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The dependence of the spin polarization on the incident angle of the primary beam has been measured for {sup 12}B fragments produced in the fragmentation of an {sup 18}O beam on a Nb target at 80 MeV/nucleon. A change in sign of the spin polarization was observed with a change in sign of the incident angle of the projectile. This result is in agreement with the kinematical model presented recently to qualitatively describe the mechanism for the production of spin-polarized fragments following intermediate-energy heavy-ion reactions. The resonance curve for {sup 12}B has also been measured using a technique of multiple adiabatic fast passage with continuous implantation. This technique is briefly compared to the single-pass adiabatic fast passage method employed with beam-on/beam-off data acquisition. {copyright} {ital 1997} {ital The American Physical Society}

Aims. Shape and spin state are basic physical characteristics of a n asteroid. They can be derived from disc-integrated photometry by the lightcurve inversion method. Increasing the number of asteroids with known basic physical properties is necessary to better understand the nature of individual objects as well as for studies of the whole asteroid population. Methods. We use the lightcurve inversion method to obtain rotation parameters and coarse shape models of selected asteroids. We combine sparse photometric data from the US Naval Observatory with ordinary lightcurves from the Uppsala Asteroid Photometric Catalogue and the Palmer Divide Observatory archive, and show that such combined data sets are in many cases suffi cient to derive a model even if neither sparse photometry nor lightcurves can be used alone. Our approach is tested on multiple-apparition lightcurve inversion models and we show that the method produces consistent results. Results. We present new shape models and spin parameters for 24 asteroids. The shape models are only coarse but describe the global shape characteristics well. The typical error in the pole directi on is∼ 10‐20 ◦ . For a further 18 asteroids, inversion led to a unique determination of the rotation period but the pole direction was not well constrained. In these cases we give only an estimate of the ecliptic latitude of the pole.

We observed ten M- and X-class main-belt asteroids with the Arecibo Observatory's S-band (12.6 cm) radar. The X-class asteroids were targeted based on their albedos or other properties which suggested they might be M-class. This work brings the total number of main-belt M-class asteroids observed with radar to 14. We find that three of these asteroids have rotation rates significantly different from what was previously reported. Based on their high radar albedo, we find that only four of the fourteen—16 Psyche, 216 Kleopatra, 758 Mancunia, and 785 Zwetana—are almost certainly metallic. 129 Antigone has a moderately high radar albedo and we suggest it may be a CH/CB/Bencubbinite parent body. Three other asteroids, 97 Klotho, 224 Oceana, and 796 Sarita have radar albedos significantly higher than the average main belt asteroid and we cannot rule out a significant metal content for them. Five of our target asteroids, 16 Psyche, 129 Antigone, 135 Hertha, 758 Mancunia, and 785 Zwetana, show variations in their radar albedo with rotation. We can rule out shape and composition in most cases, leaving variations in thickness, porosity, or surface roughness of the regolith to be the most likely causes. With the exception of 129 Antigone, we find no hydrated M-class asteroids (W-class; Rivkin, A.S., Howell, E.S., Lebofsky, L.A., Clark, B.E., Britt, D.T., 2000. Icarus 145, 351–368) to have high radar albedos.

International audience; Aims:We present physical models of ten asteroids obtained by means of lightcurve inversion. A substantial part of the photometric data was observed by amateur astronomers. We emphasize the importance of a coordinated network of observers that will be of extreme importance for future all-sky asteroid photometric surveys. Methods: The lightcurve inversion method was used to derive spin states and shape models of the asteroids. Results: We derived spin states and shape model for ten new asteroids: (110) Lydia, (125) Liberatrix, (130) Elektra, (165) Loreley, (196) Philomela, (218) Bianca, (306) Unitas, (423) Diotima, (776) Berbericia, and (944) Hidalgo. This increases the number of asteroid models up to nearly one hundred.

We have measured the parallel momentum distributions of outcoming fragments in the one-neutron breakup of the odd-mass carbon isotopes ${}^{19,17,15}\mathrm{C}$ and ${}^{14}\mathrm{B}$. Owing to their low neutron separation energies, the study of these nuclei is of particular interest regarding the appearance of the halo phenomenon. Discrepancies between experiment and theory observed for ${}^{15}\mathrm{C}$ and ${}^{14}\mathrm{B}$ indicate that their halos are not as prominent as in ${}^{11}$Be or ${}^{11}$Li, and that core excitations start playing a role in the breakup mechanism. In ${}^{17}\mathrm{C}$ the halo appears hindered by a $d$-wave neutron ground state configuration. Finally, the data on ${}^{19}\mathrm{C}$ suggests an $s$-wave neutron around the 2${}^{+}$ excited state in ${}^{18}\mathrm{C}$.

The $\ensuremath{\beta}$-unstable nuclei ${}^{32,34,36,38}\mathrm{Si}$ have been produced by projectile fragmentation and studied by in-beam Coulomb excitation. Excited states at $1399\ifmmode\pm\else\textpm\fi{}25$ keV and $1084\ifmmode\pm\else\textpm\fi{}20$ keV have been identified for the first time in ${}^{36}\mathrm{Si}$ and ${}^{38}\mathrm{Si}$, respectively, and tentatively assigned ${J}^{\ensuremath{\pi}}{\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2}^{+}$. The $B({E2;0}_{1}^{+}\ensuremath{\rightarrow}{2}_{1}^{+})$ values leading to these states and the previously identified ${2}_{1}^{+}$ states in ${}^{32,34}\mathrm{Si}$ have been measured, and are compared to shell model calculations. Our results indicate that the ${2}_{1}^{+}$ state in ${}^{34}\mathrm{Si}$ has a large $\mathrm{fp}$-shell intruder component, and that the ${2}_{1}^{+}$ states in the $Ng20$ silicon isotopes can be reproduced assuming an $N\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}20$ shell closure.

The proton scattering on unstable38S nuclei has been measured in inverse kinematics by using a38S secondary beam at 39 MeV/nucleon. The first 2+ state is seen at 1.2 MeV excitation energy and its angular distribution is extracted. Optical and folding model calculations are compared with the elastic and the 2 1 + angular distributions and the β2 value is determined to be 0.35±0.04. This value is compared with the corresponding result from a Coulomb excitation measurement and theM n/Mp value is extracted.

A 39A MeV {sup 38}S radioactive beam was used with inverse kinematics to measure angular distributions for elastic and inelastic proton scattering from a CH{sub 2} target. Optical potential and folding model calculations are compared with the elastic distribution. Using coupled channel calculations, the {beta}{sub 2} value for the 2{sub 1}{sup +} state is determined to be 0.35{plus_minus}0.04. This value, when compared with the corresponding result from a Coulomb excitation measurement, leads to M{sub n}/M{sub p}=(1.5{plus_minus}0.3) N/Z, indicating an isovector contribution to the 2{sub 1}{sup +} state of {sup 38}S. {copyright} {ital 1997} {ital The American Physical Society}

An exotic beam of {sup 11}Be at 57{endash}60 MeV/nucleon has been used for a study of the excitation cross section of the 320 keV first excited state in collisions with targets of Pb, Au, C, and Be. The deexcitation {gamma} rays were observed in an array of position-sensitive NaI(Tl) detectors in coincidence with the scattered fragment. The reduced transition strengths B(E1) extracted for the heavy targets suggest a predominantly electric excitation mechanism. Although the B(E1) value is marginally in agreement with that obtained from the lifetime of the state, the deviation is of the size expected from higher-order Coulomb and nuclear effects. Excitations on the lighter targets have sizable nuclear contributions. {copyright} {ital 1997} {ital The American Physical Society}

Elastic and inelastic scattering of protons on unstable 38 S nuclei has been measured in inverse kinematics by using a 38 S secondary beam at 39 MeV/nucleon. The excitation energy spectrum is measured up to 5 MeV. The first 2 + state is seen at 1.2 MeV excitation energy, and strength at around 3–5 MeV is also observed. Angular distributions for inelastic and elastic scattering are shown and compared to optical potential and folding model calculations. The preliminary β 2 value extracted for the first 2 + state is 0.38±0.05.

The first excited state of {sup 17}Ne has been populated via relativistic Coulomb excitation with a radioactive beam of {sup 17}Ne on a {sup 197}Au target and the subsequent {gamma}-ray decay has been observed. This (3)/(2){sup {minus}} state is bound with respect to proton emission but unbound to two-proton decay. The measured {gamma}-ray yield accounts for 43{sub {minus}14}{sup +19}{percent} of the predicted yield from an excitation cross section of 28 mb. It is unlikely that the missing cross section can be attributed to two-proton emission because the lifetime of this branch would have to be a factor 1700 smaller than predicted by standard barrier penetration calculations. {copyright} {ital 1997} {ital The American Physical Society}

We present the first AMS measurement of the 81Kr concentration in atmospheric krypton. The measurement was performed by combining positive-ion production in an electron cyclotron resonance source with acceleration to high energy in a cyclotron and subsequent full stripping for 81Br81Kr separation. The result, 81 Kr Kr = (5.3 ± 1.2) × 10 −13 , agrees well with two previous low-level decay counting measurements.

The energy and reduced transition probability B(E2; 0g.s.+ → 2+) for the lowest excited state in the neutron-rich isotope 1644S28 were measured by intermediate-energy Coulomb excitation. The excitation energy is E(2+) = 1297(18) keV and the reduced transition probability is B(E2; 0g.s.+ → 21+) = 314(88) e2fm4. The experimental results are compared with self-consistent mean-field calculations and shell model calculations with empirical interactions. The shell model calculations indicate that the large B(E2) value in 44S is vibrational in origin, while the neighboring isotopes 40,42S are statically deformed.

Distributions of parallel and transverse momenta for {sup 7}Be fragments formed in the breakup of {sup 8}B have been measured at 41A MeV. The {ital p}{sub {parallel}} distributions are narrow (81{plus_minus}4 and 62{plus_minus}3MeV/{ital c} FWHM for Be and Au targets, respectively), comparable to those of neutron halo nuclei. Reaction mechanisms influence the {sup 7}Be momentum distributions, so they do not directly reflect the valence proton momentum wave function. We present reaction models that reproduce the distributions. {copyright} {ital 1996 The American Physical Society.}

The {sup 1}H({sup 6}He,{sup 6}Li){ital n} reaction was studied at 0{degree} with the NSCL A1200 fragment separator in the energy loss mode. A {sup 6}He secondary beam at {ital E}/{ital A}=93 MeV was used to measure the Gamow-Teller and Fermi strengths between the ground state of {sup 6}He and the ground and excited states of {sup 6}Li, in inverse kinematics. At 0{degree} the ground-state cross section is measured to be {ital d}{sigma}{sub {ital GS}}/({ital d}{Omega})=43{plus_minus}16 mb/sr, which is dominated by systematic error in the secondary beam flux. The ratio of Gamow-Teller to Fermi strength is not sensitive to this error and is found to be (87{plus_minus}6){percent} of that expected from ({ital p},{ital n}) systematics and {beta} decay. Angular distributions have been measured between 0{degree} and 10{degree} in the center of mass. {copyright} {ital 1996 The American Physical Society.}

To gain a better understanding of the production of exotic isotopes and provide information on the stability of nuclei along the path of the rapid-proton capture process, isotopic cross sections from the reaction {sup 78}Kr + {sup 58}Ni at 75 MeV/nucleon were measured at 0{degree} using the A1200 fragment separator. Most notably the particle stability of {sup 69}Br was thoroughly probed during this experiment and it appears to be particle unstable. The experimental production cross section data are compared to previous krypton isotope fragmentation data to explore the dependence of the {ital N}/{ital Z} ratio of the projectile on the observed isotopic distributions ({open_quote}{open_quote}memory effect{close_quote}{close_quote}) as well as with an intranuclear cascade code developed for higher energies ({approx_gt} 200 MeV/nucleon) and a semiempirical parametrization derived from high energy systematics. {copyright} {ital 1996 The American Physical Society.}

An attempt was made to find the very neutron-rich isotope {sup 26}O among the fragmentation products of a 90 MeV/nucleon {sup 40}Ar beam. This isotope has been predicted to be bound but was not observed in a previous experiment by Guillemaud-Mueller {ital et} {ital al}. As part of the search, the momentum distributions of all the oxygen isotopes in the range from {sup 17}O to {sup 24}O were carefully determined so that the optimum separator setting for {sup 26}O could be used. From an extrapolation of the counting rates of the lighter oxygen isotopes, we expected to observe several hundred events of {sup 26}O during the measurement. However, no events could be attributed to {sup 26}O, thus indicating the particle instability of this isotope. The results for the production cross sections of 72 neutron-rich isotopes, ranging from {sup 38}P to {sup 11}B, are presented and compared to predictions. {copyright} {ital 1996 The American Physical Society.}

We have measured the longitudinal momentum distribution of ${}^{18}\mathrm{C}$, ${}^{17}\mathrm{C}$, and ${}^{16}\mathrm{C}$ after the one-neutron breakup of $^{19}C$, ${}^{18}\mathrm{C}$, and ${}^{17}\mathrm{C}$, respectively, using the A1200 fragment separator as an energy-loss spectrometer. The observed narrow width of $44.3\ifmmode\pm\else\textpm\fi{}5.9\mathrm{MeV}/c$ for the ${}^{18}\mathrm{C}$ fragments indicates that ${}^{19}\mathrm{C}$ is a new example of a one-neutron halo, so far the heaviest ever observed. The consequences of the obtained results on the structure of the three isotopes ${}^{19,18,17}\mathrm{C}$ are discussed together with shell-model calculations.

Total nuclear charge-changing cross sections σΔz in a CH2 target were measured for 54 isotopically identified secondary beams around A = 60 produced from a 1A·GeV86Kr beam via projectile fragmentation. With secondary beams between T z = 1 2 and −3, the isospin dependence of σΔz was investigated systematically. Contrary to the predictions of so-called overlap formulae, the σΔz values are not a function of the projectile mass alone, but are found to depend on the projectile isospin. A comparison of the data with the predictions of the statistical abrasion model reveals that this behaviour can be understood by the combined influence of the abrasion and the ablation phase in relativistic heavy-ion collisions. On the basis of this improved understanding, previous findings of anomalously large cross sections of secondary-reaction products are discussed.

Projectilelike residue yields and momentum distributions from the reaction of 70 MeV/nucleon [sup 86]Kr with [sup 27]Al at 0[degree] were studied. The data is compared with a model developed originally for higher energies ([gt]200 MeV/nucleon), data from prior experiments performed at both higher and lower bombarding energies, and a semiempirical parametrization derived from high energy systematics.

Cross sections of iridium and platinum isotopes have been measured, which were produced as fragments from 197 Au projectiles interacting with aluminum target nuclei at 1 A GeV. The fragments were identified by a kinematic analysis ( ΔE − Bρ -time-of-flight) and by an ion-optical separation at the projectile-fragment separator FRS at GSI. Indications are found for high excitation energies and weak proton-neutron correlations in the peripheral nuclear-collision process.

At the fragment separator FRS at GSI, relativistic secondary beams with nuclear mass numbers 50 ⩽ A ⩽ 62 were produced by the fragmentation of a 1 A ⊙ ot GeV 86 Kr beam in a 9 Be production target. The nuclear charge and mass numbers of the secondary-beam particles were determined by a Δ −t.o.f− Bϱ measurement. The fragmentation of stable and neutron-deficient manganese, iron, cobalt and nickel isotopes in a composite carbon-hydrogen target, placed behind the separator, was investigated. The element distributions of the secondary-fragmentation products were found to depend strongly on the neutron-to-proton ratio of the projectile. Calculations with a statistical abrasion model allow an explanation of the observed features by means of the different influences of the neutron-to-proton ratio of the projectile on the abrasion and ablation steps of the fragmentation r reaction.

The projectile-fragment separator FRS, recently installed at the heavy-ion synchrotron SIS18 at GSI, was used to measure the formation cross sections and longitudinal-momentum distributions of fragments produced by removing one, two or three protons from 0.8 GeV · A 136 Xe and 1 GeV · A 197 Au projectiles impinging on targets of beryllium and aluminum, respectively. These data gave direct information on the high-energy nuclear collision with only little contribution from evaporation processes. The measured cross sections decrease by more than one order of magnitude per proton removed. They are well reproduced by the predictions of a statistical abrasion model and an intranuclear-cascade calculation. The momentum distributions are found to be much broader than predicted by empirical systematics. They are, however, in agreement with the momentum distribution of the abraded protons as calculated with the uniform-Fermi-gas model, if Fermi momenta as measured by quasi-elastic electron scattering are used.

Nine new very neutron-deficient isotopes of Ag, Pd, Rh, and Ru have been identified among the reaction products of an [ital E]/[ital A]=60 MeV [sup 106]Cd beam using the A1200 projectile fragment separator at the National Superconducting Cyclotron Laboratory. One of these isotopes, [sup 94]Ag, is among the heaviest [ital N]=[ital Z] nuclei observed so far. The resulting mass spectra are presented and the astrophysical implications of the stability towards proton emission of one of the new isotopes, [sup 95]Ag, are discussed.

The mass of the nucleus $^{11}\mathrm{Li}$ has been determined from a measurement of the $Q$ value of the reaction $^{14}\mathrm{C}$($^{11}\mathrm{B}$,$^{11}\mathrm{Li}$)$^{14}\mathrm{O}$ at $\frac{E}{A}\ensuremath{\approx}32$ MeV. The results, which indicate a two-neutron separation energy of ${S}_{2n}(^{11}\mathrm{Li})=295\ifmmode\pm\else\textpm\fi{}35$ keV, put this basic quantity on a firm basis for use in theoretical models of the halo nucleus $^{11}\mathrm{Li}$.

The neutron-rich argon isotope ${}^{43}\mathrm{Ar}$ has been studied by quasielastic and inelastic proton scattering performed in inverse kinematics. The measured inelastic angular distribution for the second excited state is in good agreement with an $L=2$ transition. Assuming this transition to be $E2,$ yields a ${\ensuremath{\beta}}_{2}$ value for this state of $0.25\ifmmode\pm\else\textpm\fi{}0.03$ when compared with distorted-wave Born approximation calculations. This value is comparable to the one reported for the stable isotope ${}^{40}\mathrm{Ar}.$ Moreover it is similar to those measured by Coulomb excitation for the neighboring even-even isotopes ${}^{42}\mathrm{Ar}$ and ${}^{44}\mathrm{Ar}$ indicating that the structure of the argon isotopes is stable as a function of neutron number.

The availability of radioactive beams with relatively high intensities and good optical qualities makes possible the study of direct reactions induced by unstable nuclei. The problems of nuclear matter distributions, deformation and the modification of shell structure far from stability can be addressed through inverse kinematics reactions on light targets. The experimental method is presented and two examples in the case of the 38S (p,p′) and 40S (p,p′) reactions measured at the NSCL-MSU are given. Finally, the newly built silicon strip detector system, MUST, dedicated to such studies, is presented.

We have recently studied the structure of the neutron rich sulfur isotope 40S by using elastic and inelastic proton scattering in inverse kinematics. Optical potential and folding model calculations are compared with the elastic and inelastic angular distributions. Using coupled-channel calculations, the β2 value for the 21+ excited state is determined to be 0.35±0.05. The extracted value of Mn/Mp ratio indicates a small isovector contribution to the 21+ state of 40S. The microscopic analysis of the data is compatible with the presence of a neutron skin for this nucleus.

In order to map out a possible mass and isospin dependence of the effective charges in the sd-shell, we performed an intermediate energy Coulomb excitation experiment with the semi-magic, proton-rich nucleus 38Ca. The transition between the first excited state (21+, E*=2206 keV) and the ground state (0gs+) was studied, and the reduced transition strength and the proton transition matrix element were deduced. The nucleus 38Ca was chosen for this study, as it is at the upper mass end of the sd-shell, and will together with already existing high precision data for the lower mass end of the shell most clearly show a systematic trend in the effective charges. Our study also helps to fill the void of available high quality data for proton-rich nuclei in this mass region. We compare our data to theoretical shell model predictions with mass dependent, and mass independent effective charges, and to experimental values of the neutron-rich mirror nucleus 38Ar.

The (d,n) reaction of 7Be to form the ground state of 8B was studied in inverse kinematics using a 25 MeV/nucleon beam of 7Be nuclei from the A1200 fragment separator at the NSCL. The recoiling 8B nuclei were observed in a pair of position sensitive detector telescopes at lab angles between 1° and 5.5° (7° to 38° CMS). A large array of neutron detectors was placed at angles ranging from 158° to 104° (35° to 7° CMS) that measured the energy of coincident neutrons by their time-of-flight. The cross section for the d(7Be,8B)n reaction was determined from both the charged-particle singles and from the neutron coincidence data. In addition to measuring the transfer reaction, the quasi-elastic scattering of 7Be from deuterium was measured. The cross sections of these reactions are compared with DWBA and coupled-channels calculations.

We discuss the experimental situation of nucleon-induced reactions. Motivated by important current technological applications such as single event upsets (SEU) in microelectronic devices and particle-beam radiotherapy, we focus on light elements and beam energies below 250 MeV. We review the data from proton- and neutron-induced reactions obtained at UC Davis and elsewhere in the last 2 decades. Despite the large compilation of data (mainly inclusive spectra of light ions), we point out the scarcity of recoil data. We emphasize the fact that recoil nuclei contribute a significant part of the secondary radiation which is a major source of SEUs in devices, and of importance for radiation-related calculations. We discuss a new program under development, in which we measure recoil spectra using reverse kinematics. We discuss results from a recent experiment of 1H(28Si,A)x at 80 MeV/nucleon performed at the NSCL at Michigan State University. The preliminary data are compared well with a cascade-statistical reaction model (NUSPA).

A program directed towards the measurement of ground state moments in nuclei far from stability has been initiated at the National Superconducting Cyclotron Laboratory at Michigan State University. Spin-polarized fragments are produced at small angles relative to the primary beam axis by intermediate-energy heavy-ion reactions. The fragments are collected and analyzed using the A1200 fragment separator. The β-NMR technique is then used to detect the resonance frequency of the spin-polarized exotic fragments. The results of the first experiments using the β-NMR system recently installed at the NSCL will be reported, including measurements of the polarization of 12B fragments following the reaction of 18O at 80 MeV/A on a Nb target.

We explore the possibility of creating the light p‐nuclei 92Mo, 94Mo, 96Ru, and 98Ru through a rapid proton capture process. It is shown that for temperatures from 0.95×109 K to 1.4 × 109 K, significant abundances of these nuclides can be built up. Thorne‐Żytkow objects are suggested as possible sites for the process. The results are sensitive to the location of the proton drip‐line. In order to determine which proton rich nuclei in this mass range are proton bound, we analyzed the reaction products of an E/A=60 MeV 106Cd beam using the A1200 projectile fragment separator at the National Superconducting Cyclotron Laboratory. Nine new very neutron‐deficient isotopes of Ag, Pd, Rh, and Ru have been identified among them. The resulting mass spectra are presented.

A method for measuring the cross sections for the neutron removal from relativistic secondary projectiles by means of a two-stage magnetic spectrometer is presented. Its application to the 1n- and 2n-removal from 56 Ni and 52 Fe at 470 A ·MeV in an aluminum target is described. The results are compared to the intranuclear-cascade plus evaporation model and to the statistical abrasion-ablation model. The influence of the nuclear surface on the few-nucleon removal reactions is discussed. The neutron-removal cross sections are combined with total charge-changing cross sections to obtain the total interaction cross sections of 56 Ni and 52 Fe.

Differential cross sections have been measured near 0{degree} for the dominant channels in the mirror reaction {sup 13}C({sup 13}N,{sup 13}C){sup 13}N at {ital E}/{ital A}=57 and 105 MeV. The cross sections of the peaks in the excitation spectrum are discussed in terms of Gamow-Teller and Fermi transition strength. The cross section per unit Gamow-Teller strength is found to be enhanced relative to that for unit Fermi strength when compared with previous results from ({ital p},{ital n}) reactions. The present work represents the first use of a mirror-symmetric projectile and target system in a charge-exchange reaction as well as the first application of the developing radioactive nuclear beam field to this area. {copyright} {ital 1995 The American Physical Society.}

Elastic and inelastic proton scattering has been measured in inverse kinematics on the unstable nucleus ${}^{40}\mathrm{S}$. A phenomenological distorted wave Born approximation analysis yields a quadrupole deformation parameter ${\ensuremath{\beta}}_{2}=0.35\ifmmode\pm\else\textpm\fi{}0.05$ for the ${2}_{1}^{+}$ state. Consistent phenomenological and microscopic proton scattering analyses have been applied to all even-even sulfur isotopes from $A=32$ to $A=40$. The second analysis used microscopic collective model densities and a modified Jeukenne-Lejeune-Mahaux nucleon-nucleon effective interaction. This microscopic analysis suggests the presence of a neutron skin in the heavy sulfur isotopes. The analysis is consistent with normalization values for ${\ensuremath{\lambda}}_{v}$ and ${\ensuremath{\lambda}}_{w}$ of 0.95 for both the real and imaginary parts of the Jeukenne-Lejeune-Mahaux potential.