Recent theoretical developments in nuclear charge-exchange reactions

The (p, n) and (n, p) charge-exchange reactions are a suitable tool in nuclear-structure studies. At intermediate energies, the interaction with the target resembles that between free nucleons, which makes the probes mostly susceptible to the spin dynamics of the nucleus. We review the current theoretical picture of nucleon–nucleus charge-exchange reactions. A brief introduction to the theory of direct reactions in the impulse approximation is given. We then discuss the random-phase approximation (RPA) linear response theory, which is widely used in the calculation of cross sections and related observables. To understand correctly the shape of the continuum cross sections, one needs a more sophisticated theory. We discuss suitable extensions of the RPA that incorporate spreading effects as well as escape effects. Charge-exchange reactions of the (n, p) type have important implications for the evolution of massive stars. The relevance for Type-II supernovae is discussed.

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Charge exchange reactions on medium and heavy mass targets at intermediate energies

Modern Physics Letters A ◽

10.1142/s0217732320500455 ◽

2019 ◽

Vol 35 (08) ◽

pp. 2050045

Author(s):

Pardeep Singh ◽

Monika Singh ◽

Neha Rani

Keyword(s):

Charge Exchange ◽

Cross Sections ◽

Energy Charge ◽

Impulse Approximation ◽

Mass Region ◽

Intermediate Energy ◽

Exchange Reactions ◽

Plane Wave Impulse Approximation ◽

Text Type ◽

Intermediate Energies

The nuclear isotopic structure can be understood easily via the intermediate-energy charge exchange reactions of (p, n) and [Formula: see text]He, [Formula: see text] type. In the current contribution, we present some results for charge exchange reactions induced by 3He on targets lying in mass region [Formula: see text] within the theoretical framework of plane wave impulse approximation (PWIA) and distorted wave impulse approximation (DWIA). Here, the recoil effects in PWIA have also been considered. Particularly, the angular distributions and the unit cross-sections have been calculated and compared with the available data. Further, the importance of inclusion of the exchange contribution in these reactions is also considered, which eventually enhance the matching with data.

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Nucleon charge-exchange reactions at intermediate energies

Canadian Journal of Physics ◽

10.1139/p87-077 ◽

1987 ◽

Vol 65 (6) ◽

pp. 536-548 ◽

Cited By ~ 21

Author(s):

W. G. Love ◽

Amir Klein ◽

M. A. Franey ◽

K. Nakayama

Keyword(s):

Charge Exchange ◽

Random Phase ◽

Impulse Approximation ◽

Nucleon Nucleon ◽

Large Momentum ◽

Nuclear Excitation ◽

Exchange Reactions ◽

Charge Exchange Reaction ◽

Intermediate Energies ◽

Nucleon Nucleon Interaction

The nucleon charge–exchange reaction is investigated as a probe of isovector modes of nuclear excitation at both small and large momentum transfer. The calculated and extracted properties of the isovector nucleon–nucleon interaction are discussed and illustrated with an emphasis on incident energies in excess of 100 MeV. Particular emphasis is placed on spin observables and the roles played by different parts of the nucleon–nucleon coupling in their determination. Recent measurements of transverse polarization transfer at 0° in the charge-exchange continuum are compared with distorted wave impulse approximation calculations using random–phase approximation transition densities.

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Multipole decomposition of Gamow–Teller strength

Canadian Journal of Physics ◽

10.1139/p87-094 ◽

1987 ◽

Vol 65 (6) ◽

pp. 660-665 ◽

Cited By ~ 41

Author(s):

Murray A. Moinester

Keyword(s):

Charge Exchange ◽

Cross Sections ◽

Present Report ◽

Random Phase ◽

Impulse Approximation ◽

General Importance ◽

Least Squares Fit ◽

Distorted Wave Impulse Approximation ◽

One Step ◽

Gamow Teller

Doubly differential continuum cross sections from the 90Zr(p, n)90Nb reaction have been analyzed via a multipoledecomposition technique. No quasi-free charge-exchange background has been subtracted, following the assumption that the observed cross sections are primarily due to one-step charge-exchange leading to 1p–1h states of all multipolarities to all excitations. The theoretical shapes of the differential cross sections for each Jπ multipole have been taken from random-phase approximation (RPA)–distorted-wave impulse approximation (DWIA) calculations. The experimental dσ/dΩ, for each 1 MeV excitation-energy bin have been decomposed into different multipole components by a least squares fit. This RPA-based analysis should determine the Jπ = 1+ cross sections with different, and also fewer, assumptions than usual for describing the underlying background. It can be of general importance in determining the extent of possible quenching of Gamow–Teller (GT) strength. The present decomposition accounts for all the theoretically predicted GT strength. The purpose of the present report is to illustrate an analysis based on RPA–DWIA shapes rather than to present final-decomposition results.

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Cross section calculations for neutrino-nucleus reactions at low and intermediate energies.

HNPS Proceedings ◽

10.12681/hnps.2645 ◽

2020 ◽

Vol 15 ◽

pp. 249

Author(s):

V. Ch. Chasioti ◽

T. S. Kosmas ◽

P. Divari

Keyword(s):

Cross Sections ◽

Neutral Current ◽

Axial Vector ◽

Random Phase ◽

Neutrino Energy ◽

Reaction Cross ◽

Neutrino Experiment ◽

Final State ◽

Quasi Particle ◽

Intermediate Energies

Inelastic neutrino-nucleus reaction cross sections are studied focusing on the neutral current processes. Particularly, we investigate the angular and initial neutrino-energy dependence of the differential and integrated cross sections for low and intermediate energies of the incoming neutrino (or antineutrino). Contributions coming from both, the vector and axial-vector components of the corresponding hadronic currents have been included. The initial and final state nuclear wave-functions have been calculated in the context of the Quasi-particle Random Phase Approximation (QRPA) tested on the reproducibility of the low-lying energy spectrum (up to about 5 MeV) of the studied nuclei. The results presented here refer to the nuclear isotopes 16O and 98Mo. As it is well known, O plays a significant role in supernova evolution phenomena and Mo is used as a target in the MOON neutrino experiment at Japan.

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Charge Exchange Reactions in Astrophysical Plasmas

Symposium - International Astronomical Union ◽

10.1017/s0074180900093669 ◽

1983 ◽

Vol 103 ◽

pp. 187-197

Author(s):

R. McCarroll ◽

P. Valiron ◽

L. Opradolce

Keyword(s):

Charge Exchange ◽

Cross Sections ◽

Molecular Model ◽

Recent Experimental Data ◽

Exchange Reactions ◽

Astrophysical Plasmas ◽

Atomic Collisions ◽

Physical Conditions ◽

Theoretical Approaches ◽

Basic Features

A review is presented of charge exchange reactions of multiply charged ions with atomic hydrogen and helium at thermal-eV energies, typical of the physical conditions encountered in planetary nebulae. The basic features of the processes are analyzed in the framework of the molecular model of atomic collisions. A discussion is given of the different theoretical approaches to the calculation of the collision cross sections. A comparison with recent experimental data is included.

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Nuclear Structure Calculations for Two-Neutrino Double-βDecay

Advances in High Energy Physics ◽

10.1155/2016/6391052 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 4

Author(s):

P. Sarriguren ◽

O. Moreno ◽

E. Moya de Guerra

Keyword(s):

Charge Exchange ◽

Random Phase Approximation ◽

Random Phase ◽

Mean Field ◽

Experimental Information ◽

Exchange Reactions ◽

Quasiparticle Random Phase Approximation ◽

Nuclear Structure Calculations ◽

Structure Calculations ◽

Gamow Teller

We study the two-neutrino double-βdecay in76Ge,116Cd,128Te,130Te, and150Nd, as well as the two Gamow-Teller branches that connect the double-βdecay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed self-consistent mean field with Skyrme interactions including pairing and spin-isospin residual forces, which are treated in a proton-neutron quasiparticle random-phase approximation. We compare our results for Gamow-Teller strength distributions with experimental information obtained from charge-exchange reactions. We also compare our results for the two-neutrino double-βdecay nuclear matrix elements with those extracted from the measured half-lives. Both single-state and low-lying-state dominance hypotheses are analyzed theoretically and experimentally making use of recent data from charge-exchange reactions andβdecay of the intermediate nuclei.

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TO SEARCH FOR THE EXOTIC TENSOR MESON IN THE ρ+ρ+ AND ρ−ρ− CHANNELS IN HADRON COLLISIONS AT INTERMEDIATE ENERGIES

International Journal of Modern Physics A ◽

10.1142/s0217751x92001927 ◽

1992 ◽

Vol 07 (18) ◽

pp. 4313-4333 ◽

Cited By ~ 7

Author(s):

N.N. ACHASOV ◽

G.N. SHESTAKOV

Keyword(s):

Cross Sections ◽

Central Region ◽

Meson Production ◽

Pion Exchange ◽

Exchange Reactions ◽

Resonance States ◽

Tensor Meson ◽

Intermediate Energies ◽

The Cross

It is shown that reactions with one-pion exchange, reactions of meson production in the central region and reactions of nucleon-antinucleon annihilation can be good laboratories to search, in the ρ+ρ+ and ρ−ρ−channels, for the exotic resonance states E++ and E−− with IG(JP)=2+(2+), the signs of the neutral partner of which were discovered probably in the reactions γγ→ρρ. Detailed estimates are presented for the cross sections of the reactions π+p→E++n→ρ+ρ+n, π−ρ→E−−Δ++→ρ−ρ−∆++, ρρ→n(E++)n→n(ρ+ρ+)n and similar ones at intermediate energies.

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Neutral Mass-Selected Lead Cluster Beams

MRS Proceedings ◽

10.1557/proc-206-13 ◽

1990 ◽

Vol 206 ◽

Cited By ~ 1

Author(s):

M. Abshagen ◽

F. Träger ◽

J. Kowalski ◽

M. Meyberg ◽

G. zu Putlitz ◽

...

Keyword(s):

Charge Exchange ◽

Cross Sections ◽

Materials Science ◽

Metal Cluster ◽

Cluster Ions ◽

Universal Method ◽

Exchange Reactions ◽

Atomic Sodium ◽

D 12 ◽

Cluster Beams

ABSTRACTExperiments are described which illustrate that resonant neutralization of mass-selected cluster ions provides a universal method to produce neutral mass-selected metal cluster beams. Specifically, lead cluster ions, Pbn+ with n d 12, were neutralized by charge exchange reactions in atomic sodium and other target materials. Absolute charge exchange cross sections are on the order of 40 Å2 and up to 30% of the incident ions were neutralized. Possible fragmentation of the clusters associated with neutralization was investigated by translational spectroscopy. No indication of fragmentation was found for resonant electron transfer with atomic Na as target gas.. Thus, neutral metal cluster beams with ultra-narrow size distribution are produced. Deposition of such size-selected metal clusters on substrates opens new perspectives in materials science.

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