Recent Articles

${}^{6}{Li}$ , ${}^{7}{Li}$ induced reactions on ${}^{209}{Bi}$

H. Freiesleben, H. C. Britt, J. Birkelund, and J. R. Huizenga

Phys. Rev. C 10, 245 (1974) - Published 1 July, 1974

Show Abstract

Results are reported on experimental measurements of total cross sections for ( ${}^{6, 7}{Li}, xn$ ), ( ${}^{6, 7}{Li}, f$ ), ( ${}^{7}{Li}, α xn$ ), ( ${}^{7}{Li}, txn$ ), and ( ${}^{7}{Li}, α p$ ) reactions on a ${}^{209}{Bi}$ target at bombarding energies in the range 25-34 MeV. At ${}^{7}{Li}$ bombarding energies of 32 and 30 MeV, the cross sections for transfer reactions are 57 and 70%, respectively, of the total measured cross section. At energies below the Coulomb barrier, the cross section for transfer reactions becomes considerably larger than those for compound nucleus reactions.

NUCLEAR REACTIONS ${}^{209}{Bi} ({}^{6, 7}{Li}, x n)$ , ( ${}^{6, 7}{Li}, f$ ), ( ${}^{7}{Li}, α xn$ ), ( ${}^{7}{Li}, txn$ ), ( ${}^{7}{Li}, α p$ ), $E = 25 - 34$ MeV; measured $σ (E)$ .

Experimental study of collective properties of ${}^{152}{Sm}$ by multiple Coulomb excitation

J. M. Domingos, G. D. Symons, and A. C. Douglas

Phys. Rev. C 10, 250 (1974) - Published 1 July, 1974

Show Abstract

Collective states in ${}^{152}{Sm}$ have been studied by multiple Coulomb excitation with 41.0-59.1 MeV ${}^{16}O$ ions. The excitation probabilities for the $2^{+}$ , $4^{+}$ , $6^{+}$ , and $8^{+}$ states of the ground state rotational band, the $0^{+}$ , $2^{+}$ , and $4^{+}$ states of the $β$ vibrational band, the $2^{+}$ and $4^{+}$ states of the $γ$ vibrational band and the $1^{-}$ , $3^{-}$ , and $5^{-}$ states of the octupole band have been measured. The angular correlations and branching ratios for the strongest transitions deexciting these states have also been measured. From these correlations the $\frac{E 2}{M 1}$ mixing ratios have been obtained for the $2_{β} \to 2$ , $4_{β} \to 4$ , $2_{γ} \to 2$ , and $4_{γ} \to 4$ transitions. Deviations of both the branching ratios from the $β$ and $γ$ bands and the excitation probabilities for states in the ground state band from the simple rotational predictions are examined in terms of the modified rotational model with first order band mixing between the ground state band, $γ$ , and $β$ bands. It is shown that although this model gives satisfactory agreement with the multiple Coulomb excitation theory for the excitation probabilities, the branching ratios for decay of the $2_{β}$ and $4_{β}$ states are not consistent, as has previously been shown in radioactive decay studies. The transition probabilities within the ground state band and from the $0_{β}$ state are compared with recent accurate measurements of the lifetimes of these states by the recoildistance Doppler shift technique.

NUCLEAR REACTIONS ${}^{152}{Sm} ({}^{16}O, {}^{16}O^{'} γ)$ , $E = 41.0 - 59.1$ MeV; measured $σ (E)$ , measured $I_{γ}$ , ${}^{16}O^{'} γ (θ)$ . Deduced $σ (\frac{E 2}{M 1})$ , band-mixing parameters $Z_{0}$ , $Z_{2}$ . Enriched targets; Ge(Li) detector.

Electric moments and charge deformation in even rare-earth nuclei

Alan H. Shaw and J. S. Greenberg

Phys. Rev. C 10, 263 (1974) - Published 1 July, 1974

Show Abstract

We present measurements of $E 2$ and $E 4$ transition matrix elements, and related $β_{2}$ and $β_{4}$ deformations, for eight even rare earth nuclei, by exploiting the effect of electric quadrupole and electric hexadecapole excitation on the multiple Coulomb excitation of states in their ground state bands. The Coulomb excitation probabilities for the $0^{+}$ , $2^{+}$ , and $4^{+}$ states in the ground state bands of the even rare earth nuclei ${}^{152, 154}{Sm}$ , ${}^{158, 160}{Gd}$ , ${}^{164}{Dy}$ , ${}^{166, 168}{Er}$ , and ${}^{174}{Yb}$ have been measured with ${}^{4}{He}$ projectiles at several incident energies below the respective Coulomb barriers by direct detection, at backward angles, of elastically and inelastically scattered particles. The direct detection of scattered ${}^{4}{He}$ particles was employed in order to eliminate the uncertainties involved in the detection of the deexcitation $γ$ rays, and to facilitate the determination of $M (E 2; 0^{+} \to 2^{+})$ to about the $\frac{1}{2}$ % accuracy required to obtain a meaningful measurement of $M (E 4; 0^{+} \to 4^{+})$ . Coulomb-nuclear interference effects in elastic and inelastic scattering were investigated, and it was demonstrated that Coulomb nuclear interference occurs at a much lower projectile energy than predicted by the simple classical formula for the Coulomb barrier, and manifests itself at different incident energies for elastic and inelastic scattering. The data on excitation probabilities were analyzed both with a semiclassical Coulomb excitation calculation, corrected for quantal effects in second order perturbation theory, and with a full quantal calculation, to determine the reduced electric transition matrix elements $M (E 2; 0^{+} \to 2^{+})$ and $M (E 4; 0^{+} \to 4^{+})$ . Significant differences were found between the perturbation theory quantal treatment and the full quantal calculations. Static quadrupole and hexadecapole moments of the charge distribution were extracted from the measured transition matrix elements within the context of the rotational model. Using an axially symmetric deformed Fermi shape to parametrize the charge distribution, charge deformation parameters $β_{2}^{C}$ and $β_{4}^{C}$ deduced from the static moments, were found to follow the same general trends as the potential deformation parameters measured in nuclear scattering experiments well above the Coulomb barrier. For some nuclei the Coulomb excitation $β_{λ}^{C}$ values show what may be significant deviations from the nuclear potential deformations parameters. However, it is emphasized that, presently, the significance of such a comparison as well as the significance of a comparison with deformation parameters determined with other electromagnetic probes, is subject to the considerations introduced by the model dependence of each measurement, and diluted by the ambiguous correspondence between the quantities being measured in the different experiments.

NUCLEAR REACTIONS ${}^{152, 154}{Sm} (α, α^{'})$ , ${}^{158, 160}{Gd} (α, α^{'})$ , ${}^{164}{Dy} (α, α^{'})$ , ${}^{166, 168}{Er} (α, α^{'})$ , ${}^{174}{Yb} (α, α^{'})$ , $E_{α} = 8 - 17$ MeV; measured Coulomb excitation probabilities. Deduced $B (E 2)$ , $B (E 4)$ ; extracted $β_{2}$ , $β_{4}$ from rotational model and Fermi charge distribution. Enriched targets.

Influence of the particle-number fluctuation on the $E 1$ $Δ K = \pm 1$ transitions in deformed odd-mass nuclei

M. Fellah and T. F. Hammann

Phys. Rev. C 10, 284 (1974) - Published 1 July, 1974

Show Abstract

Dipole electric transitions with $Δ K = \pm 1$ are studied theoretically for odd-mass nuclei in the rare-earth region (i) in the frame work of an elaborated Nilsson model with rotation-particle coupling and with isospin-dependent parameters, (ii) with the usual BCS wave function, and (iii) with sharp particle-number-projected BCS wave functions. These projected wave functions are the limit of very speedily converging sequences of functions. General formulas for the pairing reduction factors with strict nucleon number conservation are established. The unphysical effects due to particle fluctuation in the usual BCS wave functions are found to be very important in the theoretical BCS evaluation of reduction factors and half-lives. In most of the analyzed $E 1$ transitions, the hindrance factors are improved by the elimination of the unphysical effects due to particle fluctuation. The blocking effect is systematically taken into account. The importance and validity of the physical and mathematical approximations used is discussed.

RADIOACTIVITY ${}^{153, 155}{Eu}$ ; ${}^{159, 161}{Tb}$ ; ${}^{175, 177}{Lu}$ ; ${}^{179, 181}{Ta}$ ; ${}^{155, 157}{Gd}$ ; ${}^{161}{Dy}$ ; ${}^{169, 171, 173, 177}{Yb}$ ; ${}^{175, 177, 179}{Hf}$ ; $E 1$ $Δ K = \pm 1$ particle-number-projected pairing reduction factor and $T_{\frac{1}{2}}$ .

$α$ -decay branching ratios for high - and low -spin isomers in ${}^{151, 152, 153, 154}{Ho}$

W-D. Schmidt-Ott, K. S. Toth, E. Newman, and C. R. Bingham

Phys. Rev. C 10, 296 (1974) - Published 1 July, 1974

Show Abstract

$α$ -decay branching ratios were obtained for high- and low-spin isomers in ${}^{151, 152, 153, 154}{Ho}$ . These activities were produced by bombarding ${}^{144, 147}{Sm}$ with ${}^{11, 10}B$ ions, respectively, accelerated in the Oak Ridge isochronous cyclotron. With the use of a gas-jet-capillary transport system it was possible to do $α$ -particle, x-ray, and $γ$ -ray counting simultaneously. Branching ratios were deduced in the main by determining the number of $K α_{1}$ x rays emitted and then applying appropriate correction factors to obtain the total number of electron-capture and positron decays. For ${}^{152, 154}{Ho}$ , where the $γ$ -ray spectral measurements could be used to extract information concerning their decay to ${}^{152, 154}{Dy}$ , it was possible to deduce alternate, and thus independent, $α$ -decay branching ratios. (Incidentally, our results confirm those of Ward and Neiman for the decay of the high-spin ${}^{154}{Ho}$ isomer to levels in ${}^{154}{Dy}$ .) Within error limits the two sets of ratios for ${}^{152, 154}{Ho}$ were found to be in agreement. For the two cases, i.e., 35.6-sec ${}^{151}{Ho}$ and 9.3-min ${}^{153}{Ho}$ , where experimental $α$ -decay branches had been previously measured our data agree with the earlier results. $α$ -decay reduced widths were calculated by using the formalism developed by Rasmussen and compared with values for neighboring even-even nuclei, which can be taken to represent unhindered $α$ decay. The present study is the first systematic investigation of $α$ -decay rates for a series of isotopes of an odd- $Z$ element in the rare earth region. It was found that, as for odd- $A$ isotopes in the heavy-element region, the $α$ -decay reduced widths range from those of even-even nuclei down to much smaller values.

RADIOACTIVITY ${}^{151, 152, 153, 154}{Ho}$ ; $I_{α}$ , $I_{(K α x ray)}$ , $I_{γ}$ , $E_{γ}$ ; measured $α$ -decay branching ratios; deduced $α$ -decay rates. ${}^{152, 154}{Dy}$ deduced levels, $J$ , $π$ .

Optical-model analysis of $p + {}^{208}{Pb}$ elastic scattering from 15 - 1000 MeV

W. T. H. van Oers, Huang Haw, N. E. Davison, A. Ingemarsson, B. Fagerström, and G. Tibell

Phys. Rev. C 10, 307 (1974) - Published 1 July, 1974

Show Abstract

Measurements have been made of the differential cross sections for $p + {}^{208}{Pb}$ elastic scattering at mean proton energies of 21.0, 24.1, 26.3, 30.5, 35.0, 45.0, and 47.3 MeV. Measurements have also been made of the differential cross sections and polarizations at 185 MeV. These data together with the data in the energy range 15-1000 MeV available in the literature have been analyzed in terms of a standard 11-parameter optical model. Relativistic corrections to the optical-model analysis were introduced. The energy dependence of the real central potential (as indicated by the volume integral per nucleon and by the strength parameter) can be represented by a linear relation if a limited energy range is chosen. This linear energy relation cannot be extrapolated to higher energies since it makes the real central potential repulsive at too low an energy as indicated by the results of optical-model analyses of proton scattering data above 200 MeV. A logarithmic energy dependence gives a reasonable presentation of the volume integral per nucleon of the real central potential for energies up to 1 GeV.

NUCLEAR SCATTERING ${}^{208}{Pb} (p, p)$ , $T = 21.0, 24.1, 26.3, 30.5, 35.0, 45.0, and 47.3$ MeV, measured $σ (θ)$ , $θ = 15 - 167.5 °$ ; $T = 185$ MeV measured $σ (θ)$ , $P (θ)$ , $θ = 4 - 38 °$ ; optical-model analysis, previous data $σ (θ)$ , $P (θ)$ , $σ^{R}$ included.

Parity non-conservation in the alpha particle decay of the 8.87 MeV $2^{-}$ state of ${}^{16}O$

K. Neubeck, H. Schober, and H. Wäffler

Phys. Rev. C 10, 320 (1974) - Published 1 July, 1974

Show Abstract

The energy spectrum of 2.5× $10^{8}$ $α$ particles from the sequential decay ${}^{16}N (β^{-}) {}^{16}O (α) {}^{12}C$ has been analyzed. Superimposed on the broad energy distribution which originated from the decay of the $1^{-}$ 9.60 MeV state of ${}^{16}O$ into ${}^{12}C + α$ , a group of 9538 ± 1810 $α$ particles with an energy of 1282 keV has been identified with a maximum error of ± 5 keV. This group is attributed to the parity non-conserving decay from the $2^{-}$ 8.87 MeV state of ${}^{16}O$ into ${}^{12}C + α$ ; the $α$ -particle emission width for this decay has been determined to be $Γ_{α}$ = (1.03 ± 0.28) × $10^{- 10}$ eV. In a separate measurement the relative ${}^{16}N$ $β$ decay branching ratio to the 9.60 and 8.87 MeV states in ${}^{16}O$ , which was necessary for the calculation of $Γ_{α}$ , has been determined to be (9.98 ± 0.70) × $10^{- 4}$ .

RADIOACTIVITY ${}^{16}N (β^{-}) {}^{16}O (α) {}^{12}C$ ; measured energy spectrum; deduced $α$ -particle group $E_{α} = 1282 \pm 5$ keV attributed to parity non-conserving $α$ -particle decay ${}^{16}O (8.87 MeV 2^{-}) \to {}^{12}C + α$ ; deduced $Γ_{α} = (1.03 \pm 0.28) \times 10^{- 10}$ eV.

$β$ decay of ${}^{12}B$ and ${}^{12}N$

R. E. McDonald, J. A. Becker, R. A. Chalmers, and D. H. Wilkinson

Phys. Rev. C 10, 333 (1974) - Published 1 July, 1974

Show Abstract

The $β$ decays of ${}^{12}B$ and ${}^{12}N$ to the first excited state of ${}^{12}C$ have been compared by detecting the $β$ particles in $4 π$ geometry and simultaneously collecting $β - γ$ coincidences. All events were time sorted so that the ${}^{12}B$ , ${}^{12}N$ components of the $β$ and $β - γ$ coincidence spectra could be accurately extracted down to low values of the $β$ -particle energy. For the ratio of the branching ratios ${}^{12}N$ / ${}^{12}B$ we find 1.74 ± 0.08. This and other data are analyzed to extract the $β$ -decay asymmetry $[\frac{{(ft)}^{+}}{{(ft)}^{-}}] - 1 = - 0.013 \pm 0.066$ . All existing data on asymmetry in Gamow-Teller $β$ decay in even- $A$ nuclei of the $1 p$ shell are analyzed in the light of the work of Kubodera, Delorme, and Rho that, using appropriate many-body wave functions, relates the asymmetry to two fundamental second class current parameters $ζ$ and $λ$ . We find, at the 99% confidence limit, $| ζ | < 4 \times 10^{- 3}$ ${MeV}^{- 1}$ ; $| λ | < 1.5 \times 10^{- 2}$ . In the model that ascribes all second class current effects to the $G$ -parity-violating decay $ω \to π e ν$ both as an exchange term (which enters into $λ$ ) and as a nucleon decay vertex renormalization term (which determines $ζ$ and enters into $λ$ ), our results correspond to $T_{ω \to π e ν} > 5 \times 10^{- 11}$ sec. This limit corresponds, using SU(3), to the expectation that the asymmetry in $Σ \to Λ e ν$ decay is less than 25%.

NUCLEAR STRUCTURE ${}^{12}B$ , ${}^{12}N$ ; measured ratio of branching ratios to ${}^{12}C$ (4.44); deduced $β$ -decay asymmetry. Nuclear $1 p$ -shell $β$ -decay asymmetry parameters deduced second class current parameters $ζ$ , $λ$ ; calculated limits $τ (ω \to π e ν)$ , asymmetry $Σ \to Λ e ν$ .

Deuteron electromagnetic structure at large momentum transfer

M. Chemtob, E. J. Moniz, and M. Rho

Phys. Rev. C 10, 344 (1974) - Published 1 July, 1974

Show Abstract

Pursuing the idea that exchange currents should dominate the very large momentum transfer behavior of the deuteron electromagnetic form factors, we evaluate the $π ρ$ and $σ ω$ exchange contributions. Taking the meson-nucleon coupling constants from one-boson exchange calculations of the $NN$ force and the photon-meson coupling strengths from a relativistic quark model, we find that the form factors begin to "flatten out" at momentum transfers $q^{2} ≳ 50$ ${fm}^{- 2}$ and are an order of magnitude greater than the usual impulse prediction at $q^{2} \approx 100$ ${fm}^{- 2}$ .

NUCLEAR STRUCTURE ${}^{2}H$ ; calculated exchange current effects in large momentum transfer electromagnetic form factors.

Lifetime measurements and collective behavior in ${}^{49}V$

S. L. Tabor and R. W. Zurmühle

Phys. Rev. C 10, 35 (1974) - Published 1 July, 1974

Show Abstract

Lifetimes of levels in ${}^{49}V$ have been measured using the Doppler-shift attenuation method. States were populated with the ${}^{46}{Ti} (α, p) {}^{49}V$ reaction at a beam energy of 10 MeV. Protons were detected near 180° relative to the beam and most Doppler shifts were measured between $γ$ spectra accumulated at $θ_{γ} = 53 and 140 °$ . Values or limits were obtained for the mean lifetimes of 25 levels in ${}^{49}V$ from 748 to 2812 keV in excitation energy. The positive parity levels appear to form two rotational bands with $K^{π} = {\frac{3}{2}}^{+} and {\frac{1}{2}}^{+}$ . The first 2 MeV of the negative parity level scheme is reproduced rather well with calculations using the strong coupling model. This model also predicts the transition strengths reasonably well. These results suggest strong collective behavior in the states of both parities.

NUCLEAR REACTIONS ${}^{46}{Ti} (α, p γ)$ , $E_{γ} = 10$ MeV; measured Doppler-shift attenuation. ${}^{49}V$ deduced levels, $τ$ , $J$ , $π$ , $B (Λ)$ , branching ratios. Enriched target.

Mass parameter in nuclear quadrupole motion

P. K. Haff and L. Wilets

Phys. Rev. C 10, 353 (1974) - Published 1 July, 1974

Show Abstract

The self-cranked generator coordinate (SCGC) formalism described earlier for computing the mass parameter for collective nuclear motion is cast into a form containing no explicit reference to the Hamiltonian. The expression is then specialized to the nuclear model of deformed harmonic oscillators. The usual Gaussian overlap approximation is eschewed in favor of direct evaluation of the appropriate matrix elements. Exchange terms are handled by a diagrammatic technique. The validity of certain assumptions made in the derivation of the mass formula is tested numerically. The effects of pairing and of short-range Jastrow correlations are investigated. The SCGC mass parameter is computed for several $N = Z$ nuclei and found to be smaller than either the cranking or the irrotational values, if no correlations are included. The inclusion of short-range correlations is shown to lead to important changes in the value of the mass parameter.

NUCLEAR STRUCTURE Quadrupole mass parameter calculated. Self-cranked generator coordinate formalism. Correlations included. Compared to irrotational flow values.

Comment on a new method for phase shift computation

K. L. Kowalski

Phys. Rev. C 10, 366 (1974) - Published 1 July, 1974

Show Abstract

A method for computing phase shifts recently proposed by Bolsterli based upon a new non-singular scattering integral equation is shown to be a special case of the so-called generalized Sasakawa technique. This observation leads to a simplification of the practical exploitation of the method as well as an extension to the calculation of half-off-shell amplitudes.

Proton-deuteron double scattering

John W. Wilson

Phys. Rev. C 10, 369 (1974) - Published 1 July, 1974

Show Abstract

A simple but accurate form for the proton-deuteron elastic double scattering amplitude, which includes both projectile and target recoil motion and is applicable at all momentum transfer, is derived by taking advantage of the restricted range of Fermi momentum allowed by the deuteron wave function. This amplitude can be directly compared to approximations which have neglected target recoil or are limited to small momentum transfer; the target recoil and large momentum transfer effects are evaluated explicitly within the context of a Gaussian model.

NUCLEAR REACTIONS Double scattering, proton-deuteron scattering, multiple scattering theory.

Violation of isospin conservation in two-nucleon pickup reactions?

D. J. Crozier and H. T. Fortune

Phys. Rev. C 10, 377 (1974) - Published 1 July, 1974

Show Abstract

The recently reported differences in the analog reactions ${}^{16}O (p, {}^{3}{He}) {}^{14}N$ (2.31 MeV) and ${}^{16}O (p, t) {}^{14}O$ (g.s.) are correctly predicted by distorted-wave Born-approximation calculations, using standard parameters with no adjustments.

NUCLEAR REACTIONS ${}^{16}O (p, t)$ and ${}^{16}O (p, {}^{3}{He})$ , $E = 27$ MeV; calculated $σ (θ)$ , ratio.

Mean excitation energies in the nuclear muon capture

Francesco Cannata and Nimai C. Mukhopadhyay

Phys. Rev. C 10, 379 (1974) - Published 1 July, 1974

Show Abstract

The parametrization of the total muon capture rates in terms of a mean nuclear excitation energy ${\bar{E}}^{'}$ , proposed in a recent letter of Christillin, Dellafiore, and Rosa-Clot (CDR), is examined. We show that this parametrization ignores the importance of the allowed transitions in light nuclei and fails to reproduce the experimentally observed trend of the $T_{>}$ giant resonance energy as a function of nuclear mass number. The removal of contributions due to higher multipoles in heavier nuclei aggravates this discrepancy. The failure of ${\bar{E}}^{'}$ , extracted by CDR, to correspond to physically meaningful nuclear excitation energies in heavier nuclei is attributable to the intrinsic arbitrariness in its definition, and to the oversimplifying assumption of the nuclear Hamiltonian to be a sum of kinetic energy and Wigner potential alone. A first-order improvement of the Primakoff approximation is discussed.

NUCLEAR REACTIONS $μ^{-} + A (N, Z) \to v + A (N + 1, Z - 1)$ ; muon capture; closure approximation; mean nuclear excitation energies.

Redetermination of the half-life of ${}^{235}U$ for $α$ emission

A. J. Deruytter and Gerda Wegener-Penning

Phys. Rev. C 10, 383 (1974) - Published 1 July, 1974

Show Abstract

Measurements with a low counting geometry and a 99.999% ${}^{235}U$ source were carried out to determine branching ratios in the α decay. The ${}^{235}U$ half-life was calculated, relative to that of ${}^{238}U$ . The result is $T_{\frac{1}{2}} ({}^{235}U) = (6.85 \pm 0.09) \times 10^{8}$ yr.

RADIOACTIVITY ${}^{235}U$ ; measured $α - decay$ branching; deduced $T_{\frac{1}{2}}$ $α$ emission.

Redetermination of the half-life of ${}^{235}U$ for $α$ emission: A reply

Arthur H. Jaffey

Phys. Rev. C 10, 386 (1974) - Published 1 July, 1974

Show Abstract

RAPID COMMUNICATION

Spectrum of protons in fission of ${}^{252}{Cf}$

A. Gavron and Y. Gazit

Phys. Rev. C 10, 388(R) (1974) - Published 1 July, 1974

Show Abstract

The spectrum of protons in fission of ${}^{252}{Cf}$ has been measured using an improved collimation technique, which eliminates a large part of the background. The most probable proton energy was determined to be 7.8 ± 0.2 MeV and the spectrum full width at half-maximum, 6.1 ± 0.3 MeV. The number of protons emitted per long range α particle is (1.6 ± 0.1) × $10^{- 2}$ .

RADIOACTIVITY, FISSION ${}^{252}{Cf (Sf)}$ ; measured proton spectrum.

RAPID COMMUNICATION

Accurate momentum-space method for scattering by nuclear and Coulomb potentials

C. M. Vincent and S. C. Phatak

Phys. Rev. C 10, 391(R) (1974) - Published 1 July, 1974

Show Abstract

RAPID COMMUNICATION

Formula for the fluctuation cross section of nuclear reactions at low energies

M. S. Hussein

Phys. Rev. C 10, 395(R) (1974) - Published 1 July, 1974

Show Abstract

An expression is derived for the total fluctuation cross section valid for the general case of any number of directly coupled open channels. In the limit when this number is very large one recovers the familiar Hauser-Feshbach result for inelastic scattering. A different result emerges for the elastic case. Generally for many overlapping resonances $\frac{σ_{c c^{'}}}{(2 l + 1) π λ_{c^{'}}} = (\frac{N - 1}{N + 1} δ_{c c^{'}} + 1) \frac{P_{c} P_{c^{'}}}{Σ \overset{}{c^{''}} P_{c^{''}}} .$

Select page:

Physical Review C

Recent Articles

Filter

Recent Issues

${}^{6}{Li}$ , ${}^{7}{Li}$ induced reactions on ${}^{209}{Bi}$

Experimental study of collective properties of ${}^{152}{Sm}$ by multiple Coulomb excitation

Electric moments and charge deformation in even rare-earth nuclei

Influence of the particle-number fluctuation on the $E 1$ $Δ K = \pm 1$ transitions in deformed odd-mass nuclei

$α$ -decay branching ratios for high - and low -spin isomers in ${}^{151, 152, 153, 154}{Ho}$

Optical-model analysis of $p + {}^{208}{Pb}$ elastic scattering from 15 - 1000 MeV

Parity non-conservation in the alpha particle decay of the 8.87 MeV $2^{-}$ state of ${}^{16}O$

$β$ decay of ${}^{12}B$ and ${}^{12}N$

Deuteron electromagnetic structure at large momentum transfer

Lifetime measurements and collective behavior in ${}^{49}V$

Mass parameter in nuclear quadrupole motion

Comment on a new method for phase shift computation

Proton-deuteron double scattering

Violation of isospin conservation in two-nucleon pickup reactions?

Mean excitation energies in the nuclear muon capture

Redetermination of the half-life of ${}^{235}U$ for $α$ emission

Redetermination of the half-life of ${}^{235}U$ for $α$ emission: A reply

Spectrum of protons in fission of ${}^{252}{Cf}$

Accurate momentum-space method for scattering by nuclear and Coulomb potentials

Formula for the fluctuation cross section of nuclear reactions at low energies

Filter

Recent Issues

Filter

Article Lookup

Enter a citation