolds. For atoms, summed spectroscopic factors and higher-momentum profiles require the dist~rted-wave impulse approximation.

Shape coexistence in $^{76}$Se within the neutron-proton interacting boson model

2021 ◽  
Author(s):  
Chengfu Mu ◽  
Dali Zhang
Keyword(s):  
Experimental Data ◽  
Energy Spectrum ◽  
Excitation Energy ◽  
Energy Levels ◽  
Spherical Shape ◽  
Interacting Boson Model ◽  
Shape Coexistence ◽  
Electromagnetic Transition ◽  
Boson Model ◽  
Good Agreement

Abstract We have investigated the low-lying energy spectrum and electromagnetic transition strengths in even-even $^{76}$Se using the proton-neutron interacting boson model (IBM-2). The theoretical calculation for the energy levels and $E2$ and $M1$ transition strengths is in good agreement with the experimental data. Especially, the excitation energy and $E2$ transition of $0^+_2$ state, which is intimately associated with shape coexistence, can be well reproduced. The analysis on low-lying states and some key structure indicators indicates that there is a coexistence between spherical shape and $\gamma$-soft shape in $^{76}$Se.

scholarly journals STATUS OF THE HADRONIC τ DETERMINATION OF Vus

2008 ◽  
Vol 23 (21) ◽  
pp. 3191-3195 ◽  
Author(s):  
K. MALTMAN ◽  
C. E. WOLFE ◽  
S. BANERJEE ◽  
M. RONEY ◽  
I. NUGENT
Keyword(s):  
Sum Rules ◽  
Branching Fractions ◽  
Sum Rule ◽  
Slow Convergence ◽  
Decay Data ◽  
Decay Modes ◽  
Good Agreement

We update the extraction of Vus from hadronic τ decay data in light of recent BaBar and Belle results on the branching fractions of a number of important strange decay modes. A range of sum rule analyses is employed, particular attention being paid to those based on “non-spectral weights”, developed previously to bring the slow convergence of the relevant integrated D = 2 OPE series under improved control. Results from the various sum rules are in good agreement with one another, but ~ 3σ below expectations based on 3-family unitarity.

scholarly journals Scattering of Alpha-particles by a Vibrational Nucleus

1962 ◽  
Vol 15 (2) ◽  
pp. 135 ◽  
Author(s):  
LJ Tassie
Keyword(s):  
Elastic Scattering ◽  
Plane Wave ◽  
Experimental Test ◽  
Born Approximation ◽  
Alpha Particles ◽  
Nuclear Surface ◽  
Vibrational States ◽  
Phonon Excitation ◽  
Plane Wave Born Approximation ◽  
Good Agreement

The elastic and inelastic scattering of cx-particles by a vibrational nucleus is calculated using plane-wave Born approximation. The excitation of both single-phonon and twophonon states is considered. The effect of the diffuseness of the nuclear surface is included. The result for elastic scattering and the excitation of the single-phonon 2+ and 3- states is in good agreement with experiment for .oNi. The approximations used are discussed, and it is suggested that excitation of 0+, 1-, and 5- states should provide the best experimental test of the theory of two-phonon excitation of nuclei. The energies of the vibrational states are also considered.

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