# Professor Jeff Tostevin

## Professor of Physics

Qualifications: BSc, PhD (1979, University of Surrey) CPhys, FInstP

Email:
Phone: Work: 01483 68 6784
Room no: 09 BB 03

## Biography

Jeff Tostevin is a theoretical nuclear physicist and a member of the Centre for Nuclear and Radiation Physics at Surrey. He has active research collaborations with colleagues at at Surrey and with theoretical and experimental physicists in the UK, the USA, Japan, and Europe. He joined the staff of the University of Surrey as a 'New Blood' lecturer in 1985. His particular research interests are the use of nuclear collisions and reactions to probe the structure of nuclei and to understand the reaction mechanisms and dynamics involved when nucleons and composite nuclei collide with a nuclear target.

## Research Interests

Jeff Tostevin is especially interested in the quantum mechanical and associated computational modelling of collisions of nucleons, loosely bound composite, exotic and unstable (neutron or proton rich) nuclear systems, their scattering and breakup, and also the dependence of these phenomena upon the spins of the nuclei and their constituents. He, with other Centre members, is pursuing research directed toward the greater understanding of the properties of nuclei away from the line of stable nuclei, taking opportunities provided by the recent production and use of high-intensity radioactive beams of exotic nuclei with unusual combinations of neutrons and protons.

## Research Collaborations

These are reflected in the publications list. Productive and long term collaborations are active with physicists at the National Superconducting Cyclotron Facility at Michigan State University, Florida State University and the Lawrence Berkeley National Laboratory in the USA, Tokyo Institute of Technology and RIKEN in Japan and with numerous European collaborators.

## Publications

### Highlights

• . (2011) 'Knockout Reactions from p-Shell Nuclei: Tests of Ab Initio Structure Models'. PHYSICAL REVIEW LETTERS, 106 (16) Article number ARTN 162502
• . (2010) 'Correlations probed in direct two-nucleon removal reactions'. PHYSICAL REVIEW C, 82 (4) Article number ARTN 044616
• . (2009) 'Mechanisms in Knockout Reactions'. PHYSICAL REVIEW LETTERS, 102 (23) Article number ARTN 232501
• . (2009) 'Two-Nucleon Knockout Spectroscopy at the Limits of Nuclear Stability'. PHYSICAL REVIEW LETTERS, 102 (13) Article number ARTN 132502

### Journal articles

• . (2014) 'Single-particle structure of silicon isotopes approaching 42Si'. Physical Review C: Nuclear Physics, 90 Article number 034301

#### Abstract

The structure of the neutron-rich silicon isotopes Si36,38,40 was studied by one-neutron and one-proton knockout reactions at intermediate beam energies. We construct level schemes for the knockout residues Si35,37,39 and Al35,37,39 and compare knockout cross sections to the predictions of an eikonal model in conjunction with large-scale shell-model calculations. The agreement of these calculations with the present experiment lends support to the microscopic explanation of the enhanced collectivity in the region of Si42. We also present an empirical method for reproducing the observed low-momentum tails in the parallel momentum distributions of knockout residues.

• . (2014) 'Mg19 two-proton decay lifetime'. Physical Review C: Nuclear Physics, 90 Article number 014301

#### Abstract

The ground state two-proton decay lifetime of Mg19, populated by the one-neutron knockout of an intermediate-energy Mg20 radioactive beam, was measured utilizing a new experimental technique. A thin silicon detector positioned at varying distances (0.0–1.0 mm) downstream of the reaction target measured the energy loss of Mg19 and the two-proton decay product Ne17. The lifetime was deduced from fits to the measured energy-loss line shapes and depended upon the contribution of prompt reaction processes to the yield of Ne17. For relative Ne17 prompt contributions from 82% to 92%, the extracted lifetimes ranged from 1.75+0.43−0.42 to 6.4+2.4−2.7 ps. The results are consistent with the previously reported Mg19 lifetime measurement and serve as both an important complementary study and a validation of this new technique, which can provide lifetime information for short-lived states beyond the proton drip line.

• . (2014) 'Observation of a p-Wave One-Neutron Halo Configuration in 37Mg'. Physical Review Letters, 112 Article number 242501

#### Abstract

Cross sections of 1n-removal reactions from the neutron-rich nucleus Mg37 on C and Pb targets and the parallel momentum distributions of the Mg37 residues from the C target have been measured at 240  MeV/nucleon. A combined analysis of these distinct nuclear- and Coulomb-dominated reaction data shows that the Mg37 ground state has a small 1n separation energy of 0.22+0.12−0.09  MeV and an appreciable p-wave neutron single-particle strength. These results confirm that Mg37 lies near the edge of the “island of inversion” and has a sizable p-wave neutron halo component, the heaviest such system identified to date.

• . (2014) 'Shell and shape evolution at N=28: The Mg40 ground state'. Physical Review C: Nuclear Physics, 89 Article number 041303

#### Abstract

A measurement of the direct two-proton removal from Si42 has provided the first structural information on the N=28 isotone Mg40. The value for the inclusive cross section for two-proton removal from Si42 of 40+27−17 μb is significantly lower than that predicted by structure calculations using the recent SDPF-MU shell-model effective interaction combined with eikonal reaction theory. This observed discrepancy is consistent with the interpretation that only one of the predicted low-lying 0+ states in Mg40 is bound. A two-state mixing analysis describing two-proton knockout cross sections along N=28 provides support for the interpretation of a prolate-deformed Mg40 ground state.

• . (2014) 'Deformation-driven p-wave Halos at the Drip-line: 31Ne'. Physical Review Letters, 112 Article number 142501

#### Abstract

The halo structure of Ne31 is studied using 1n-removal reactions on C and Pb targets at 230  MeV/nucleon. A combined analysis of the cross sections of these nuclear and Coulomb dominated reactions that feed directly the Ne30 ground-state reveals Ne31 to have a small neutron separation energy, 0.15+0.16−0.10  MeV, and spin-parity 3/2−. Consistency of the data with reaction and large-scale shell-model calculations identifies Ne31 as deformed and having a significant p-wave halo component, suggesting that halos are more frequent occurrences at the neutron drip line.

• . (2014) 'Nuclear Structure Towards N=40 Ca60: In-Beam γ-Ray Spectroscopy of Ti58,60'. Physical Review Letters, 112 Article number 112503

#### Abstract

Excited states in the neutron-rich N=38, 36 nuclei Ti60 and Ti58 were populated in nucleon-removal reactions from V61 projectiles at 90  MeV/nucleon. The γ-ray transitions from such states in these Ti isotopes were detected with the advanced γ-ray tracking array GRETINA and were corrected event by event for large Doppler shifts (v/c∼0.4) using the γ-ray interaction points deduced from online signal decomposition. The new data indicate that a steep decrease in quadrupole collectivity occurs when moving from neutron-rich N=36, 38 Fe and Cr toward the Ti and Ca isotones. In fact, Ti58,60 provide some of the most neutron-rich benchmarks accessible today for calculations attempting to determine the structure of the potentially doubly magic nucleus Ca60.

• . (2014) 'Intermediate energy four-body breakup calculations for 22C'. Physical Review C: Nuclear Physics, 89 (3) Article number 034607

#### Abstract

The heaviest particle-bound carbon isotope, C22, is thought to have a Borromean three-body structure. We discuss and compare four-body, i.e. three-body projectile plus target, reaction model calculations of reaction cross sections for such systems that use the fast adiabatic approximation. These methods are efficient and well-suited for quantitative analyses of reactions of neutron-rich nuclei with light target nuclei at secondary beam energies of ≈300 MeV/nucleon, as are now becoming available. We compare the predictions of the adiabatic model of the reaction both without and when including the additional eikonal approximation that has been used extensively. We show that the reaction cross section calculations have only limited sensitivity to the size and structure of C22 and that the differences arising from use of the eikonal approximation of the reaction mechanism are of a similar magnitude.

• . (2013) 'Mirror Energy Differences at Large Isospin Studied through Direct Two-Nucleon Knockout'. Physical Review Letters, 111 (7) Article number 072501

#### Abstract

The first spectroscopy of excited states in 52Ni (Tz=-2) and 51Co (Tz=-3/2) has been obtained using the highly selective two-neutron knockout reaction. Mirror energy differences between isobaric analogue states in these nuclei and their mirror partners are interpreted in terms of isospin nonconserving effects. A comparison between large-scale shell-model calculations and data provides the most compelling evidence to date that both electromagnetic and an additional isospin nonconserving interactions for J=2 couplings, of unknown origin, are required to obtain good agreement.

• . (2013) 'Rapid convergence of the Weinberg expansion of the deuteron stripping amplitude'. Physical Review C: Nuclear Physics, 87 (6) Article number 064613

#### Abstract

Theories of (d,p) reactions frequently use a formalism based on a transition amplitude that is dominated by the components of the total three-body scattering wave function where the spatial separation between the incoming neutron and proton is confined by the range of the n-p interaction, Vnp. By comparison with calculations based on the continuum discretized coupled channels method we show that the (d,p) transition amplitude is dominated by the first term of the expansion of the three-body wave function in a complete set of Weinberg states. We use the 132Sn(d,p)133Sn reaction at 30 and 100 MeV as examples of contemporary interest. The generality of this observed dominance and its implications for future theoretical developments are discussed.

• . (2013) 'Two-proton removal from 44S and the structure of 42Si'. Physical Review C: Nuclear Physics, 87 (2) Article number 027601

#### Abstract

Newly published 42Si γ-ray spectra and a final-state-inclusive 42Si production cross section value, obtained in a higher-statistics intermediate-energy two-proton removal experiment from 44S, are considered in terms of the final-state-exclusive cross sections computed using proposed shell-model effective interactions for nuclei near N=28. Specifically, we give cross section predictions when using the two nucleon amplitudes of the two-proton overlaps 〈42Si(Jπ) | 44S〉 computed using the newly proposed sdpf-mu shell-model Hamiltonian. We show that these partial cross sections or their longitudinal momentum distributions should enable a less-tentative interpretation of the measured gamma-ray spectra and provide a more quantitative assessment of proposed shell-model Hamiltonians in this interesting and challenging region of the chart of nuclides.

• . (2012) 'One-neutron knockout from 51-55Sc'. European Physical Journal A: Hadrons and Nuclei, 48 (12) Article number 191

#### Abstract

Results are presented from a one-neutron knockout experiment at relativistic energies of $\approx 420 A$ MeV on 51-55Sc using the GSI Fragment Separator as a two-stage magnetic spectrometer and the MINIBALL array for gamma-ray detection. Inclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the contributions corresponding to knockout from the $\nu p_{1/2}$ , $\nu p_{3/2}$ , (L = 1 and $\nu f_{7/2}$ , $\nu f_{5/2}$ (L = 3 neutron orbitals. The observed L = 1 and L = 3 contributions are compared with theoretical cross-sections using eikonal knockout theory and spectroscopic factors from shell model calculations using the GXPF1A interaction. The measured inclusive knockout cross-sections generally follow the trends expected theoretically and given by the spectroscopic strength predicted from the shell model calculations. However, the deduced L = 1 cross-sections are generally 30-40% higher while the L = 3 contributions are about a factor of two smaller than predicted. This points to a promotion of neutrons from the $\nu f_{7/2}$ to the $\nu p_{3/2}$ orbital indicating a weakening of the N = 28 shell gap in these nuclei. While this is not predicted for the phenomenological GXPF1A interaction such a weakening is predicted by recent calculations using realistic low-momentum interactions $V_{low k}$ obtained by evolving a chiral N3LO nucleon-nucleon potential.

• . (2012) 'Microscopic two-nucleon overlaps and knockout reactions from 12C'. Physical Review C: Nuclear Physics, 86 (5) Article number 054609

#### Abstract

The nuclear structure dependence of direct reactions that remove a pair of like or unlike nucleons from a fast 12C projectile beam are considered. Specifically, we study the differences in the two-nucleon correlations present and the predicted removal cross sections when using p-shell shell-model and multi-ℏω no-core shell-model (NCSM) descriptions of the two-nucleon overlaps for the transitions to the mass A=10 projectile residues. The NCSM calculations use modern chiral two-nucleon and three-nucleon (NN+3N) interactions. The np-removal cross sections to low-lying T=0, 10B final states are enhanced when using the NCSM two-nucleon amplitudes. The calculated absolute and relative partial cross sections to the low-energy 10B final states show a significant sensitivity to the interactions used, suggesting that assessments of the overlap functions for these transitions and confirmations of their structure could be made using final-state-exclusive measurements of the np-removal cross sections and the associated momentum distributions of the forward traveling projectile-like residues.

• . (2012) 'Correlations in intermediate-energy two-proton removal reactions'. Physical Review Letters, 109 (20) Article number 202505

#### Abstract

We report final-state-exclusive measurements of the light charged fragments in coincidence with 26Ne residual nuclei following the direct two-proton removal from a neutron-rich 28Mg secondary beam. A Dalitz-plot analysis and comparisons with simulations show that a majority of the triple-coincidence events with two protons display phase-space correlations consistent with the (two-body) kinematics of a spatially correlated pair-removal mechanism. The fraction of such correlated events, 56(12)%, is consistent with the fraction of the calculated cross section, 64%, arising from spin S=0 two-proton configurations in the entrance-channel (shell-model) 28Mg ground state wave function. This result promises access to an additional and more specific probe of the spin and spatial correlations of valence nucleon pairs in exotic nuclei produced as fast secondary beams.

• . (2012) 'Projectile deformation effects on single-nucleon removal reactions'. Physical Review C: Nuclear Physics, 86 (5) Article number 054603

#### Abstract

We discuss intermediate-energy single-nucleon removal reactions from deformed projectile nuclei. The removed nucleon is assumed to originate from a given Nilsson model single-particle state and the inclusive cross sections, to all rotational states of the residual nucleus, are calculated. We investigate the sensitivity of both the stripping cross sections and their momentum distributions to the assumed size of the model space in the Nilsson model calculations and to the shape of the projectile and residue. We show that the cross sections for small deformations follow the decomposition of the Nilsson state in a spherical basis. In the case of large and prolate projectile deformations the removal cross sections from prolate-like Nilsson states, having large values for the asymptotic quantum number nz, are reduced. For oblate-like Nilsson states, with small nz, the removal cross sections are increased. Whatever the deformation, the residue momentum distributions are found to remain robustly characteristic of the orbital angular momentum decomposition of the initial state of the nucleon in the projectile.

• . (2012) 'One- and two-neutron removal reactions from the most neutron-rich carbon isotopes'. Physical Review C: Nuclear Physics, 86 (5) Article number 054604

#### Abstract

The structure of 19,20,22C has been investigated using high-energy (around 240 MeV/nucleon) one- and two-neutron removal reactions on a carbon target. Measurements were made of the inclusive cross sections and momentum distributions for the charged residues. Narrow momentum distributions were observed for one-neutron removal from 19C and 20C and two-neutron removal from 22C. Two-neutron removal from 20C resulted in a relatively broad momentum distribution. The results are compared with eikonal-model calculations combined with shell-model structure information. The neutron removal cross sections and associated momentum distributions are calculated for transitions to both the particle-bound and particle-unbound final states. The calculations take into account the population of the mass A−1 reaction residues A−1C and, following one-neutron emission after one-neutron removal, the mass A−2 two-neutron removal residues A−2C. The smaller contributions of direct two-neutron removal, that populate the A−2C residues in a single step, are also computed. The data and calculations are shown to be in good overall agreement and consistent with the predicted shell-model ground-state configurations and one-neutron overlaps with low-lying states in 18−21C. These suggest significant νs1/22 valence neutron configurations in both 20C and 22C. The results for 22C strongly support the picture of 22C as a two-neutron halo nucleus with a dominant νs1/22 ground-state configuration.

• . (2012) 'γ-ray spectroscopy of one-proton knockout from 45Cl'. Physical Review C: Nuclear Physics, 86 (4) Article number 047301

#### Abstract

The role of proton shell effects in the structure of the N=28 isotones 45Cl and 44S has been studied via one-proton knockout from 45Cl. We compare measured γ-ray intensities, inclusive and partial knockout cross sections, and the inclusive momentum distribution of outgoing 44S particles with shell-model and reaction-theory predictions. The strong population in this reaction of the recently identified 41+ state in 44S, identified through its subsequent γ-ray decay energy, makes a compelling case for a Jπ=3/2+ ground state in 45Cl.

• . (2012) 'Systematic study of p-shell nuclei via single nucleon knockout reactions'. Physical Review C: Nuclear Physics, 86 (2) Article number 024315

#### Abstract

A systematic investigation of the inclusive cross sections for single-nucleon knockout reactions from p-shell nuclei has been performed. A total of seven reactions were studied for projectiles with masses between A = 7 and 10, having a wide range of nucleon separation energies. Results were obtained for a range of incident beam energies and targets. These differences were found to have a minimal impact on the deduced cross sections. Experimental results were compared to theoretical predictions based on variational Monte Carlo (VMC) nuclear structure calculations, whose radial overlap functions and neutron and proton densities were included in the reaction description. These results are compared with the conventional model, developed for heavier nuclei, that uses shell-model and Hartree-Fock structure inputs. The VMC-based calculations agreed with the experimental data for several reactions where deeply bound nucleons are removed but does not describe some of the more weakly bound nucleon removal cases with comparable accuracy.

• . (2012) 'Reply to "Comment on 'Neutron knockout of Be-12 populating neutron-unbound states in Be-11' "'. PHYSICAL REVIEW C, 86 (1) Article number ARTN 019802
• . (2012) 'Proton and neutron knockout from 36Ca'. Physical Review C: Nuclear Physics, 85 (6) Article number 064612

#### Abstract

The cross sections for single-nucleon knockout from Ca-36 on a Be-9 target at 70 MeV/nucleon were measured to be sigma(exp)(-p) = 51.1 +/- 2.6 mb for proton knockout and sigma(exp)(-n) = 5.03 +/- 0.46 mb for neutron knockout. The spectroscopic factors and orbital angular momenta of the neutrons and protons removed from Ca-36, leading to bound A = 35 residues, were deduced by comparison of the experimental cross sections and longitudinal- momentum distributions to those calculated in an eikonal reaction theory, and found to be S(p, 1d(3/2)) = 0.79 +/- 0.04 and S(n, 2s(1/2)) = 0.23 +/- 0.02 (relative to independent-particle-model values and only including experimental contributions to the uncertainties). As found in previous knockout studies, the spectroscopic factor deduced for the deeply bound neutron was significantly reduced relative to shell-model calculations, a result at variance with dispersive optical model (DOM) extrapolations, which suggest a spectroscopic factor closer to 60% of the independent-particle-model value.

• . (2012) 'Probing elastic and inelastic breakup contributions to intermediate-energy two-proton removal reactions'. PHYSICAL REVIEW C, 85 (5) Article number ARTN 051603
• . (2012) 'Intermediate-energy inverse-kinematics one-proton pickup reactions on neutron-deficient f p-shell nuclei'. PHYSICAL REVIEW C, 85 Article number ARTN 014610

#### Abstract

Background: Thick-target-induced nucleon-adding transfer reactions onto energetic rare-isotope beams are an emerging spectroscopic tool. Their sensitivity to single-particle structure complements one-nucleon removal reaction capabilities in the quest to reveal the evolution of nuclear shell structure in very exotic nuclei. Purpose: Our purpose is to add intermediate-energy, carbon-target-induced one-proton pickup reactions to the arsenal of γ-ray-tagged direct reactions applicable in the regime of low beam intensities and to apply these for the first time to fp-shell nuclei. Methods: Inclusive and partial cross sections were measured for the 12C(48Cr,49Mn+γ)X and 12C(50Fe,51Co+γ)X proton pickup reactions at 56.7 and 61.2 MeV/nucleon, respectively, using coincident particle-γ spectroscopy at the National Superconducting Cyclotron Laboratory. The results are compared to reaction theory calculations using fp-shell-model nuclear structure input. For comparison with our previous work, the same reactions were measured on 9Be targets. Results: The measured partial cross sections confirm the specific population pattern predicted by theory, with pickup into high-ℓ orbitals being strongly favored, driven by linear and angular momentum matching. Conclusion: Carbon-target-induced pickup reactions are well suited, in the regime of modest beam intensity, to study the evolution of nuclear structure, with specific sensitivities that are well described by theory.

• . (2011) 'Neutron-unbound states in F-25,F-26'. PHYSICAL REVIEW C, 84 (3) Article number ARTN 037302
• . (2011) 'Triple configuration coexistence in S-44'. PHYSICAL REVIEW C, 83 (6) Article number ARTN 061305
• . (2011) 'Inverse-kinematics one-neutron pickup with fast rare-isotope beams'. PHYSICAL REVIEW C, 83 (5) Article number ARTN 054324
• . (2011) 'Neutron knockout of Be-12 populating neutron-unbound states in Be-11'. PHYSICAL REVIEW C, 83 (5) Article number ARTN 057304
• . (2011) 'Knockout Reactions from p-Shell Nuclei: Tests of Ab Initio Structure Models'. PHYSICAL REVIEW LETTERS, 106 (16) Article number ARTN 162502
• . (2011) 'Two-nucleon correlation effects in knockout reactions from C-12'. PHYSICAL REVIEW C, 83 (1) Article number ARTN 014605
• . (2011) 'Search for the 15Be ground state'. Physical Review C - Nuclear Physics, 84 (4)
• . (2010) 'Correlations probed in direct two-nucleon removal reactions'. PHYSICAL REVIEW C, 82 (4) Article number ARTN 044616
• . (2010) 'Differential isomeric ratios following two-proton knockout from Pb-208'. PHYSICAL REVIEW C, 82 (3) Article number ARTN 037602
• . (2010) 'Collectivity at N=50: Ge-82 and Se-84'. PHYSICAL REVIEW C, 81 (6) Article number ARTN 064326
• . (2010) 'Si-25 and S-29 studied via single neutron knockout reactions'. PHYSICAL REVIEW C, 81 (6) Article number ARTN 067303
• . (2010) 'Two-proton knockout from Mg-32: Intruder amplitudes in Ne-30 and implications for the binding of F-29,F-31'. PHYSICAL REVIEW C, 81 (4) Article number ARTN 041302
• . (2010) 'Population of positive-parity states in Sc-53 through one-proton knockout'. PHYSICAL REVIEW C, 81 (2) Article number ARTN 024301
• . (2010) 'Knockout reactions'. Nuclear Physics News, 20 (1), pp. 11-16.
• . (2009) 'Population of low-seniority isomeric states of Hg-206 by two-proton knockout reactions at relativistic energies'. PHYSICAL REVIEW C, 80 (6) Article number ARTN 064608
• . (2009) 'Four-body continuum-discretized coupled-channels calculations'. PHYSICAL REVIEW C, 80 (5) Article number ARTN 051601
• . (2009) 'Rotational and neutron-hole states in S-43 via the neutron knockout and fragmentation reactions'. PHYSICAL REVIEW C, 80 (3) Article number ARTN 037305
• . (2009) 'Mechanisms in Knockout Reactions'. PHYSICAL REVIEW LETTERS, 102 (23) Article number ARTN 232501
• . (2009) 'Longitudinal momentum distributions of the reaction residues following fast two-nucleon knockout reactions'. PHYSICAL REVIEW C, 79 (6) Article number ARTN 064621
• . (2009) 'Structure of Ti-55 from relativistic one-neutron knockout'. PHYSICS LETTERS B, 675 (1), pp. 22-27.
• . (2009) 'Selectivity of the one-neutron knockout reaction on Cl-45 and the collapse of the N=28 shell closure'. PHYSICAL REVIEW C, 79 (5) Article number ARTN 051303
• . (2009) 'Intermediate energy proton knockout to the "island of inversion" isotope Mg-31'. PHYSICAL REVIEW C, 79 (5) Article number ARTN 054306
• . (2009) 'Two-Nucleon Knockout Spectroscopy at the Limits of Nuclear Stability'. PHYSICAL REVIEW LETTERS, 102 (13) Article number ARTN 132502
• . (2009) 'One- and two-neutron removal from the neutron-rich carbon isotopes'. PHYSICAL REVIEW C, 79 (2) Article number ARTN 024616
• . (2008) 'Dissipative quantum dynamics in low-energy collisions of complex nuclei'. PHYSICAL REVIEW C, 78 (6) Article number ARTN 064604
• . (2008) 'Neutron decay spectroscopy of neutron-rich oxygen isotopes'. NUCLEAR PHYSICS A, 813 (3-4), pp. 199-211.
• . (2008) 'R-matrix and dynamical model calculations of three-body resonance decay widths'. PHYSICAL REVIEW C, 78 (5) Article number ARTN 054603
• . (2008) 'd(5/2) proton hole strength in neutron-rich (43)P: Shell structure and nuclear shapes near N=28'. PHYSICAL REVIEW C, 78 (1) Article number ARTN 011303
• . (2008) 'Structure of excited states in (21)Mg studied in one-neutron knockout'. PHYSICAL REVIEW C, 77 (6) Article number ARTN 064309
• . (2008) 'Four-body continuum-discretized coupled-channels calculations using a transformed harmonic oscillator basis'. PHYSICAL REVIEW C, 77 (6) Article number ARTN 064609
• . (2008) 'Reduction of spectroscopic strength: Weakly-bound and strongly-bound single-particle states studied using one-nucleon knockout reactions'. PHYSICAL REVIEW C, 77 (4) Article number ARTN 044306
• . (2008) 'Single-neutron knockout from intermediate energy beams of (30,32)Mg: Mapping the transition into the "island of inversion"'. PHYSICAL REVIEW C, 77 (1) Article number ARTN 014316
• . (2008) 'In-beam gamma-ray spectroscopy at the proton dripline: Al-23'. PHYSICS LETTERS B, 666 (3), pp. 218-221.
• . (2008) 'In-beam gamma-ray spectroscopy and inclusive two-proton knockout cross section measurements at N approximate to 40'. PHYSICAL REVIEW C, 77 (5) Article number ARTN 054306
• . (2008) 'Single-particle motion at large distances in 2N+core cluster systems near the drip line: a challenge for nuclear theory and experiment'. Journal of Physics: Conference Series, Stratford upon Avon, UK: 111 (1) Article number 012034

#### Abstract

There exists a class of nuclei that are obtained by adding one nucleon to a loosely-bound nucleon-core system, for example $^{12}$Be, $^9$C, $^{18}$Ne. For such nuclei, one-nucleon overlap integrals that represent single-particle motion can strongly differ from the standard ones due to the correlations between the two nucleons above the core. The possible non-standard overlap behaviour should be included in the interpretation of the experimental data derived from one nucleon removal reactions such as knockout, transfer and breakup, as well as the predictions of low-energy nucleon capture that leads to these nuclei. We investigate the non-standard behaviour within a three-body model and discuss the challenges associated with this problem.

• . (2007) 'Inverse-kinematics one-proton pickup with intermediate-energy beams: The (9)Be ((20)Ne,(21)Na+gamma)X reaction'. PHYSICAL REVIEW C, 76 (6) Article number ARTN 061302
• . (2007) 'Selective population and neutron decay of an excited state of O-23'. PHYSICAL REVIEW LETTERS, 99 (11) Article number ARTN 112501
• . (2007) 'Spectroscopy of Mg-36: Interplay of normal and intruder configurations at the neutron-rich boundary of the "Island of Inversion"'. PHYSICAL REVIEW LETTERS, 99 (7) Article number ARTN 072502
• . (2007) 'Relating breakup and incomplete fusion of weakly bound nuclei through a classical trajectory model with stochastic breakup'. PHYSICAL REVIEW LETTERS, 98 (15) Article number ARTN 152701
• . (2006) 'Diffraction dissociation contributions to two-nucleon knockout reactions and the suppression of shell-model strength'. PHYSICAL REVIEW C, 74 (6) Article number ARTN 064604
• . (2006) 'One-neutron knockout in the vicinity of the N=32 sub-shell closure: Be-9(Cr-57,Cr-56+gamma)X'. PHYSICAL REVIEW C, 74 (4) Article number ARTN 047302
• . (2006) 'Direct evidence for the onset of intruder configurations in neutron-rich Ne isotopes'. PHYSICS LETTERS B, 640 (3), pp. 86-90.
• . (2006) 'Shell structure at N=28 near the dripline: Spectroscopy of Si-42, P-43, and S-44'. PHYSICAL REVIEW C, 74 (3) Article number ARTN 034313
• . (2006) 'Cross-shell excitation in two-proton knockout: Structure of Ca-52'. PHYSICAL REVIEW C, 74 (2) Article number ARTN 021302
• . (2006) 'One-neutron knockout from Ni-57'. PHYSICAL REVIEW C, 74 (2) Article number ARTN 024304
• . (2006) 'Two-neutron knockout from neutron-deficient Ar-34, S-30, and Si-26'. PHYSICAL REVIEW C, 74 (2) Article number ARTN 021303
• . (2006) 'Origin of the main r-process elements'. AIP Conference Proceedings, 847, pp. 227-232.

#### Abstract

The r-process is supposed to be a primary process which assembles heavy nuclei from a photo-dissociated nucleon gas. Hence, the reaction flow through light elements can be important as a constraint on the conditions for the r-process. We have studied the impact of di-neutron capture and the neutron-capture of light (Z<10) elements on r-process nucleosynthesis in three different environments: neutrino-driven winds in Type II supernovae; the prompt explosion of low mass supernovae; and neutron star mergers. Although the effect of di-neutron capture is not significant for the neutrino-driven wind model or low-mass supernovae, it becomes significant in the neutron-star merger model. The neutron-capture of light elements, which has been studied extensively for neutrino-driven wind models, also impacts the other two models. We show that it may be possible to identify the astrophysical site for the main r-process if the nuclear physics uncertainties in current r-process calculations could be reduced.

• . (2006) 'Two-neutron capture reactions and the r process'. PHYSICAL REVIEW C, 74 (1) Article number ARTN 015802
• . (2006) 'Reduced neutron spectroscopic factors when using potential geometries constrained by Hartree-Fock calculations'. PHYSICAL REVIEW C, 73 (4) Article number ARTN 044608
• . (2006) 'Population of bound excited states in intermediate-energy fragmentation reactions'. PHYSICAL REVIEW C, 73 (4) Article number ARTN 044605
• . (2006) 'Structure of 12Be: intruder d-wave strength at N=8.'. Phys Rev Lett, United States: 96 (3)

#### Abstract

The breaking of the N=8 shell-model magic number in the 12Be ground state has been determined to include significant occupancy of the intruder d-wave orbital. This is in marked contrast with all other N=8 isotones, both more and less exotic than 12Be. The occupancies of the [FORMULA: SEE TEXT]orbital and the [FORMULA: SEE TEXT], intruder orbital were deduced from a measurement of neutron removal from a high-energy 12Be beam leading to bound and unbound states in 11Be.

• . (2006) 'Probing the shell model using nucleon knockout reactions'. Journal of Physics: Conference Series, 49 (1), pp. 21-26.
• . (2005) 'Polarization observables and spin-dependent distortion effects in single-nucleon knockout reactions'. PHYSICAL REVIEW C, 72 (4) Article number ARTN 044603
• . (2005) 'Three-body continuum discretization in a basis of transformed harmonic oscillator states'. PHYSICAL REVIEW C, 72 (2) Article number ARTN 024007
• . (2005) ''Magic' nucleus Si-42'. NATURE, 435 (7044), pp. 922-924.
• . (2005) 'Dynamical core deformation effects on single-nucleon knockout reactions at fragmentation beam energies'. PHYSICAL REVIEW C, 71 (6) Article number ARTN 064608
• . (2005) 'Knockout from Ar-46 : l=3 neutron removal and deviations from eikonal theory'. PHYSICAL REVIEW C, 71 (5) Article number ARTN 051301
• . (2005) 'Improved implementation of the transfer-to-the-continuum method for single-neutron knockout reactions and the validity of standard approximations'. PHYSICAL REVIEW C, 71 (4) Article number ARTN 044606
• . (2004) 'Correlated two-nucleon stripping reactions'. PHYSICAL REVIEW C, 70 (6) Article number ARTN 064602
• . (2004) 'Reduced occupancy of the deeply bound 0d(5/2) neutron state in Ar-32'. PHYSICAL REVIEW LETTERS, 93 (4) Article number ARTN 042501
• . (2004) 'Systematic extraction of spectroscopic factors from C-12(d,p)C-13 and C-13(p,d)C-12 reactions'. PHYSICAL REVIEW C, 69 (6) Article number ARTN 064313
• . (2004) 'Absolute spectroscopic factors from neutron knockout on the halo nucleus C-15'. PHYSICAL REVIEW C, 69 (5) Article number ARTN 054306
• . (2004) 'Study of Be-14 with core excitation'. NUCL PHYS A, 733 (1-2), pp. 53-66.
• . (2004) 'One-neutron knockout reactions on proton-rich nuclei with N=16'. PHYSICAL REVIEW C, 69 (3) Article number ARTN 034311
• . (2004) 'Proton removal from B-8, C-9, and C-12 on Si at 20-70 MeV/nucleon'. PHYSICAL REVIEW C, 69 (2) Article number ARTN 024612
• . (2003) 'Pre-asymptotic behavior of single-particle overlap integrals of non-Borromean two-neutron halos'. PHYSICAL REVIEW C, 68 (2) Article number ARTN 021601
• . (2003) 'New direct reaction: Two-proton knockout from neutron-rich nuclei'. PHYSICAL REVIEW LETTERS, 91 (1) Article number ARTN 012501
• . (2003) 'Spectroscopic factors measured in inclusive proton-knockout reactions on B-8 and C-9 at intermediate energies'. PHYSICAL REVIEW C, 67 (6) Article number ARTN 064301
• . (2003) 'Comment on "Experimental evidence of core modification in the near drip-line nucleus O-23"'. PHYS REV LETT, 90 (15) Article number 159201
• . (2003) 'Direct reactions with exotic nuclei'. ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE, 53, pp. 219-261.
• . (2002) 'Single-neutron removal reactions from C-15 and Be-11: Deviations from the eikonal approximation'. PHYSICAL REVIEW C, 66 (2) Article number ARTN 024607
• . (2002) 'Core excitation in Be-12'. NUCL PHYS A, 703 (3-4), pp. 593-602.
• . (2002) 'Absolute spectroscopic factors from nuclear knockout reactions'. PHYSICAL REVIEW C, 65 (6) Article number ARTN 061601
• . (2002) 'Higher-order and E2 effects in medium energy B-8 breakup'. PHYSICAL REVIEW C, 65 (6) Article number ARTN 064619
• . (2002) 'Effects of the in-medium NN interaction on total reaction and neutron removal cross sections'. PHYSICAL REVIEW C, 65 (4) Article number ARTN 044617
• . (2002) 'Single-neutron knockout from Si-34,Si-35 and S-37'. PHYSICAL REVIEW C, 65 (3) Article number ARTN 034318
• . (2002) 'Single-neutron knockout from 34,35Si and 37S'. Physical Review C - Nuclear Physics, 65 (3), pp. 343181-3431810.
• . (2001) 'Calculations of three-body observables in B-8 breakup'. PHYS REV C, 6302 (2) Article number 024617
• . (2001) 'Single-neutron knockout reactions: Application to the spectroscopy of C-16,C-17,C-19'. PHYSICAL REVIEW C, 63 (2) Article number ARTN 024613
• . (2001) 'Electromagnetic dissociation of 8B and the rate of the 7Be(p, γ)8B reaction in the sun'. Physical Review C - Nuclear Physics, 63 (6), pp. 658061-6580614.
• . (2001) 'Study of Si and S with single-neutron removal reactions'. Nuclear Physics A, 690 (1-3)

#### Abstract

Preliminary results of one-neutron removal reactions on the nuclei Si and S at the intersection of the 1s0d and 1p0f neutron shells are reported. Momentum distributions of the projectile residues have been measured at the National Superconducting Cyclotron Laboratory at Michigan State University. The populated final states in the neutron removal reactions could be resolved by measuring the γ rays from the de-excitation of bound states using a position-sensitive NaI(T1) array. Partial cross sections to specific final states have been deduced. A comparison of the cross sections in the reactions (Si,Si) and (S,S) shows differences that point to the influence of intruder configurations in the vicinity of Si.

• . (2000) 'Correlated scattering corrections to eikonal few-body models'. PHYSICAL REVIEW C, 62 (6) Article number ARTN 064608
• . (2000) 'Direct evidence for the breakdown of the N=8 shell closure in Be-12'. PHYS REV LETT, 85 (2), pp. 266-269.
• . (2000) 'One-neutron knockout from individual single-particle states of Be-11'. PHYSICAL REVIEW LETTERS, 84 (1), pp. 35-38.
• . (1999) 'Long-range interactions and artificial poles'. J PHYS G NUCL PARTIC, 25 (11), pp. 2189-2195.
• . (1999) 'Three-body effects in the (d,He-2) charge-exchange reaction'. PHYSICAL REVIEW C, 60 (2) Article number ARTN 027002
• . (1999) 'Reaction cross section calculations for deformed nuclei'. PHYSICAL REVIEW C, 59 (4), pp. 2309-2312.
• . (1999) 'Noneikonal calculations for few-body projectiles'. PHYSICAL REVIEW C, 59 (3), pp. 1560-1566.
• . (1999) 'Importance of Coulomb dissociation of the deuteron on nucleon production reactions'. PHYS REV C, 59 (3), pp. 1555-1559.
• . (1999) 'Calculations of reaction cross sections for C-19 at relativistic energies'. PHYS REV C, 59 (1), pp. R5-R8.
• . (1998) 'Spectroscopy of radioactive beams from single-nucleon knockout reactions: Application to the sd shell nuclei Al-25 and P-26,P-27,P-28'. PHYS REV LETT, 81 (23), pp. 5089-5092.
• . (1998) 'Coulomb breakup of two-neutron halo nuclei'. PHYS REV C, 58 (2), pp. 1337-1340.
• . (1998) 'Coulomb dissociation of light nuclei'. PHYS REV C, 57 (6), pp. 3225-3236.
• . (1998) 'Coulomb breakup of light composite nuclei'. PHYS LETT B, 424 (3-4), pp. 219-225.
• . (1998) 'Few-body calculations of proton-(6),He-8 scattering'. PHYSICAL REVIEW C, 57 (4), pp. 1846-1852.
• . (1998) 'Coulomb breakup of Be-11 and C-19'. PHYSICAL REVIEW C, 58 (2), pp. 1042-1051.
• . (1997) 'Elastic and quasielastic scattering of He-8 from C-12'. PHYSICAL REVIEW C, 56 (6), pp. R2929-R2933.
• . (1997) 'Symmetrisation in the semiclassical theory of Coulomb excitation'. NUCL PHYS A, 624 (3), pp. 299-304.
• . (1997) 'Elastic scattering of halo nuclei'. PHYS REV LETT, 79 (15), pp. 2771-2774.
• . (1997) 'Four-body adiabatic model applied to elastic scattering'. NUCL PHYS A, 624 (2), pp. 275-292.
• . (1997) 'How large are the halos of light nuclei?'. Nuclear Physics A, 616 (1-2)

#### Abstract

We present quantitative reaction cross section calculations for halo nuclei at high energy which retain the essential few-body correlations in such structures. Inclusion of these correlations leads to larger deduced halo radii. For three-body (n+n+core) projectiles, cross section measurements determine the rms hyperradius of the system and, given the core nucleus size, the projectile matter radius. The importance of finite range effects are estimated in the case of the lightest two-neutron-halo system He. Outstanding uncertainties are discussed.

• . (1997) 'Beyond the eikonal model for few-body systems'. PHYS REV C, 55 (3), pp. R1018-R1022.
• . (1996) 'Radii of halo nuclei from cross section measurements'. PHYSICAL REVIEW C, 54 (4), pp. 1843-1852.
• . (1996) 'Structure signatures in proton scattering from Li-9,Li-11'. PHYSICAL REVIEW C, 54 (4), pp. 1867-1876.
• . (1996) 'Quasielastic scattering of Li-9 on C-12'. PHYSICAL REVIEW C, 54 (3), pp. 1262-1266.
• . (1996) 'Sensitivity of reaction cross sections to halo nucleus density distributions'. PHYSICAL REVIEW C, 53 (6), pp. 3009-3013.
• . (1996) 'Mean field calculations of nucleon-nucleus scattering'. PHYSICAL REVIEW C, 53 (6), pp. 3022-3031.
• . (1996) 'Adiabatic treatment of final states in (p,d*) reactions'. PHYS REV C, 53 (6), pp. 2949-2957.
• . (1996) 'Matter radii of light halo nuclei'. PHYSICAL REVIEW LETTERS, 76 (21), pp. 3903-3906.
• . (1996) 'Quasielastic scattering of 9Li on 12C'. Physical Review C - Nuclear Physics, 54 (3), pp. 1262-1266.
• . (1995) 'SPIN DEPENDENCE OF THE SCATTERING OF PROTONS FROM HALO NUCLEI'. PHYSICAL REVIEW C, 51 (6), pp. 3283-3289.
• . (1995) 'EVALUATION OF AN EIKONAL MODEL FOR LI-11-NUCLEUS ELASTIC-SCATTERING'. NUCLEAR PHYSICS A, 581 (2), pp. 331-355.
• . (1995) 'Extended adiabatic treatments of breakup'. Genshikaku Kenkyu, 40, pp. 95-104.
• . (1994) 'VALIDITY OF LOCAL-DENSITY PRESCRIPTIONS FOR MICROSCOPIC CALCULATIONS OF PROTON-NUCLEUS ELASTIC-SCATTERING'. PHYSICAL REVIEW C, 50 (6), pp. 2995-3009.
• . (1994) 'EQUIVALENT LOCAL POTENTIALS TO MULTIPLE-SCATTERING CALCULATIONS OF NUCLEON-NUCLEUS SCATTERING'. PHYSICAL REVIEW C, 49 (2), pp. 1091-1098.
• . (1994) 'DYNAMIC POLARIZATION POTENTIAL FOR LI-11 SCATTERING'. PHYS REV C, 49 (1), pp. 386-390.
• . (1993) 'DEUTERON BREAKUP EFFECTS IN TRANSFER-REACTIONS USING A WEINBERG STATE EXPANSION METHOD'. PHYSICAL REVIEW C, 48 (3), pp. 1307-1317.
• . (1993) 'BINDING EFFECTS IN PROTON-NUCLEUS ELASTIC-SCATTERING'. PHYSICAL REVIEW C, 48 (1), pp. 351-356.
• . (1993) 'QUASI-ELASTIC SCATTERING OF LI-11 USING REALISTIC 3-BODY WAVE-FUNCTIONS'. PHYSICAL REVIEW C, 47 (4), pp. R1364-R1368.
• . (1992) 'MULTIPLE-SCATTERING THEORY OF PROTON ELASTIC-SCATTERING AT INTERMEDIATE ENERGIES'. PHYSICAL REVIEW C, 46 (1), pp. 279-297.
• . (1992) 'EFFECTS OF LI-6 EXCITATION IN ZN-64(D-], LI-6)NI-60 AT LOW ENERGIES'. PHYS REV C, 45 (6), pp. 2824-2835.
• . (1991) 'MULTIPLE-SCATTERING EFFECTS IN PROTON NUCLEUS ELASTIC-SCATTERING AT INTERMEDIATE ENERGIES'. PHYSICAL REVIEW C, 44 (5), pp. R1735-R1739.
• . (1990) 'ENHANCEMENT OF THE NEAR-SIDE COMPONENT IN QUASIADIABATIC CALCULATIONS OF THE ZN-66(D,P)ZN-67 REACTION'. PHYSICAL REVIEW C, 42 (6), pp. 2562-2572.
• . (1990) 'TENSOR INTERACTION EFFECTS IN THE HE-4(H-2,GAMMA)LI-6 CAPTURE REACTION'. PHYSICAL REVIEW C, 42 (4), pp. 1646-1651.
• . (1990) 'SINGLET CHANNEL COUPLING IN DEUTERON ELASTIC-SCATTERING AT INTERMEDIATE ENERGIES'. NUCLEAR PHYSICS A, 514 (4), pp. 649-681.
• . (1990) 'TREATMENT OF THE COULOMB INTERACTION IN MOMENTUM SPACE CALCULATIONS OF PROTON ELASTIC-SCATTERING'. PHYSICAL REVIEW C, 41 (6), pp. 2615-2619.
• . (1990) 'FULL FOLDING CALCULATIONS FOR PROTON-NUCLEUS ELASTIC-SCATTERING AT INTERMEDIATE ENERGIES'. PHYSICAL REVIEW C, 41 (5), pp. 2257-2262.
• . (1990) 'EFFECTS OF SINGLET BREAKUP ON DEUTERON ELASTIC-SCATTERING AT INTERMEDIATE ENERGIES'. PHYSICAL REVIEW C, 41 (3), pp. R806-R810.
• . (1989) 'NATURE OF THE AMPLITUDES MISSING FROM ADIABATIC DISTORTED-WAVE MODELS OF MEDIUM ENERGY (D,P) AND (P,D) REACTIONS'. NUCLEAR PHYSICS A, 505 (1), pp. 26-66.
• . (1989) '3-BODY TREATMENT OF THE FINAL-STATE IN THE (3HE,PP) REACTION ON MEDIUM-MASS NUCLEI'. PHYS REV LETT, 62 (2), pp. 133-136.
• . (1988) 'THE MOMENTUM-DEPENDENT TP TENSOR INTERACTION IN INTERMEDIATE-ENERGY DEUTERON SCATTERING'. JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, 14 (5), pp. L103-L108.
• . (1988) 'THE ADIABATIC APPROXIMATION OF DEUTERON BREAK-UP EFFECTS FOR TRANSFER-REACTIONS AT MEDIUM ENERGY'. JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, 14 (5), pp. L97-L102.
• . (1988) 'THE H-2(D,N)HE-3 REACTION AT VERY LOW ENERGIES'. JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, 14 (1), pp. L1-L6.
• . (1987) 'THE SN-116(D,P)SN-117 L =0 REACTION-MECHANISM AT INTERMEDIATE ENERGIES'. NUCLEAR PHYSICS A, 469 (3), pp. 445-466.
• . (1987) 'THE EFFECTS OF FAR-SIDE DOMINANCE ON THE J-DEPENDENCE OF THE MEDIUM ENERGY SN-116(D,P)SN-117 REACTION'. NUCLEAR PHYSICS A, 469 (3), pp. 467-479.
• . (1987) 'THE ORIGIN OF THE SPIN-DEPENDENCE OF LOW-ENERGY DEUTERON SCATTERING'. NUCLEAR PHYSICS A, 466 (2), pp. 349-370.
• . (1987) 'ANTISYMMETRIZATION CORRECTIONS IN DEUTERON ELASTIC-SCATTERING AND DEUTERON-INDUCED TRANSFER-REACTIONS'. NUCLEAR PHYSICS A, 465 (1), pp. 83-122.
• . (1987) 'The Si(d, p)Sn l=0 reaction mechanism at intermediate energies'. Nuclear Physics, Section A, 469 (3), pp. 445-466.

#### Abstract

We report measurements of the cross section, proton polarization, and deuteron vector (A) and tensor (A) analyzing powers for the S(d, p))Sn reaction to the 1 2 ground state of Sn at E = 79.0 MeV. The polarization was observed as the analyzing power in the time-reversed Sn(p, d)Sn reaction. Adiabatic model calculations of the deuteron elastic channel reveal significant D-wave breakup contributions to the elastic cross section. Satisfactory agreement with the transfer reaction data is nevertheless obtained using adiabatic calculations which include only S-wave breakup and the bound deuteron D-state. The influence of the deuteron spin-orbit distortions on the polarization and vector analyzing power is reduced through a combination of the effects of angular momentum mismatch and deuteron channel absorption. © 1987.

• . (1986) 'ANTISYMMETRIZATION CORRECTIONS TO 3-BODY MODELS OF DEUTERON STRIPPING REACTIONS'. PHYSICS LETTERS B, 182 (2), pp. 124-128.
• . (1986) 'IMPLICATIONS OF FAR-SIDE DOMINANCE FOR THE DISAGREEMENT BETWEEN DISTORTED-WAVE THEORY AND WELL-MATCHED INTERMEDIATE ENERGY (D, P) REACTIONS'. PHYSICS LETTERS B, 171 (4), pp. 358-362.
• . (1986) 'H2(d,)He4 reaction and the He4 D state'. Physical Review C, 34 (4), pp. 1497-1500.
• . (1985) 'THEORETICAL AND EMPIRICAL STATUS OF THE 2-DEUTERON ALPHA-PARTICLE VERTEX'. JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, 11 (11), pp. L211-L217.
• . (1985) 'He4 D-state effects in the H2(d,) 4He reaction'. Physical Review C, 31 (2), pp. 707-709.
• . (1985) 'SEPARATION OF PROJECTILE AND EJECTILE SPIN-ORBIT DISTORTIONS IN AN L=0 (D, HE-3) REACTION'. NUCLEAR PHYSICS A, 436 (1), pp. 125-138.
• . (1984) 'PROJECTILE EXCITATION EFFECTS ON VECTOR POLARIZED LI-6 SCATTERING FROM SI-28 AND O-16'. PHYSICS LETTERS B, 138 (4), pp. 253-256.
• . (1984) 'DIRECT OBSERVATION OF THE ALPHA-PARTICLE D-STATE IN THE (D,ALPHA) REACTION'. PHYSICS LETTERS B, 149 (1-3), pp. 9-12.
• . (1984) 'PROJECTILE EXCITATION AND STRUCTURE EFFECTS IN LI-6 AND LI-7 SCATTERING'. NUCLEAR PHYSICS A, 415 (2), pp. 230-270.
• . (1983) 'Deformation effects in aligned Li scattering'. Physics Letters B, 124 (1-2), pp. 17-20.

#### Abstract

A second rank tensor potential for Li scattering is obtained within the framework of a single folding model by assuming an α + d cluster structure for Li. The intercluster wavefunction contains D-state and S-state components with amplitudes chosen to reproduce the experimental value of the Li Q-moment. Calculations are made for Li + Ni elastic scattering at E = 18.1 MeV. The puzzling behaviour of the measured tensor analysing power (T) is reproduced. © 1983.

• . (1983) 'ELECTRIC POLARIZABILITY OF THE DEUTERON AND THE NUCLEON-NUCLEON INTERACTION'. PHYS REV C, 28 (4), pp. 1779-1782.
• . (1983) '(D,ALPHA) REACTION AND THE ALPHA-PARTICLE D-STATE'. PHYS REV C, 28 (2), pp. 961-964.
• . (1983) 'ON THE SPIN-DEPENDENCE OF TRANSFER CHANNEL COUPLING IN SUB-COULOMB DEUTERON SCATTERING'. PHYSICS LETTERS B, 124 (3-4), pp. 135-138.
• . (1982) 'SPIN-ORBIT INTERACTION INDUCED BY HEAVY-ION PROJECTILE EXCITATION'. PHYSICAL REVIEW LETTERS, 48 (26), pp. 1795-1798.
• . (1982) 'DETERMINATION OF THE ASYMPTOTIC D-STATE TO S-STATE RATIO OF THE DEUTERON FROM SUB-COULOMB (D-],P) MEASUREMENTS'. PHYSICS LETTERS B, 118 (4-6), pp. 241-244.
• . (1981) 'EFFECT OF THE DEUTERON-TR TENSOR POTENTIAL ON THE DETERMINATION OF THE TRITON AND THE HE-3-D-STATE PARAMETER D2'. PHYSICS LETTERS B, 103 (4-5), pp. 259-263.
• . (1979) 'CORRECTIONS TO CONVENTIONAL SUB-COULOMB STRIPPING CALCULATIONS OF TENSOR ANALYZING POWERS'. PHYSICS LETTERS B, 85 (1), pp. 14-16.

### Conference papers

• . (2014) 'Calculations of Compound Nucleus Spin-parity Distributions Populated via the (p,t) Reaction in Support of Surrogate Reaction Measurements'. Elsevier Nuclear Data Sheets, 118

#### Abstract

The (p,t) transfer reaction is being studied for its potential use in surrogate reaction analyses. A theoretical model has been developed to predict spin-parity distributions of final states excited in the reaction. The model, after comparisons with experimental data, may provide a predictive capability to identify candidate isotopes for measurement. Preliminary results are presented for the 92Zr(p,t)90Zr reaction at incident proton energy Ep=28.5MeV. New experimental data for this reaction at a similar energy, and for several other stable Zr isotopes, will soon be available.

• . (2012) 'Probing the states of nucleons in exotic nuclei'. Journal of Physics Conference Series, Rutherford Centennial Conference on Nuclear Physics 381

#### Abstract

Many of the most exotic neutron-proton asymmetric nuclei are produced in relatively small numbers in high-energy fragmentation reactions. They are produced as fast secondary beams with energies of 100 MeV per nucleon or more. Developments made and recent results that both exploit and assess fast one- and two-nucleon removal reactions from such secondary beams are reviewed. This includes very recent work that interfaces the sudden, eikonal reaction models used with more ab-initio nuclear structure inputs. The potential use of neutron pick-up reactions to study particle-like states in exotic nuclei is also outlined.

• . (2011) 'Direct Reaction Probes of Single-Particle States and Correlations'. Progress of Theoretical Physics Supplement, Kyoto, Japan: Frontier Issues in Physics of Exotic Nuclei 196, pp. 275-282.

#### Abstract

The most exotic neutron-proton asymmetric nuclei are produced most efficiently in high-energy fragmentation reactions. These exotic nuclei are produced as fast secondary beams with energies of order 100 MeV per nucleon or greater, and hence v/c > 0.3, often with relatively low intensities. For such beams one can exploit both the detection efficiency and the cross sections for fast one- and two-nucleon removal reactions. The reaction dynamics of these channels is relatively simple due to the fast (sudden), surface grazing, and forward travelling (eikonal) nature of the reaction mechanism. More recent work now interfaces these sudden, eikonal reaction models with more microscopic nuclear structure model input. The possible roles of nucleon and pair correlations and their observation using such reaction data are discussed.

• . (2011) 'Three-body-model calculations for 22C'. Journal of Physics Conference Series, Rutherford Centennial Conference on Nuclear Physics 381

#### Abstract

There are now several well-studied instances where very neutron-rich light nuclei at or near the neutron drip-line, such as 6He, 11Li and 14Be, have been found to have a Borromean three-body structure. Such systems are modelled effectively as a well-bound core nucleus plus two weakly-bound valence neutrons, where none of the two-body subsystems forms a bound state. It is now known that the heaviest particle-bound carbon isotope, 22C, shares these properties. We discuss a development of four-body reaction model calculations, using the fast adiabatic approximation, that is particularly well-suited for a quantitative analysis of reactions of such neutron-rich nuclei with a target nucleus at beam energies of order 100-300 MeV per nucleon; energies available at new and future radioactive ion beam (RIB) facilities. The 22C projectile wave function is calculated using the 20C core plus two-valence neutron three-body description.

• . (2010) 'Four-body continuum-discretized coupled-channels calculations: Application to 6He+64Zn at 13.6 MeV'. American Institute of Physics AIP Conference Proceedings, LA RÁBIDA 2009, INTERNATIONAL SCIENTIFIC MEETING ON NUCLEAR PHYSICS: BASIC CONCEPTS IN NUCLEAR PHYSICS: THEORY, EXPERIMENTS AND APPLICATIONS 1231, pp. 235-236.

#### Abstract

The recently developed four-body continuum-discretized coupled-channels (CDCC) method, making use of the binning procedure [1], is applied to the reaction 6He+64Zn at 13.6 MeV (around the Coulomb barrier). Excellent agreement with available elastic data [2] is found.

• . (2009) 'Coupled-Channels Approach for Dissipative Quantum Dynamics in Near-Barrier Collisions'. AMER INST PHYSICS FUSION 08, Chicago, IL: International Conference on New Aspects of Heavy Ion Collisions Near the Coulomb Barrier 1098, pp. 44-51.

#### Abstract

A novel quantum dynamical model based on the dissipative quantum dynamics of open quantum systems is presented. It allows the treatment of both deep-inelastic processes and quantum tunneling (fusion) within a fully quantum mechanical coupled-channels approach. Model calculations show the transition from pure state (coherent) to mixed state (decoherent and dissipative) dynamics during a near-barrier nuclear collision. Energy dissipation, due to irreversible decay of giant-dipole excitations of the interacting nuclei, results in hindrance of quantum tunneling

• . (2007) 'Reaction spectroscopy at fragmentation beam energies - recent advances in studies of two-nucleon removal'. EDP SCIENCES S A EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS, Cortina, ITALY: 7th International Conference on Radioactive Nuclear Beams 150, pp. 67-70.
• . (2007) 'Continuum effects: Structure and reactions of He-6'. SPRINGER HEIDELBERG EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS, Cortina, ITALY: 7th International Conference on Radioactive Nuclear Beams 150, pp. 51-52.
• . (2007) 'Nuclear reactions used to probe the structure of nuclei far from stability'. ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS ACTA PHYSICA POLONICA B, Zakopane, POLAND: 41st Zakopane Conference on Nuclear Physics 38 (4), pp. 1195-1203.
• . (2006) 'Spectroscopy studies using two-nucleon knockout'. American Institute of Physics AIP Conference Proceedings, Univ Notre Dame, Notre Dame, IN: 12th International Symposium on Capture Gamma-Ray Spectroscopy and Related Topics 819, pp. 523-527.

#### Abstract

Two-proton removal reaction cross sections, from 208Pb at 1 GeV/nucleon, are estimated as an example of the direct population of (high-spin) seniority-2 isomeric states, here in 206Hg. Nucleon removal by both the stripping and diffractive mechanisms is considered. The cross sections in this specific (test) case are significant and can provide direct two-nucleon removal predictions of isomeric ratios

• . (2005) 'Coupled channels calculations of Be-11 breakup'. IOP PUBLISHING LTD JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, Univ Surrey, Guildford, ENGLAND: 1st International Conference on Nuclear, Structure, Astrophysics and Reactions (NUSTAR 05) 31 (10), pp. S1881-S1884.
• . (2005) 'Nuclear spectroscopy with fast exotic beams'. ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS ACTA PHYSICA POLONICA B, Zakopane, POLAND: 39th Zakopane School of Physics International Symposium 36 (4), pp. 1227-1233.
• . (2005) 'Nuclear spectroscopy with fast exotic beams'. IOP PUBLISHING LTD International Symposium on Correlation Dynamics in Nuclei, Univ Tokyo, Sanjo Kaikan, JAPAN: International Symposium on Correlation Dynamics in Nuclei 20, pp. 95-100.
• . (2005) 'Spectroscopic factors in exotic nuclei from nucleon-knockout reactions'. SPRINGER EUROPEAN PHYSICAL JOURNAL A, Pint Mt, GA: 4th International Conference on Exotic Nuclei and Atomic Masses 25, pp. 251-253.
• . (2005) 'Experimental evidence of a v(1d(5/2))(2) component to the Be-12 ground state'. SPRINGER EUROPEAN PHYSICAL JOURNAL A, Pint Mt, GA: 4th International Conference on Exotic Nuclei and Atomic Masses 25, pp. 349-351.
• . (2005) 'Evidence of a (1d(5/2))(2) component to the Be-12 ground state'. AMER INST PHYSICS Nuclei at the Limits, Argonne Natl Lab, Argonne, IL: Conference on Nuclei at the Limits 764, pp. 373-378.
• . (2004) 'Two-proton knockout on neutron-rich nuclei'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, Argonne, IL: 6th International Conference on Radioactive Nuclear Beams 746, pp. 173C-177C.
• . (2004) 'Direct reaction spectroscopy of exotic nuclei'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, Argonne, IL: 6th International Conference on Radioactive Nuclear Beams 746, pp. 166C-172C.
• . (2004) 'Threshold and continuum structures in exotic nuclei'. WORLD SCIENTIFIC PUBL CO PTE LTD NEW ERA OF NUCLEAR STRUCTURE PHYSICS, Kurokawa Village, JAPAN: International Symposiun on New Era of Nuclear Structure Physics, pp. 107-113.

#### Abstract

The role of continuum states in nuclei is considered, along with use of breakup theories of stripping and diffractive dissociation in probing nuclear structure. In the breakup of three-body nuclei such as Borromean halo systems, both three-body and two-body continuum final states need to be modelled and measured.

• . (2002) 'Coulomb breakup of B-8 and the flux of B-8 neutrinos from the Sun'. SPRINGER-VERLAG EUROPEAN PHYSICAL JOURNAL A, HAMEENLINNA, FINLAND: 3rd International Conference on Exotic Nuclei and Atomic Masses 15 (1-2), pp. 65-68.
• . (2002) 'Eikonal and coupled-channels reaction methods applied to studies of weakly bound nuclei'. PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT, KYOTO UNIV, YUKAWA INST THEORET PHYS, KYOTO, JAPAN: 10th Yukawa International Seminar on Physics of Unstable Nuclei (146), pp. 338-347.
• . (2002) 'Single-particle spectroscopy of rare isotope beams: Calculations beyond the eikonal approximation'. AMER INST PHYSICS NUCLEAR PHYSICS IN THE 21ST CENTURY, UNIV CALIF BERKELEY, BERKELEY, CA: International Nuclear Physics Conference 610, pp. 653-657.

#### Abstract

The momentum distributions of the residual nuclei after one-neutron removal, measured in coincidence with gamma rays, identify the excited levels of these residues. The resulting differential partial cross sections map the momentum content and structure of the removed-nucleon wave function and provide an exacting test of theory. Data for population of the C-14 and Be-10 ground states show an asymmetry that is incompatible with the currently used eikonal descriptions. A fully dynamical description of the elastic break-up mechanism provides an understanding of the new observation, which will be most pronounced for nuclear halo states, This interpretation is clarified by an analysis of the angular distribution of the heavy residues.

• . (2001) 'Multistep Coulomb and nuclear breakup of one-nucleon halo nuclei'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, DARMSTADT UNIV TECH, LICHTENBERG BLDG, DARMSTADT, GERMANY: International Symposium on Nuclei and Nucleons 690 (1-3), pp. 294C-297C.

#### Abstract

Coulomb dissociation of one neutron halo nuclei ‘IBe and 15,1QC has been studied at energies around 70A MeV by kinematically complete measurements of breakup particles at RIKEN. The experiment of l1Be breakup on a Pb target aims at studying the characteristic features of low-lying El strength. In particular the effects of higher order excitation and nuclear contribution have been closely studies by using the impact parameter analysis. We have found that these contributions are very small, and the selection of the large impact parameter is useful to extract the spectroscopic information of the halo ground state. We have then successfully applied this analysis method to l”C and “C, where we have extracted the spectroscopic factor for the s-wave halo configuration. We also show preliminary results on the breakup of “Be on a carbon target in order to study the nuclear breakup mechanism and low-lying discrete states of the halo nucleus.

• . (2001) 'Study of Si-34,Si-35 and S-37 With single-neutron removal reactions'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, DARMSTADT UNIV TECH, LICHTENBERG BLDG, DARMSTADT, GERMANY: International Symposium on Nuclei and Nucleons 690 (1-3), pp. 235C-238C.
• . (2001) 'One-nucleon knockout reactions: The test case C-15 and the single-particle structure of C-16,C-17,C-19'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, E LANSING, MICHIGAN: Conference on Nuclear Structure 2000 (NS2000) 682, pp. 332C-338C.
• . (2001) 'Single-nucleon knockout reactions at fragmentation beam energies'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, E LANSING, MICHIGAN: Conference on Nuclear Structure 2000 (NS2000) 682, pp. 320C-331C.
• . (1999) 'Coulomb break-up of halo nuclei within an adiabatic model'. IOP PUBLISHING LTD JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, LEWES, ENGLAND: International Conference on the Physics of Nuclear Structure at the Extremes 25 (4), pp. 851-853.
• . (1999) 'Core excitation in halo nucleus break-up'. IOP PUBLISHING LTD JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, LEWES, ENGLAND: International Conference on the Physics of Nuclear Structure at the Extremes 25 (4), pp. 735-739.
• . (1999) 'Single-particle structure of radioactive beams from one-nucleon knockout reactions'. AMER INST PHYSICS EXPERIMENTAL NUCLEAR PHYSICS IN EUROPE, SEVILLE, SPAIN: Conference on Experimental Nuclear Physics in Europe - Facing the Next Millennium (ENPE 99) 495, pp. 309-312.
• . (1999) 'Theory of nuclear reactions involving halo nuclei'. GIAHOUDI-GIAPOULI PUBLISHING PROCEEDINGS OF THE EUROPEAN CONFERENCE ON ADVANCES IN NUCLEAR PHYSICS AND RELATED AREAS, THESSALONIKI, GREECE: European Conference on Advances in Nuclear Physics and Related Areas, pp. 55-66.
• . (1998) 'Sizes and interactions of halo nuclei'. IOP PUBLISHING LTD JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS, PURI, INDIA: International Workshop on Physics with Radioactive Nuclear Beams 24 (8), pp. 1589-1597.
• . (1998) 'Manifestation of halo size in scattering and reactions'. ELSEVIER SCIENCE BV NUCLEAR PHYSICS A, GATLINBURG, TENNESSEE: 6th International Conference on Nucleus-Nucleus Collisions 630 (1-2), pp. 340C-351C.
• . (1998) 'Spectroscopy of Al-25 and P-26,P-27,P-28 using high-energy stripping reactions'. AMER INST PHYSICS ENAM 98: EXOTIC NUCLEI AND ATOMIC MASSES, BELLAIRE, MI: Conference on Exotic Nuclei and Atomic Masses (ENAM 98) 455, pp. 209-214.
• . (1998) 'Sizes of the He isotopes deduced from proton elastic scattering measurements'. AMER INST PHYSICS ENAM 98: EXOTIC NUCLEI AND ATOMIC MASSES, BELLAIRE, MI: Conference on Exotic Nuclei and Atomic Masses (ENAM 98) 455, pp. 227-232.
• . (1991) 'MODIFICATIONS OF THE EFFECTIVE ISOVECTOR INTERACTION FROM STUDIES OF ((P)RIGHT-ARROW,(P)RIGHT-ARROW') POLARIZATION TRANSFER'. PLENUM PRESS DIV PLENUM PUBLISHING CORP SPIN AND ISOSPIN IN NUCLEAR INTERACTIONS, TELLURIDE, CO: INTERNATIONAL CONF ON SPIN AND ISOSPIN IN NUCLEAR INTERACTIONS, pp. 281-286.

### Book chapters

• . (2013) 'Cooper pair correlations and energetic knock-out reactions'. in Broglia RA, Zelevinsky V (eds.) Fifty Years of Nuclear BCS World Scientific Publishing Company Article number 35

#### Abstract

Two-nucleon removal (or knock-out) reactions at intermediate energies are a developing tool for both nuclear spectroscopy and for the study of certain nucleon correlations in very exotic and some stable nuclei. We present an overview of these reactions with specific emphasis on the nature of the two-nucleon correlations that can be probed. We outline future possibilities and tests needed to fully establish these sensitivities.

• . (2001) 'Few-body models of nuclear reactions'. in Pike ER, Sabatier PC (eds.) Scattering Article number 3.1.3

## Teaching

Current teaching duties include courses in Mathematical and Computational Physics and small group tutorials at FHEQ Level 4 and Computational Modelling at FHEQ Level 5.

## Affiliations

Adjunct Professor, National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, USA.

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