Search

The Low Energy Neutron Detector Array (LENDA) is a neutron time-of-flight (TOF) spectrometer developed at the National Superconducting Cyclotron Lab- oratory (NSCL) for use in inverse kinematics experiments with rare isotope beams. Its design has been motivated by the need to study the spin-isospin response of unstable nuclei using (p, n) charge-exchange reactions at intermediate energies (> 100 MeV/u). It can be used, however, for any reaction study that involves emission of low energy neutrons (150 keV - 10 MeV). The array consists of 24 plastic scintillator bars and is capable of registering the recoiling neutron energy and angle with high detection efficiency. The neutron energy is determined by the time-of-flight technique, while the position of interaction is deduced using the timing and energy information from the two photomultipliers of each bar. A simple test setup utilizing radioactive sources has been used to characterize the array. Results of test measurements are compared with simulations. A neutron energy threshold of < 150 keV, an intrinsic time (position) resolution of \sim 400 ps (\sim 6 cm) and an efficiency > 20 % for neutrons below 4 MeV have been obtained., Version accepted for publication in Nucl. Instr. Methods A. Revised text, 2 new figures added (one in section 4 and one in section 7)

Charge-exchange reactions at intermediate energies have been used extensively in nuclear structure studies as a sensitive probe of the spin-isospin response of nuclei. Experimental investigations have been mostly limited to stable targets. There are, however, compelling scientific arguments to extend these studies to unstable nuclei. The Low Energy Neutron Detection Array (LENDA) is designed to facilitate the study of (p,n) charge exchange reactions in inverse kinematics using unstable beams. The array, which is designed to measure neutron energies and angles with high detection efficiencies, is currently under development at the National Superconducting Cyclotron Laboratory (NSCL). The final array will consist of 24 plastic scintillator bars each with dimensions of 300 times 45 times 25 mm. The neutron energy will be determined by the time-of-flight technique, while the position of interaction will be deduced using the timing and energy information from photomultipliers attached to both ends of each bar. A prototype of the final array has been constructed and characterized in a simple test setup. Results of test measurements and simulations have demonstrated a neutron energy threshold of

Y. Fujita1,2 H. Fujita1 T. Adachi1 C.L. Bai3 A. Algora4,5 G.P.A. Berg6 P. von Brentano7 G. Colo8 M. Csatlos5 J.M. Deaven9 E. Estevez-Aguado4 C. Fransen7 D. De Frenne10 K. Fujita1 E. Ganioglu11 C.J. Guess9 J. Gulyas5 K. Hatanaka1 K. Hirota1 M. Honma12 D. Ishikawa1 E. Jacobs10 A. Krasznahorkay5 H. Matsubara1 K. Matsuyanagi13 R. Meharchand9 F. Molina4 K. Muto14 K. Nakanishi1 A. Negret15 H. Okamura1 H.J. Ong1 T. Otsuka16 N. Pietralla7 G. Perdikakis9 L. Popescu17 B. Rubio4 H. Sagawa13 P. Sarriguren18 C. Scholl7 Y. Shimbara19 Y. Shimizu1 G. Susoy11 T. Suzuki1 Y. Tameshige1 A. Tamii1 J.H. Thies20 M. Uchida1 T. Wakasa1 M. Yosoi1 R.G.T. Zegers1 K.O. Zell7 J. Zenihiro1

Y. Fujita et al.; 15 pags.; 6 figs.; 7 tabs.; PACS number(s): 21.10.Hw, 25.55.Kr, 27.40.+z, 25.40.Ep

Background: The Gamow-Teller response of $^{40}\mathrm{Ar}$ is important for the use of liquid argon as a medium for neutrino detection. An ambiguity about the Gamow-Teller strength for the excitation of ${1}^{+}$ states at 2290 and 2730 keV in $^{40}\mathrm{K}$ results in a significant uncertainty for neutrino capture rates. This ambiguity is caused by the large discrepancy observed between strengths extracted from $^{40}\mathrm{Ar}$($p$, $n$) charge-exchange data and the transition strengths for the analog transitions studied in the $\ensuremath{\beta}$ decay of $^{40}\mathrm{Ti}$.Purpose: This study was aimed at resolving the ambiguity between the results from the $^{40}\mathrm{Ar}$($p$, $n$) charge-exchange and $^{40}\mathrm{Ti}$ $\ensuremath{\beta}$-decay data.Method: Shell-model calculations in the $sd\text{\ensuremath{-}}pf$ shell with a new interaction (WBMB-C) were used to study differences between the structure of the transitions from $^{40}\mathrm{Ar}$ and $^{40}\mathrm{Ti}$. Distorted-wave Born approximation reaction calculations were used to investigate uncertainties in the extraction of Gamow-Teller strength from the $^{40}\mathrm{Ar}$($p$, $n$) data. New high-resolution data for the $^{40}\mathrm{Ar}$($^{3}\mathrm{He}$,$t$) reaction were used to gain further insight into the charge-exchange reaction mechanism and to provide more information to test the validity of the shell-model calculations.Results: The shell-model calculations showed that interference between amplitudes associated with $pf$ and $sd$ components to the low-lying Gamow-Teller transitions, in combination with a difference in Coulomb energy shifts for $^{40}\mathrm{Ar}$ and $^{40}\mathrm{Ti}$, can produce the differences on the scale of those observed between the $^{40}\mathrm{Ar}$ charge-exchange and $^{40}\mathrm{Ti}$ $\ensuremath{\beta}$-decay data. In combination with the difference in nuclear penetrability of the ($p$, $n$) and ($^{3}\mathrm{He}$,$t$) probes, the different contributions from amplitudes associated with transitions in the $pf$ and $sd$ shells are likely also responsible for the observed discrepancy between the ratio of the cross sections for the low-lying ${1}^{+}$ states in the $^{40}\mathrm{Ar}$($p$, $n$) and $^{40}\mathrm{Ar}$($^{3}\mathrm{He}$,$t$) data.Conclusions: On the basis of this study, it is recommended to use Gamow-Teller strengths extracted from the $^{40}\mathrm{Ar}$($p$, $n$) data, not the $^{40}\mathrm{Ti}$ $\ensuremath{\beta}$-decay data, for the calculation of neutrino capture rates. Further theoretical studies are required to achieve a consistent quantitative description for the energy differences between low-lying ${1}^{+}$ states in $^{40}\mathrm{K}$ and $^{40}\mathrm{Sc}$ and the experimentally observed Gamow-Teller strengths.

Y. Fujita et al. ; 5 pags. ; 3 figs. PACS numbers: 24.30.Cz, 25.55.Kr, 27.40.+z, Gamow-Teller (GT) transitions in atomic nuclei are sensitive to both nuclear shell structure and effective residual interactions. The nuclear GT excitations were studied for the mass number A=42, 46, 50, and 54 >f-shell> nuclei in (He3, t) charge-exchange reactions. In the Ca42→Sc42 reaction, most of the GT strength is concentrated in the lowest excited state at 0.6 MeV, suggesting the existence of a low-energy GT phonon excitation. As A increases, a high-energy GT phonon excitation develops in the 6-11 MeV region. In the Fe54→Co54 reaction, the high-energy GT phonon excitation mainly carries the GT strength. The existence of these two GT phonon excitations are attributed to the 2 fermionic degrees of freedom in nuclei. © 2014 American Physical Society., This work was in part supported by MEXT, Japan (Grants No. 13002001, No. 15540274, and No. 18540270); MICINN, Spain (Grant No. FPA200806419-C02-01). Y. F. and B. R. acknowledge the support of the Japan-Spain collaboration program by JSPS and CSIC.

In this work we have studied ${T}_{z}=+2\ensuremath{\rightarrow}+1$, Gamow-Teller (GT) transitions in the $^{48}\mathrm{Ti}(^{3}\mathrm{He},t)^{48}\mathrm{V}$ charge-exchange reaction at 140 MeV/nucleon and ${0}^{\ensuremath{\circ}}$ at the Research Center for Nuclear Physics, Osaka. From the high-resolution facility, consisting of a high-dispersion beamline and the Grand Raiden spectrometer, the spectrum had an energy resolution of 21 keV, among the best achieved. Individual GT transitions were observed and GT strength was derived for each state populated up to an excitation energy of 12 MeV. The total sum of the $B$(GT) strength observed in discrete states was 4.0, which is 33% of the sum-rule-limit value of 12. The results were compared with the results of shell-model calculations carried out with the GXPF1J interaction. The measured $B$(GT) distribution was also compared with that obtained in the $(^{3}\mathrm{He},t)$ charge-exchange reaction on $^{47}\mathrm{Ti}$. On the assumption of isospin symmetry the $\ensuremath{\beta}$ spectrum of the ${T}_{z}=\ensuremath{-}2$ nucleus $^{48}\mathrm{Fe}$ was deduced from the observed spectrum in the $^{48}\mathrm{Ti}(^{3}\mathrm{He},t)^{48}\mathrm{V}$ reaction and this predicted spectrum was compared with the measured one.

Background: Gamow-Teller (GT) transition strength distributions in stable and unstable $pf$-shell isotopes are key inputs for estimating electron-capture rates important for stellar evolution. Charge-exchange experiments at intermediate beam energies have long been used to test theoretical predictions for GT strengths, but previous experiments were largely restricted to stable nuclei. Since a large fraction of the nuclei relevant for astrophysical applications (including key nuclei such as ${}^{56}$Ni) are unstable, new methods are needed to perform charge-exchange experiments in inverse kinematics with unstable isotopes.Purpose: The ${}^{56}$Ni($p,n$) and ${}^{55}$Co($p,n$) reactions were measured in inverse kinematics in order to extract GT strengths for transitions to ${}^{56}$Cu and ${}^{55}$Ni, respectively. The extracted strength distributions were compared with shell-model predictions in the $pf$ shell using the KB3G and GXPF1J interactions. By invoking isospin symmetry, these strength distributions are relevant for electron captures on the ground states of ${}^{56}$Ni and ${}^{55}$Ni to final states in ${}^{56}$Co and ${}^{55}$Co, respectively.Method: Differential cross sections and excitation energy spectra for the ${}^{56}$Ni($p,n$) and ${}^{55}$Co($p,n$) reactions were determined by measuring neutrons recoiling from a liquid hydrogen target into the Low Energy Neutron Detector Array. GT contributions to the spectra were extracted by using a multipole decomposition analysis and were converted to strengths by employing the proportionality between GT strength and differential cross section at zero linear momentum transfer.Results: GT strengths from ${}^{56}$Ni and ${}^{55}$Co were extracted up to excitation energies of 8 and 15 MeV, respectively. Shell-model calculations performed in the $pf$ shell with the GXPF1J interaction reproduced the experimental GT strength distributions better than calculations with the KB3G interaction.Conclusions: A new technique for measuring ($p,n$) charge-exchange reactions on unstable nuclei was successfully developed. It can be used to study the isovector response of unstable nuclei in any mass region and for excitation energies beyond the particle decay threshold. In the first experiment, ${}^{56}$Ni($p,n$) and ${}^{55}$Co($p,n$) reactions were studied and GT transition strengths were extracted for the purpose of testing shell-model calculations used to estimate electron-capture rates in simulations of late stellar evolution. The calculation using the GXPF1J interaction was found to best reproduce the experimental strength distribution.

We report on the first experimental study of quadrupole collectivity in the very neutron-rich nuclei $^{47,48}\mathrm{Ar}$ using intermediate-energy Coulomb excitation. These nuclei are located along the path from doubly magic Ca to collective S and Si isotopes, a critical region of shell evolution and structural change. The deduced $B(E2)$ transition strengths are confronted with large-scale shell-model calculations in the sdpf shell using the state-of-the-art SDPF-Uand EPQQM effective interactions. The comparison between experiment and theory indicates that a shell-model description of Ar isotopes around $N=28$ remains a challenge.

We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller ($\ensuremath{\Delta}L=0$, $\ensuremath{\Delta}S=1$) transition strengths [$B(\mathrm{GT})$] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the $N=8$ shell gap. We populated the ground and 2.24 MeV ${0}^{+}$ states in $^{12}\mathrm{Be}$ using the $^{12}\mathrm{B}({1}^{+})$ ($^{7}\mathrm{Li}$, $^{7}\mathrm{Be}$) reaction at $80\text{ }\text{ }\mathrm{MeV}/u$ in inverse kinematics. Using the ground-state $B(\mathrm{GT})$ value from $\ensuremath{\beta}$-decay measurements ($0.184\ifmmode\pm\else\textpm\fi{}0.007$) as a calibration, the $B(\mathrm{GT})$ for the transition to the second ${0}^{+}$ state was determined to be $0.214\ifmmode\pm\else\textpm\fi{}0.051$. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second ${0}^{+}$ states in $^{12}\mathrm{Be}$ are composed of $25\ifmmode\pm\else\textpm\fi{}5%$ and $60\ifmmode\pm\else\textpm\fi{}5%$ $(0s{)}^{4}(0p{)}^{8}$ configurations, respectively.

A new technique to measure (p,n) charge-exchange reactions in inverse kinematics at intermediate energies on unstable isotopes was successfully developed and used to study the 56Ni(p,n) reaction at 110 MeV/u. Gamow-Teller transition strengths from 56Ni to 56Cu were obtained and compared with shell-model predictions in the pf-shell using the KB3G and GXPF1A interactions. The calculations with the GXPF1A interaction reproduce the experimental GT strength distribution much better than the calculations that employed the KB3G interaction, indicating deficiencies in the spin-orbit and proton-neutron residual potentials for the latter. The results are important for improving the description of electron-capture rates on nuclei in the iron region, which are important for modeling the late evolution of core-collapse and thermonuclear supernovae.

A new technique to measure (p,n) charge-exchange reactions in inverse kinematics at intermediate energies on unstable isotopes was successfully developed and used to study the (56)Ni(p,n) reaction at 110 MeV/u. Gamow-Teller transition strengths from (56)Ni leading to (56)Cu were obtained and compared with shell-model predictions in the pf shell using the KB3G and GXPF1A interactions. The calculations with the GXPF1A interaction reproduce the experimental strength distribution much better than the calculations that employed the KB3G interaction, indicating deficiencies in the spin-orbit and proton-neutron residual potentials for the latter. The results are important for improving the description of electron-capture rates on nuclei in the iron region, which are important for modeling the late evolution of core-collapse and thermonuclear supernovae.

The isomeric and $\ensuremath{\beta}$ decays of the $N=Z+2$ nucleus ${}^{96}\phantom{\rule{-0.16em}{0ex}}$Ag were investigated at the National Superconducting Cyclotron Laboratory. A cascade of $\ensuremath{\gamma}$-ray transitions originating from the deexcitation of a microsecond isomer was observed for the first time and was found in coincidence with two previously known transitions with energies of 470 and 667 keV. The isomeric half-life was determined as 1.45(7) $\ensuremath{\mu}$s, more precise than previously reported. The existence of a second, longer-lived microsecond isomer, associated with a 743-keV $\ensuremath{\gamma}$ transition, is also proposed here. Shell model results within the $({p}_{3/2}{p}_{1/2}{f}_{5/2}{g}_{9/2})$ model space, using the jj44b interaction, reproduced level energies and isomeric decay half-lives reasonably well.

The neutron-rich $N=28$ nucleus $^{44}\mathrm{S}$ was studied using the two-proton knockout reaction from $^{46}\mathrm{Ar}$ at intermediate beam energy. We report the observation of four new excited states, one of which is a strongly prolate deformed 4${}^{+}$ state, as indicated by a shell-model calculation. Its deformation originates in a neutron configuration which is fundamentally different from the ``intruder'' configuration responsible for the ground-state deformation. Consequently, we do not have three coexisting shapes in $^{44}\mathrm{S}$, but three coexisting configurations, corresponding to zero-, one-, and two-neutron particle-hole excitations.

The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{beta}{beta}) of {sup 150}Nd. The present results thus provide useful information on the neutrino responses for evaluating the 0{nu}{beta}{beta} and 2{nu}{beta}{beta} matrix elements. The 2{nu}{beta}{beta} matrix element calculated from the Gamow-Teller transitions through the lowest 1{sup +} state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2{nu}{beta}{beta} direct counting experiments, and at least several transitions through 1{sup +} intermediate states in {sup 150}Pm are required to explain the 2{nu}{beta}{beta} half-life. Because Gamow-Teller transitions in the {sup 150}Sm(t,{sup 3}He) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2({h_bar}/2{pi}){omega}, {Delta}L=0, {Delta}S=1 isovector spin-flipmore » giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.« less

The proportionality between differential cross sections at vanishing linear momentum transfer and Gamow-Teller transition strength, expressed in terms of the unit cross section (${\mathrm{\ensuremath{\sigma}\ifmmode \hat{}\else \^{}\fi{}}}_{\mathit{GT}}$), was studied as a function of target mass number for ($t$,$^{3}\mathrm{He}$) and ($^{3}\mathrm{He}$,$t$) reactions at $115A$ MeV and $140A$ MeV, respectively. Existing ($^{3}\mathrm{He}$,$t$) and ($t$,$^{3}\mathrm{He}$) data on targets with mass number $12\ensuremath{\leqslant}A\ensuremath{\leqslant}120$ were complemented with new and reevaluated ($t$,$^{3}\mathrm{He}$) data on proton, deuteron, $^{6}\mathrm{Li}$, and $^{12}\mathrm{C}$ targets. It was found that in spite of the small difference in beam energies between the two probes, the unit cross sections have a nearly identical and simple dependence on target mass number $A$, for $A\ensuremath{\geqslant}12$: ${\mathrm{\ensuremath{\sigma}\ifmmode \hat{}\else \^{}\fi{}}}_{\mathit{GT}}=109/{A}^{0.65}$. The factorization of the unit cross sections in terms of a kinematical factor, a distortion factor, and the strength of the effective spin-isospin transfer nucleus-nucleus interaction was investigated. Simple phenomenological functions depending on mass number $A$ were extracted for the latter two. By comparison with plane and distorted-wave Born approximation calculations, it was found that the use of a short-range approximation for knock-on exchange contributions to the transition amplitude results in overestimated cross sections for reactions involving the composite ($^{3}\mathrm{He}$,$t$) and ($t$,$^{3}\mathrm{He}$) probes.

The neutron-rich $N=50$ isotones $^{82}\mathrm{Ge}$ and $^{84}\mathrm{Se}$ were investigated using intermediate-energy Coulomb excitation on a $^{197}\mathrm{Au}$ target and inelastic scattering on $^{9}\mathrm{Be}$. As typical for intermediate-energy Coulomb excitation with projectile energies exceeding 70 MeV/nucleon, only the first ${2}^{+}$ states were excited in $^{82}\mathrm{Ge}$ and $^{84}\mathrm{Se}$. However, in the inelastic scattering on a $^{9}\mathrm{Be}$ target, a strong population of the first ${4}^{+}$ state was observed for $^{84}\mathrm{Se}$, while there is no indication of a similarly strong excitation of the corresponding state in the neighboring even-even isotone $^{82}\mathrm{Ge}$. The results are discussed in the framework of systematics and shell-model calculations using three different effective interactions.

We report on the first successful extraction of a ${\ensuremath{\beta}}^{+}$ Gamow-Teller strength distribution from a radioactive isotope in an intermediate-energy charge-exchange experiment in inverse kinematics. The ($^{7}\mathrm{Li},^{7}\mathrm{Be}+\ensuremath{\gamma}(429\text{ }\text{ }\mathrm{keV})$) reaction at $100A\text{ }\text{ }\mathrm{MeV}$ was used to measure Gamow-Teller transition strengths from $^{34}\mathrm{P}$ to states in $^{34}\mathrm{Si}$. The results show that little mixing occurs between $sd$ and $pf$ shell configurations for the low-lying ${0}^{+}$ and ${2}^{+}$ states even though $^{34}\mathrm{Si}$ neighbors the island of inversion and low-lying $2\ensuremath{\hbar}\ensuremath{\omega}$ intruder states exist. Shell-model calculations in the $sdpf$ model space are consistent with these findings.

Gamow-Teller and dipole transitions to final states in $^{13}\mathrm{B}$ were studied via the $^{13}\mathrm{C}(t,^{3}\mathrm{He})$ reaction at ${E}_{t}=115A$ MeV. In addition to the strong Gamow-Teller transition to the $^{13}\mathrm{B}$ ground state, a weaker Gamow-Teller transition to a state at 3.6 MeV was found. This state was assigned a spin-parity of $3/{2}^{\ensuremath{-}}$ by comparison with shell-model calculations using the WBP and WBT interactions which were modified to allow for mixing between $n\ensuremath{\hbar}\ensuremath{\omega}$ and $(n+2)\ensuremath{\hbar}\ensuremath{\omega}$ configurations. This assignment agrees with a recent result from a lifetime measurement of excited states in $^{13}\mathrm{B}$. The shell-model calculations also explained the relatively large spectroscopic strength measured for a low-lying $1/{2}^{+}$ state at 4.83 MeV in $^{13}\mathrm{B}$. The cross sections for dipole transitions up to ${E}_{x}$$(^{13}\mathrm{B})=20$ MeV excited via the $^{13}\mathrm{C}(t,^{3}\mathrm{He})$ reaction were also compared with the shell-model calculations. The theoretical cross sections exceeded the data by a factor of about 1.8, which might indicate that the dipole excitations are ``quenched''. Uncertainties in the reaction calculations complicate that interpretation.

The $^{24}\mathrm{Mg}(^{3}\mathrm{He},t){}^{24}$Al reaction was studied at $E({}^{3}\mathrm{He})=420$ MeV. An energy resolution of 35 keV was achieved. Gamow-Teller strengths to discrete levels in $^{24}\mathrm{Al}$ were extracted by using a recently developed empirical relationship for the proportionality between Gamow-Teller strengths and differential cross sections at zero momentum transfer. Except for small discrepancies for a few weak excitations, good agreement with previous $^{24}\mathrm{Mg}$($p,n$) data and nuclear-structure calculations using the USDA/B interactions in the $\mathit{sd}$ shell-model space was found. The excitation energy of several levels in $^{24}\mathrm{Al}$ of significance for determination of the $^{23}\mathrm{Mg}$${(p,\ensuremath{\gamma})}^{24}$Al thermonuclear reaction rate were measured. Results are consistent with two of the three previous ($^{3}\mathrm{He}$,$t$) measurements, performed at much lower beam energies. However, a new state at ${E}_{x}({}^{24}\mathrm{Al})=2.605(10)$ MeV was found and is the third state above the proton separation energy.

High resolution experimental data has been obtained for the 40,42,44,48Ca(3He,t)Sc charge exchange reaction at 420 MeV beam energy, which favors the spin-isospin excitations. The measured angular distributions were analyzed for each state separately, and the relative spin dipole strength has been extracted for the first time. The low-lying spin-dipole strength distribution in 40Sc shows some interesting periodic gross feature. It resembles to a soft, dumped multi-phonon vibrational band with $\hbar\omega$= 1.8 MeV, which might be associated to pairing vibrations around $^{40}$Ca.

First experimental evidence for a high-spin isomer ( 25 / 2 + ) in 97Cd, a waiting point in the astrophysical rapid proton capture process, is presented. The data were obtained in β-decay studies at NSCL using the new RF Fragment Separator system and detecting β-delayed protons and β-delayed γ rays. Decays from ground and isomeric states were disentangled, and proton emission branches were determined for the first time. We find half-lives of 1.10(8) s and 3.8(2) s, and β-delayed proton emission branches of 12(2)% and 25(4)% were deduced for the ground and isomeric states, respectively. With these results, the nuclear data needed to determine an rp-process contribution to the unknown origin of solar 96Ru are in place. When the new data are included in astrophysical rp-process calculations, one finds that an rp-process origin of 96Ru is unlikely.