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Monte Carlo simulations are widely used in nuclear physics to model experimental systems. In cases where there are significant unknown quantities, such as energies of states, an iterative process of simulating and fitting is often required to describe experimental data. We describe a Bayesian approach to fitting experimental data, designed for data from a $^{12}$Be(d,p) reaction measurement, using simulations made with GEANT4. Q-values from the $^{12}$C(d,p) reaction to well-known states in $^{13}$C are compared with simulations using BayesOpt. The energies of the states were not included in the simulation to reproduce the situation for $^{13}$Be where the states are poorly known. Both cases had low statistics and significant resolution broadening owing to large proton energy losses in the solid deuterium target. Excitation energies of the lowest three excited states in $^{13}$C were extracted to better than 90 keV, paving a way for extracting information on $^{13}$Be., 8 pages, 6 figures

15O(α,γ)19Ne is regarded as one of the most important thermonuclear reactions in type I X-ray bursts. For studying the properties of the key resonance in this reaction using β decay, the existing Proton Detector component of the Gaseous Detector with Germanium Tagging (GADGET) assembly is being upgraded to operate as a time projection chamber (TPC) at FRIB. This upgrade includes the associated hardware as well as software and this paper mainly focusses on the software upgrade. The full detector set up is simulated using the ATTPCROOTv 2 data analysis framework for 20Mg and 241Am.

Sensitivity studies have shown that the 15O(α, γ)19Ne reaction is the most important reaction rate uncertainty affecting the shape of light curves from Type I X-ray bursts. This reaction is dominated by the 4.03 MeV resonance in 19Ne. Previous measurements by our group have shown that this state is populated in the decay sequence of 20Mg. A single 20Mg(βp α)15O event through the key 15O(α, γ)19Ne resonance yields a characteristic signature: the emission of a proton and alpha particle. To achieve the granularity necessary for the identification of this signature, we have upgraded the Proton Detector of the Gaseous Detector with Germanium Tagging (GADGET) into a time projection chamber to form the GADGET II detection system. GADGET II has been fully constructed, and is entering the testing phase.

At temperatures below 0.1 GK, the $^{19}\mathrm{F}(p,\ensuremath{\gamma})^{20}\mathrm{Ne}$ reaction is the only breakout path out of the CNO cycle. Experimental studies of this reaction are challenging from a technical perspective due to copious $\ensuremath{\gamma}$-ray background from the far stronger $^{19}\mathrm{F}(p,\ensuremath{\alpha})^{16}\mathrm{O}$ reaction channel. Here, we present the first inverse kinematics study of the $^{19}\mathrm{F}(p,\ensuremath{\gamma})^{20}\mathrm{Ne}$ reaction, in which we measure the strength of the 323-keV resonance. We find a strength value of $\ensuremath{\omega}\ensuremath{\gamma}=3.{3}_{\ensuremath{-}0.9}^{+1.1}$ meV, which is a factor of two larger than the most recent previous study. The discrepancy is likely the result of a direct to ground state transition which previous studies were not sensitive to. We also observe the transition to the first ${2}^{\ensuremath{-}}$ state, which has not been observed for this resonance in previous studies. A new thermonuclear reaction rate is calculated and compared with the literature.

Gamma-Ray Infrastructure For Fundamental Investigations of Nuclei, GRIFFIN, is a new high-efficiency γ -ray spectrometer designed for use in decay spectroscopy experiments with low-energy radioactive ion beams provided by TRIUMF’s Isotope Separator and Accelerator (ISAC-I) facility. GRIFFIN is composed of sixteen Compton-suppressed large-volume clover-type high-purity germanium (HPGe) γ -ray detectors combined with a suite of ancillary detection systems and coupled to a custom digital data acquisition system. The infrastructure and detectors of the spectrometer as well as the performance characteristics and the analysis techniques applied to the experimental data are described.

Objective Cricothyrotomy is a complex procedure with a high rate of complications including failure to cannulate and injury to adjacent anatomy. The Control-Cric™ System and QuickTrach II™ represent two novel devices designed to optimize success and minimize complications with this procedure. This study compares these two devices against a standard open surgical technique. Methods We conducted a randomized crossover study of United States Army combat medics using a synthetic cadaver model. Participants performed a surgical cricothyrotomy using the standard open surgical technique, Control-Cric™ System, and QuickTrach II™ device in a random order. The primary outcome was time to successful cannulation. The secondary outcome was first-attempt success. We also surveyed participants after performing the procedures as to their preferences. Results Of 70 enrolled subjects, 65 completed all study procedures. Of those that successfully cannulated, the mean times to cannulation were comparable for all three methods: standard 51.0 s (95% CI 45.2–56.8), QuickTrach II™ 39.8 s (95% CI 31.4–48.2) and the Cric-Control™ 53.6 (95% CI 45.7–61.4). Cannulation failure rates were not significantly different: standard 6.2%, QuickTrach II™ 13.9%, Cric-Control™ 18.5% (p = 0.106). First pass success rates were also similar (93.4%, 91.1%, 88.7%, respectively, p = 0.670). Of respondents completing the post-study survey, a majority (52.3%) preferred the QuickTrach II™ device. Conclusions We identified no significant differences between the three cricothyrotomy techniques with regards to time to successful cannulation or first-pass success.

Background: Globular clusters are known to exhibit anomalous abundance trends such as the sodium-oxygen anticorrelation. This trend is thought to arise via pollution of the cluster interstellar medium from a previous generation of stars. Intermediate-mass asymptotic giant branch stars undergoing hot bottom burning (HBB) are a prime candidate for producing sodium-rich oxygen-poor material, and then expelling this material via strong stellar winds. The amount of $^{23}\mathrm{Na}$ produced in this environment has been shown to be sensitive to uncertainties in the $^{22}\mathrm{Ne}(p,\ensuremath{\gamma})^{23}\mathrm{Na}$ reaction rate. The $^{22}\mathrm{Ne}(p,\ensuremath{\gamma})^{23}\mathrm{Na}$ reaction is also activated in classical nova nucleosynthesis, strongly influencing predicted isotopic abundance ratios in the Na-Al region. Therefore, improved nuclear physics uncertainties for this reaction rate are of critical importance for the identification and classification of pre-solar grains produced by classical novae.Purpose: At temperatures relevant for both HBB in AGB stars and classical nova nucleosynthesis, the $^{22}\mathrm{Ne}(p,\ensuremath{\gamma})^{23}\mathrm{Na}$ reaction rate is dominated by narrow resonances, with additional contribution from direct capture. This study presents new strength values for seven resonances, as well as a study of direct capture.Method: The experiment was performed in inverse kinematics by impinging an intense isotopically pure beam of $^{22}\mathrm{Ne}$ onto a windowless ${\mathrm{H}}_{2}$ gas target. The $^{23}\mathrm{Na}$ recoils and prompt $\ensuremath{\gamma}$ rays were detected in coincidence using a recoil mass separator coupled to a $4\ensuremath{\pi}$ bismuth-germanate scintillator array surrounding the target.Results: For the low-energy resonances, located at center of mass energies of 149, 181, and 248 keV, we recover stength values of $\ensuremath{\omega}{\ensuremath{\gamma}}_{149}=0.{17}_{\ensuremath{-}0.04}^{+0.05}, \ensuremath{\omega}{\ensuremath{\gamma}}_{181}=2.2\ifmmode\pm\else\textpm\fi{}0.4$, and $\ensuremath{\omega}{\ensuremath{\gamma}}_{248}=8.2\ifmmode\pm\else\textpm\fi{}0.7 \ensuremath{\mu}\text{eV}$, respectively. These results are in broad agreement with recent studies performed by the LUNA and TUNL groups. However, for the important reference resonance at 458 keV we obtain a strength value of $\ensuremath{\omega}{\ensuremath{\gamma}}_{458}=0.44\ifmmode\pm\else\textpm\fi{}0.02$ eV, which is significantly lower than recently reported values. This is the first time that this resonance has been studied completely independently from other resonance strengths. For the 632-keV resonance we recover a strength value of $\ensuremath{\omega}{\ensuremath{\gamma}}_{632}=0.48\ifmmode\pm\else\textpm\fi{}0.02$ eV, which is an order of magnitude higher than a recent study. For reference resonances at 610- and 1222-keV, our strength values are in agreement with the literature. In the case of direct capture, we recover an $S$ factor of 60 keV b, consistent with prior forward kinematics experiments.Conclusions: In summary, we have performed the first direct measurement of $^{22}\mathrm{Ne}(p,\ensuremath{\gamma})^{23}\mathrm{Na}$ in inverse kinematics. Our results are in broad agreement with the literature, with the notable exception of the 458-keV resonance, for which we obtain a lower strength value. We assessed the impact of the present reaction rate in reference to a variety of astrophysical environments, including AGB stars and classical novae. Production of $^{23}\mathrm{Na}$ in AGB stars is minimally influenced by the factor of 4 increase in the present rate compared to the STARLIB-2013 compilation. The present rate does however impact upon the production of nuclei in the Ne-Al region for classical novae, with dramatically improved uncertainties in the predicted isotopic abundances present in the novae ejecta.

The Electromagnetic Mass Analyser (EMMA) is a new vacuum-mode recoil mass spectrometer currently undergoing the final stages of commissioning at the ISAC-II facility of TRIUMF. EMMA employs a symmetric configuration of electrostatic and magnetic deflectors to separate the products of nuclear reactions from the beam, focus them in both energy and angle, and disperse them in a focal plane according to their mass/charge (m/q) ratios. The spectrometer was designed to accommodate the gamma-ray detector array TIGRESS around the target position in order to provide spectroscopic information from electromagnetic transitions. EMMA is intended to be used in the measurement of fusion evaporation, radiative capture, and transfer reactions for the study of nuclear structure and astrophysics. Its complement of focal plane detectors facilitates the identification of recoiling nuclei and subsequent recoil decay spectroscopy. Here we describe the facility and report on commissioning efforts., Comment: 5 figures

We have performed a direct measurement of the ^{19}Ne(p,γ)^{20}Na reaction in inverse kinematics using a beam of radioactive ^{19}Ne. The key astrophysical resonance in the ^{19}Ne+p system has been definitely measured for the first time at E_{c.m.}=456_{-2}^{+5} keV with an associated strength of 17_{-5}^{+7} meV. The present results are in agreement with resonance strength upper limits set by previous direct measurements, as well as resonance energies inferred from precision (^{3}He, t) charge exchange reactions. However, both the energy and strength of the 456 keV resonance disagree with a recent indirect study of the ^{19}Ne(d, n)^{20}Na reaction. In particular, the new ^{19}Ne(p,γ)^{20}Na reaction rate is found to be factors of ∼8 and ∼5 lower than the most recent evaluation over the temperature range of oxygen-neon novae and astrophysical x-ray bursts, respectively. Nevertheless, we find that the ^{19}Ne(p,γ)^{20}Na reaction is likely to proceed fast enough to significantly reduce the flux of ^{19}F in nova ejecta and does not create a bottleneck in the breakout from the hot CNO cycles into the rp process.

The Doppler Shift Lifetimes chamber is an experimental facility designed to measure the mean lifetimes of excited nuclear states that decay within femtoseconds via the detection of their Doppler-shifted γ ray transitions.

EMMA is a recoil mass spectrometer for ISAC-II at TRIUMF that will be used to separate the recoils of nuclear reactions from the beam and to disperse them according to their mass-to-charge ratios. EMMA has been designed for both efficiency and selectivity, possessing large acceptances in angle, mass, and energy without sacrificing the necessary beam suppression and mass resolving power.

Over the past 14 years of conflict, the Department of Defense medical community has made significant strides in patient care. As the conflicts developed, many sources identified a critical gap in en route care, specifically the need for critical care trained personnel for point of injury and intrahospital transfers, as well as improved outcomes for patients who received care from critical care trained providers. As stopgap measures were implemented, the US Army instituted the Critical Care Flight Paramedic Program in order to meet this need of life saving critical care transport. Execution of both an institutional training model as well as a home station training option allows for increased numbers of personnel trained, as well as flexibility for National Guard and Army Reserve units to keep personnel in their area. The Critical Care Flight Paramedic Program's educational outcomes have been exceptional, with National Registry Paramedic pass rates well above the national average. As the program develops, recertification and sustainment of knowledge and skills will be challenges, and novel approaches and flexibility will become critical for continued success.

This Letter reports a study of the highly debated ^{10}Li structure through the d(^{9}Li,p)^{10}Li one-neutron transfer reaction at 100 MeV. The ^{10}Li energy spectrum is measured up to 4.6 MeV and angular distributions corresponding to different excitation energy regions are reported for the first time. The comparison between data and theoretical predictions, including pairing correlation effects, shows the existence of a p_{1/2} resonance at 0.45±0.03 MeV excitation energy, while no evidence for a significant s-wave contribution close to the threshold energy is observed. Moreover, two high-lying structures are populated at 1.5 and 2.9 MeV. The corresponding angular distributions suggest a significant s_{1/2} partial-wave contribution for the 1.5 MeV structure and a mixing of configurations at higher energy, with the d_{5/2} partial-wave contributing the most to the cross section.

R. Reifarth et al: ; 12 págs.; 9 figs.; Open Access funded by Creative Commons Atribution Licence 3.0 ; Nuclear Physics in Astrophysics VI (NPA6), The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process ow and r-process -decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will oer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes., This project was supported by the HGF Young Investigators Project VH-NG-327, EMMI, H4F, HGS-HIRe, JINA, NAVI, DFG and ATHENA.

We have performed the first direct measurement of the ^{38}K(p,γ)^{39}Ca reaction using a beam of radioactive ^{38}K. A proposed ℓ=0 resonance in the ^{38}K+p system has been identified at 679(2) keV with an associated strength of 120_{-30}^{+50} meV. Upper limits of 1.16 (3.5) and 8.6 (26) meV at the 68% (95%) confidence level were also established for two further expected ℓ=0 resonances at 386 and 515 keV, respectively. The present results have reduced uncertainties in the ^{38}K(p,γ)^{39}Ca reaction rate at temperatures of 0.4 GK by more than 2 orders of magnitude and indicate that Ar and Ca may be ejected in observable quantities by oxygen-neon novae. However, based on the newly evaluated rate, the ^{38}K(p,γ)^{39}Ca path is unlikely to be responsible for the production of Ar and Ca in significantly enhanced quantities relative to solar abundances.

26Al is an important radioisotope in astrophysics that provides evidence of ongoing nucleosynthesis in the Galaxy. The 23Na(α, p)26Mg reaction has been identified by a sensitivity study as being one of the most important reactions for the production of 26Al in the convective C/Ne burning shell of massive stars. Owing to large uncertainties in previous experimental data, model calculations are used for the reaction rate of 23Na(α, p)26Mg in this sensitivity study. Current experimental data suggest a reaction rate a factor of ∼40 higher than model calculations. However, a new measurement of this reaction cross section has been made in inverse kinematics in the energy range E(c.m.)=1.28-3.15 MeV at TRIUMF, and found to be in reasonable agreement with the model calculation. A new reaction rate is calculated and tight constraints on the uncertainty in the production of 26Al, due to this reaction, are determined.

The direct particle decay of the isoscalar giant dipole resonance (ISGDR) has been studied in Pb-208 using the (alpha,alpha'p) and (alpha,alpha'n) reactions at a bombarding energy of 200 MeV. The direct-decay channels of proton and neutron emissions were observed in coincidence with the scattered a-particles in order to study the population of proton-hole states in Tl-207 and neutron-hole states in Pb-207. The results of the partial and total branching ratios allowed us to test recently performed continuum-RPA (CRPA) calculations for the ISGDR and thereby to learn about its microscopic structure.

In Wolf-Rayet and asymptotic giant branch (AGB) stars, the (26g)Al(p,γ)(27)Si reaction is expected to govern the destruction of the cosmic γ-ray emitting nucleus (26)Al. The rate of this reaction, however, is highly uncertain due to the unknown properties of key resonances in the temperature regime of hydrogen burning. We present a high-resolution inverse kinematic study of the (26g)Al(d,p)(27)Al reaction as a method for constraining the strengths of key astrophysical resonances in the (26g)Al(p,γ)(27)Si reaction. In particular, the results indicate that the resonance at E(r)=127 keV in (27)Si determines the entire (26g)Al(p,γ)(27)Si reaction rate over almost the complete temperature range of Wolf-Rayet stars and AGB stars.

A kinematically complete measurement was made of the Coulomb dissociation of 813 nuclei on a Pb target at 83 MeV/nucleon. The cross-section was measured at low relative energies in order to infer the astrophysical S-factor for the Be-7(p,gamma)B-8 reaction. A first-order perturbation theory analysis of the reaction dynamics including E1, E2, and M1 transitions was employed to extract the El strength relevant to neutrino-producing reactions in the solar interior. By fitting the measured cross-section from E-rel = 130 keV to 400 keV, we find S-17(0) = 17.8(-1.2)(+1.4) eV b. Semiclassical 1st-order perturbation theory and fully quantum-mechanical continuum-discretized coupled- channels analyses yield nearly identical results for the E1 strength relevant to solar-neutrino flux calculations, suggesting that theoretical reaction mechanism uncertainties need not limit the precision of Coulomb-breakup determinations of the Be-7(p,gamma)B-8 S-factor. A recommended value of S-17(0) based on a weighted average of this and other measurements is presented. This recommendation implies a revised value for the theoretical flux of 8B solar neutrinos, which is also given.

We present preliminary results of a kinematically complete measurement of the Coulomb dissociation of 83 MeV/u 8B on a Pb target. A dipole magnet separated the unreacted beam from the breakup fragments. We measured the Coulomb dissociation cross section at low relative energies in order to extract the astrophysical S factor for the 7Be(p, γ )8B reaction.

The measurement of cosmogenic 81Kr (t1/2=(2.29±0.11)×105 yr) has been proposed for many years as a reliable tool for groundwater dating in the range from 105 to 106 yr. In this paper, we report on the first use of 81Kr to determine the age of groundwater from four wells in the Great Artesian Basin in Australia. As the concentration of 81Kr in old groundwater is only a few hundred atoms per liter, krypton was extracted from large (16 000 l) groundwater samples and was analyzed for the isotopic abundance of 81Kr by accelerator mass spectrometry (AMS) with a cyclotron. 81Kr/Kr isotope ratios of (1.54±0.22)×10−13, (1.78±0.26)×10−13, (2.19±0.28)×10−13 and (2.63±0.32)×10−13, respectively, were measured for these samples. It is reasonable to assume that krypton dissolved in surface water in contact with the atmosphere has the known atmospheric 81Kr/Kr ratio of (5.20±0.40)×10−13. The observed reduction of isotope ratios in the groundwater samples can then be interpreted as being due to radioactive decay since recharge. This results in respective groundwater ages of: (4.02±0.51)×105 yr, (3.54±0.50)×105 yr, (2.87±0.38)×105 yr and (2.25±0.42)×105 yr. The main emphasis of this paper lies on the description of the analytic procedure to extract a reliable 81Kr signal from large groundwater samples. Although the uncertainties are still relatively large (primarily due to counting statistics caused by the low cyclotron AMS efficiency), the new technique enabled for the first time a definite determination of residence times for old groundwater with 81Kr. It thus confirms the hope that this radionuclide may become a very valuable tool for groundwater dating.

The structure of the halo nucleus ${}^{11}\mathrm{Be}$ has been studied using the reaction ${}^{9}\mathrm{Be}{(}^{11}\mathrm{Be}{,}^{10}\mathrm{Be}+\ensuremath{\gamma})X$ at 60 MeV/nucleon. The ground state structure of ${}^{11}\mathrm{Be}$ is determined by comparing the experimental cross sections to a calculation combining spectroscopic factors from the shell model with $l$-dependent single-particle cross sections obtained in an eikonal model. This experiment shows the dominant $1s$ single-particle character of the ${}^{11}\mathrm{Be}$ ground state and indicates a small contribution of $0d$ admixture in the wave function. After correction for the approximately $22%$ intensity to excited levels, a clean and precise distribution of parallel momentum for knockout from the $1s$ halo wave function is obtained for the first time.

Measurements of deexcitation $\ensuremath{\gamma}$ rays in coincidence with the momentum distribution of the projectile residues produced in reactions of the type ${}^{9}\mathrm{Be}{(}^{28}\mathrm{P}{,}^{27}\mathrm{Si}+\ensuremath{\gamma})X$ at energies around 65 MeV/u are used to study single-nucleon stripping to individual states. The cross sections are compared with calculations based on an eikonal model description of the reaction and the shell model. The measurements indicate that the halo character of the ground state and other detailed spectroscopic information can be derived using knockout reactions in inverse kinematics.

In an effort to understand the implications of Coulomb dissociation experiments for the determination of the 7Be(p,γ) 8B reaction rate, longitudinal momentum distributions of 7Be fragments produced in the Coulomb dissociation of 44 and 81 MeV/u8B beams on a Pb target were measured. These distributions are characterized by asymmetries interpreted as the result of interference between E1 and E2 transition amplitudes in the Coulomb breakup. At the lower beam energy, both the asymmetries and the measured cross sections are well reproduced by first order perturbation theory calculations, allowing a determination of the E2 strength. The measurement yields SE2/SE1=6.7−1.9+2.8×10−4 at the 0.63 MeV 1+ resonance. If higher order dynamical effects are not negligible, then the E2 strength extracted here is a lower limit.

Total reaction cross sections, σ R , on Si were measured near 40 A MeV for the proton-halo candidate 12 N and the two-proton-halo candidate 17 Ne, and were compared with σ R for other light proton-rich nuclei. The A -dependence shows enhanced σ R 's for 12 N and 17 Ne, relative to their neighbors, but the effect is smaller than for 8 B which has been argued to have a proton halo. In general, nuclei with loosely bound last protons ( S p ⩽ 1.5 MeV) have significantly larger σ R 's than their neighbors. Cross sections for charge-removal from 12 N and 17 Ne also were obtained.