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The 24Mg(p,α)21 Na transfer reaction has been previously studied for a spectroscopic study of 21Na [Cha et al., Phys. Rev. C 96, 025810 (2017)]. In this follow-up analysis, the proton decays of the excited states of the radionuclide 21Na, which were measured simultaneously, are reported. By investigating the coincidence between the reaction α-particles and decay protons, we were able to identify three groups of events that are associated with the energy levels in 20Ne. The 20Ne excitation energy plot was obtained as a result. The four lowest known energy levels in 20Ne (the ground state and excited states at Ex = 1.633, 4.247 and 4.966 MeV) were clearly observed.

We report the first (in)elastic scattering measurement of ^{25}Al+p with the capability to select and measure in a broad energy range the proton resonances in ^{26}Si contributing to the ^{22}Mg(α,p) reaction at type I x-ray burst energies. We measured spin-parities of four resonances above the α threshold of ^{26}Si that are found to strongly impact the ^{22}Mg(α,p) rate. The new rate advances a state-of-the-art model to remarkably reproduce light curves of the GS 1826-24 clocked burster with mean deviation

A fast ionization chamber with a high counting rate was commissioned at the 8 MV tandem accelerator complex of Kyushu University in Japan. Heavy ion beams consisting of 12C and 16O with Ebeam = 36 MeV were used to investigate the detector performance. By using various beam intensities ranging from 103 to 106 particles per second (pps), the maximum counting rate of the ion counter was measured to be about 8 × 105 pps. The detector performance under different gases was also investigated using two common gases in the ionization chamber: isobutane and P-10 gases. The results show that the negative effects due to pileups, which are often observed at high counting rates, can be greatly reduced when P-10 gas is used.

Decay protons from excited states in $^{21}\mathrm{Na}$ populated through a previously reported $^{24}\mathrm{Mg}(p,\ensuremath{\alpha})^{21}\mathrm{Na}$ transfer reaction [Cha et al., Phys. Rev. C 96, 025810 (2017)] were analyzed to extract the proton branching ratios of the energy levels. By utilizing 31-MeV proton beams from the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory and isotopically enriched $^{24}\mathrm{Mg}$ solid targets, the decay protons were detected in coincidence with $\ensuremath{\alpha}$ particles from the $(p,\ensuremath{\alpha})$ reaction using a silicon strip detector array. Proton decay branching ratios of several $^{21}\mathrm{Na}$ levels were deduced for the $p0$ and $p1$ decay channels to the ground and first excited states in $^{20}\mathrm{Ne}$, respectively.

The cosmological lithium problem (CLP) stems from the outstanding discrepancy between theoretical predictions and astronomical observations of primordial lithium abundances. For the radiogenic production of 7Li, 7Be plays a pivotal role in the Big Bang nucleosynthesis (BBN). Nevertheless, the data for neutron-induced 7Be destruction processes were still sparse, and especially lacked information on the contributions of transitions to the 7Li excited states. In this work, we have determined the 7BeLi, 7BeLi*, and 7BeHe reaction cross sections by means of the Trojan Horse method. The present and the previous data were analyzed together by a multichannel R-matrix fit, providing an improved uncertainty evaluation of the channel and the first-ever quantification of the contribution in the BBN-relevant energy range. We implemented the revised total reaction rate summing both the and contributions in a state-of-the-art BBN code PRIMAT. As a consequence, the present nuclear-physics data offers a reduction of the predicted 7Li abundance by about one-tenth, which would impose a stricter constraint on BBN and head us in the correct direction to the CLP solution.

The mechanism of reactions with weakly-bound proton-rich nuclei at energies near the Coulomb barrier is a long-standing open question owing to the paucity of experimental data. In this study, a complete kinematics measurement was performed for the proton drip-line nucleus 17F interacting with 58Ni at four energies near the Coulomb barrier. Thanks to the powerful performance of the detector array, exhaustive information on the reaction channels, such as the differential cross sections for quasielastic scattering, exclusive and inclusive breakup, as well as for fusion-evaporation protons and alphas, was derived for the first time. The angular distributions of quasielastic scattering and exclusive breakup can be described reasonably well by the continuum-discretized coupled-channels calculations. The inclusive breakup was investigated using the three-body model proposed by Ichimura, Austern, and Vincent, and results indicate the non-elastic breakup is the dominant component. The total fusion cross sections were determined by the fusion-evaporation protons and alphas. Based on the measured exclusive breakup data, the analysis of the classical dynamical simulation code PLATYPUS demonstrates that the incomplete fusion plays a minor role. Moreover, compared with 16O+58Ni, both the reaction and total fusion cross sections of 17F+58Ni exhibit an enhancement in the sub-barrier energy region, which mainly arises from couplings to the continuum states. This work indicates that the information of full reaction channels is crucially important to comprehensively understand the reaction mechanisms of weakly bound nuclear systems.

Nuclear reactions play a key role in the framework of the Big Bang Nucleosynthesis. A network of 12 principal reactions has been identified as the main path that drove the elemental nucleosynthesis in the first 20 min of the history of the Universe. Among them an important role is played by neutron-induced reactions, which, from an experimental point of view, are usually a difficult task to be measured directly. Nevertheless big efforts in the last decades have led to a better understanding of their role in the primordial nucleosynthesis network. In this work we apply the Trojan Horse Method to extract the cross section at astrophysical energies for the $$^3\text {He}$$ (n,p) $$^3\text {H}$$ reaction after a detailed study of the $$^2\hbox {H}$$ ( $$^3\text {He}$$ ,pt)H three-body process. Data extracted from the present measurement are compared with other published sets.

We report the first (in)elastic scattering measurement of ^{25}Al+p with the capability to select and measure in a broad energy range the proton resonances in ^{26}Si contributing to the ^{22}Mg(α,p) reaction at type I x-ray burst energies. We measured spin-parities of four resonances above the α threshold of ^{26}Si that are found to strongly impact the ^{22}Mg(α,p) rate. The new rate advances a state-of-the-art model to remarkably reproduce light curves of the GS 1826-24 clocked burster with mean deviation9% and permits us to discover a strong correlation between the He abundance in the accreting envelope of the photospheric radius expansion burster and the dominance of ^{22}Mg(α,p) branch.

The α-clusterization of an atomic nucleus has been studied for a long time, even from the earliest days of nuclear physics. Our understanding of the α-cluster structure is, however, mainly limited to the self-conjugate A = 4n (n = 2, 3, 4, · · · ) light nuclei and some of the neutron-rich radionuclides such as 10Be, 11B, and 14C. In order to study the α-cluster structure of a neutron-deficient 22Mg nucleus, we have measured the 18Ne(α, α)18Ne scattering in inverse kinematics by using radioactive 18Ne beams and the 4He gas target at the Center for Nuclear Study radioactive ion beam separator of the University of Tokyo. Recoiling α particles from the scattering were detected by using silicon strip detectors, which constitute ΔE-E telescopes for particle identification. By adopting a thick target method, we were able to investigate a wide range of excitation energies Ex = 9.9 - 16.5 MeV in 22Mg in this work.

The intense γ-rays from classical novae are emitted due to the β-decay of 18F which is produced by the Hot-CNO cycle. The reaction rate of 18F(p,α)15O affects the prediction of the abundance of 18F. The main contribution to this reaction rate is from the resonances in 19Ne near and above the proton threshold. Hence, many experiments and theoretical works have been performed on the low-lying 18F+p resonances. One of the methods for investigating 19Ne parameters is studying the mirror nucleus 19F. α elastic scattering experiment was performed with a 7 MeV/u 15N beam for investigating the resonance parameters in 19F using the thick target method in inverse kinematics at the radioactive beam facility CRIB of the Center for Nuclear Study, the University of Tokyo. The excitation function of 19F was obtained for the excitation energy Ex = 6.7 - 7.7 MeV, and the parameters of the resonance states in 19F were determined using an R-matrix analysis.

We conducted a measurement of 18Ne + α scattering in inverse kinematics , in order to search for experimental evidence of α -cluster structure in 22Mg above the alpha threshold ( E thr = 8 . 14 MeV ) and determine the astrophysical rates of the 18Ne( α , p)21Na reaction under the conditions of break-out from the Hot-CNO cycle. A high intensity 18 Ne beam at 2.54 AMeV was successfully produced at CRIB (CNS Radioactive Ion Beam separator) of the Center for Nuclear Study, the University of Tokyo. This paper presents the in-flight production of the radioactive 18Ne beam by using the production reaction 3He(16O, 18Ne)n with a windowed cryogenic gas target, which was employed in the mentioned resonant α -scattering experiment.

It is a well-known fact that a cluster of nucleons can be formed in the interior of an atomic nucleus, and such clusters may occupy molecular-like orbitals, showing characteristics similar to normal molecules consisting of atoms. Chemical molecules having a linear alignment are commonly seen in nature, such as carbon dioxide. A similar linear alignment of the nuclear clusters, referred to as linear-chain cluster state (LCCS), has been studied since the 1950s, however, up to now there is no clear experimental evidence demonstrating the existence of such a state. Recently, it was proposed that an excess of neutrons may offer just such a stabilizing mechanism, revitalizing interest in the nuclear LCCS, specifically with predictions for their emergence in neutron-rich carbon isotopes. Here we present the experimental observation of {\alpha}-cluster states in the radioactive 14C nucleus. Using the 10Be+{\alpha} resonant scattering method with a radioactive beam, we observed a series of levels which completely agree with theoretically predicted levels having an explicit linear-chain cluster configuration. We regard this as the first strong indication of the linear-chain clustered nucleus., Comment: 15 pages, 3 figures

Studies on nuclear astrophysics, nuclear structure, and other interests have been performed using the radioactive-isotope (RI) beams at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study (CNS), the University of Tokyo. The elastic resonant scattering is a striking tool to study astrophysical reactions and nuclear clusters. In particular, when it is coupled with a thick target and inverse kinematics, the measurement can be very efficient and even feasible with RI beams. By measuring resonant scattering, we can study the properties of resonant states which could play an important role in the astrophysical reaction, or have an exotic nuclear structure. The 10Be+α elastic scattering has been measured at CRIB, and three resonances which are in agreement with the prediction of a linear-chain structure by Suhara-En’yo were observed, giving a strong indication of the existence of such an exotic structure. Measurements based on the indirect technique of the reaction measurement, such as the Trojan horse method, have also been performed at CRIB.

The $^{15}$O($\alpha$,$\gamma$)$^{19}$Ne reaction is responsible for breakout from the hot CNO cycle in Type I x-ray bursts. Understanding the properties of resonances between $E_x = 4$ and 5 MeV in $^{19}$Ne is crucial in the calculation of this reaction rate. The spins and parities of these states are well known, with the exception of the 4.14- and 4.20-MeV states, which have adopted spin-parities of 9/2$^-$ and 7/2$^-$, respectively. Gamma-ray transitions from these states were studied using triton-$\gamma$-$\gamma$ coincidences from the $^{19}$F($^{3}$He,$t\gamma$)$^{19}$Ne reaction measured with GODDESS (Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies) at Argonne National Laboratory. The observed transitions from the 4.14- and 4.20-MeV states provide strong evidence that the $J^\pi$ values are actually 7/2$^-$ and 9/2$^-$, respectively. These assignments are consistent with the values in the $^{19}$F mirror nucleus and in contrast to previously accepted assignments.

This work presents the nuclear level scheme (NLS) of 164Dy nucleus obtained from the 163Dy(n t h ,2γ) experiment. The latter has used a γ − γ coincidence spectrometer to measure the two-step gamma cascades corresponding to the decays from the compound state to 9 low-lying states of 164Dy, whose energies are 0.0, 73.393, 242.234, 761.815, 828.215, 915.991, 976.916, 1039.309, and 1122.774 keV. Based on the measured data, the 164Dy NLS, which consists of 64 primary gamma transitions and their corresponding intermediate levels, together with 132 secondary gamma transitions, has been constructed. Among these data, 20 primary gamma transitions, 51 intermediate levels, and 63 secondary gamma transitions are found to be the same as those currently exist in the Evaluated Nuclear Structure Data File (ENSDF) database. The remaining data, which include 44 primary transitions, 13 intermediate levels, and 69 secondary transitions, are therefore, considered as an update for the NLS of 164Dy. In particular, the spin values of 57 observed intermediate levels have been tentatively assigned by means of transition rules. Furthermore, the influence of the present experimental data on the nuclear level density and radiative strength function is also discussed.

GODDESS is a coupling of the charged-particle detection system ORRUBA to the gamma-ray detector array Gammasphere. This coupling has been developed in order to facilitate the high-resolution measurement of direct reactions in normal and inverse kinematics with stable and radioactive beams. GODDESS has been commissioned using a beam of 134 Xe at 10 MeV/A, in a campaign of stable beam measurements. The measurement demonstrates the capabilities of GODDESS under radioactive beam conditions, and provides the first data on the single-neutron states in 135 Xe, including previously unobserved states based on the orbitals above the N=82 shell closure.

A position-sensitive ionization chamber has been constructed and commissioned at the Physics Department of Sungkyunkwan University to extract position information on incident charged particles for future nuclear reaction measurements. By utilizing the newly-designed position-sensitive anodes and the previously-commissioned portable gas-filled ionization chamber by Chae et al., position information on incident particles could be obtained. The device was tested with an 241Am α-emitting source, and the standard deviation of the fitted Gaussian distribution was measured to be 1.76 mm when a collimator with a 2 mm hole was used.

We performed indirect measurements of the neutron-induced reactions \(^{7}\)Be(n,p)\(^{7}\)Li and \(^{7}\)Be(n,\(\mathsf \alpha \))\(^{4}\)He simultaneously by the Trojan Horse method relevant to the cosmological \(^7\)Li problem. Preliminary excitation functions for \((n,p_0)\) and \((n,\alpha )\) are basically consistent with the previous studies, and new information about the \((n,p_1)\) contribution suggests possible enhancement of the total reaction rate.

A direct test of nova explosion models comes from the observation of γ rays created in the decay of radioactive isotopes produced in the nova. One such isotope, 18F, is believed to be the main source of observable γ rays at and below 511 keV. The main destruction mechanism of 18F is thought to be the 18F(p,α)15O reaction, and uncertainties in the reaction rate arise from uncertainties in the energies, spins, and parities of the nuclear levels in 19Ne above the 18F+p threshold. To measure the properties of these levels, the 19F(3He,t)19Ne∗(γ) reaction was studied at Argonne National Laboratory and the Nuclear Science Laboratory at the University of Notre Dame.A direct test of nova explosion models comes from the observation of γ rays created in the decay of radioactive isotopes produced in the nova. One such isotope, 18F, is believed to be the main source of observable γ rays at and below 511 keV. The main destruction mechanism of 18F is thought to be the 18F(p,α)15O reaction, and uncertainties in the reaction rate arise from uncertainties in the energies, spins, and parities of the nuclear levels in 19Ne above the 18F+p threshold. To measure the properties of these levels, the 19F(3He,t)19Ne∗(γ) reaction was studied at Argonne National Laboratory and the Nuclear Science Laboratory at the University of Notre Dame.

We report on the development of a new, portable detector array for charged particles with a low detection threshold to study the reaction mechanisms of exotic nuclear systems at energies around the Coulomb barrier. In order to identify both light and heavy particles simultaneously, the array consists of ten units of $ \Delta E$-$ E_{\mathrm{R}}$ telescopes, where each one is made up of four detection layers: one ionization chamber, one 40 (or 60)μm double-sided silicon strip detector and two quadrant silicon detectors with thicknesses of 300μm and 1000 (or 1500)μm, respectively. The frame of the ionization chamber is innovatively designed with printed circuit boards, thus the mass of each telescopic unit was reduced significantly which eases transport and installation requirements to different radioactive ion beam lines around the globe. The commissioning experiments focused on elucidating several reaction mechanisms encountered in the 17F + 58Ni and 17F + 208Pb systems, and we demonstrated that the array has a sufficient capability to enable charged particle identification over a large range of Z. Light particles like p, d, $ \alpha$ as well as heavy ions like 16O and 17F can be clearly distinguished. Considering these properties, this newly developed array enables in-depth investigation of the novel reaction mechanisms which are manifested in the collisions of exotic nuclei with differing isotopes.

Detection of nuclear-decay γ rays provides a sensitive thermometer of nova nucleosynthesis. The most intense γ-ray flux is thought to be annihilation radiation from the β^{+} decay of ^{18}F, which is destroyed prior to decay by the ^{18}F(p,α)^{15}O reaction. Estimates of ^{18}F production had been uncertain, however, because key near-threshold levels in the compound nucleus, ^{19}Ne, had yet to be identified. We report the first measurement of the ^{19}F(^{3}He,tγ)^{19}Ne reaction, in which the placement of two long-sought 3/2^{+} levels is suggested via triton-γ-γ coincidences. The precise determination of their resonance energies reduces the upper limit of the rate by a factor of 1.5-17 at nova temperatures and reduces the average uncertainty on the nova detection probability by a factor of 2.1.

Software for genuinely event-by-event analysis and event reconstruction of data obtained by using an active target has been developed in the graphical user interface under the CERN ROOT framework. The primary motivation for developing the software was to provide physicists who perform experiments using an active target a more user-friendly environment for the purpose of investigating the performance of detection systems and obtaining ideas about physics from a large amount of experimental data. To test the performance of the software, we analyzed experimental data from a 16N radioactive ion beam experiment for α-decay measurements. As a result of the analysis, we observed the Bragg curve and measured the range of the 16N RI beam in the detector. Data were calibrated against the calculation after comparing the Bragg curve to the one obtained from an energy loss calculation in P-10 gas. We present a detailed description of the analysis software and its test results.

We performed an experiment to measure proton resonant elastic scattering of a mixed 26m,gAl beam with a thick target in inverse kinematics by using CNS RI beam sep-arator, located at RIKEN Nishina Center. It aimed to search for strong proton resonances and determine level properties of low spin-parity states in 27Si. Diagnosis of the 26mAl purity of the beam by annihilation radiation are discussed.

Astrophysical observables that are directly linked to nuclear physics inputs provide critical and stringent constraints on nucleosynthetic models. As 26Al was the first specific radioactivity observed in the Galaxy, its origin has fascinated the nuclear astrophysics community for nearly forty years. Despite extensive research, the precise origins of 26Al remain elusive. At present, the sum of all putative stellar contributions generally overestimates the 26Al mass in the interstellar medium. Among the many reactions that influence the yield of 26Al, radiative proton capture on its isomer 26mAl is one of the least constrained reactions by experimental data. To this end, we developed a 26Al isomeric beam and performed proton elastic scattering to search for low-spin states in 27Si. The experimental method and the preliminary results of this on-going study will be presented.

International audience; Studies on nuclear astrophysics, nuclear structure, and other interests have been performed using the radioactive-isotope (RI) beams at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study (CNS), the University of Tokyo. A type of measurement to study astophysical reactions at CRIB is by the elastic resonant scattering with the thick-target method in inverse kinematics. An example is the α resonant scattering with 7Be beam, related to the astrophysical 7Be(α,γ) reactions, which is relevant in the hot p-p chain and νp-process in supernovae. Other α resonant scattering measurements with 30S, 10Be, 15O, and 18Ne beams have been performed at CRIB, using the thick-target method. There have also been measurements based on other experimental methods. The first Trojan horse method (THM) measurement using an RI beam has been performed at CRIB, to study the 18F(p, α)15O reaction at astrophysical energies via the three body reaction 2H(18F, α15O)n. The 18F(p, α)15O reaction rate is crucial to understand the 511-keV γ-ray production in nova explosion phenomena, and we successfully evaluated the reaction cross section at novae temperature and below experimentally for the first time.

The cosmological 7Li problem has been one of the big issues left in the standard Big-Bang nucleosynthesis (BBN) model. In order to determine the radiogenic 7Li abundance by the BBN, it is important to know the production and the destruction rate of 7Be rather than 7Li itself. We performed indirect measurements of the relevant neutron-induced reactions 7Be(n, p)7Li and 7Be(n, α)4He simultaneously by the Trojan Horse Method (THM) via the three-body reactions 7Be(d,7Lip)1H and 7Be(d, αα)1H. A 7Be radioactive-isotope (RI) beam at 3.16 MeV/u was produced at Center-for-Nuclear-Study RI Beam (CRIB) separator. The Q-value spectra shows the evidence of the three-body channels of interest. We confirmed that the THM was applicable to the present measurements by the momentum distributions of the spectator proton. Preliminary excitation functions are roughly consistent with the previous studies, moreover providing new data in the BBN energy range, and suggesting that new information about the 7Be(n, p1)7Li* contribution may be obtained by carrying out a further data analysis.

The $^{24}\mathrm{Mg}(p,\ensuremath{\alpha})^{21}\mathrm{Na}$ reaction was measured at the Holifield Radioactive Ion Beam Facility of the Oak Ridge National Laboratory to study the spectroscopy of the radionuclide $^{21}\mathrm{Na}$. A 31-MeV proton beam from the 25 MV tandem accelerator bombarded isotopically enriched $^{24}\mathrm{Mg}$ targets. Recoiling $^{4}\mathrm{He}$ particles were identified by an annular silicon strip detector array. Two energy levels at ${E}_{x}=6.594$ and 7.132 MeV were observed for the first time. By comparing the experimentally obtained angular distributions and distorted wave Born approximation calculations, the spins and parities of $^{21}\mathrm{Na}$ energy levels were constrained. The astrophysically-important $^{17}\mathrm{F}(\ensuremath{\alpha},p)^{20}\mathrm{Ne}$ reaction rate was also calculated for the first time using resonance parameters for 12 energy levels.

A new portable gas-filled ionization chamber has been designed and constructed at the Physics Department of Sung Kyun Kwan University. To overcome the maximum count rate of ∼105 particles per second of a conventional ionization chamber, which utilizes a Frisch grid, and to enhance the portability of a detector, we adopted the design of multiple electrodes and modified it from the original designs by Kimura et al. and Chae et al. The new design utilizes a stack of multiple electrodes installed perpendicular to the optical beam axis. This configuration provides a fast response time for the detector, which is essential for high-rate counting. The device has been tested with a 241Am (t1/2 = 432.2 years) radioactive α source, which mainly emits 5.486-MeV (branching ratio of 85%) and 5.443-MeV (branching ratio of 13%) α particles. An energy resolution of 6.3% was achieved.

The advent of radioactive ground-state beams some three decades ago ultimately sparked a revolution in our understanding of nuclear physics. However, studies with radioactive isomer beams are sparse and have often required sophisticated apparatuses coupled with the technologies of ground-state beams due to typical mass differences on the order of hundreds of keV and vastly different lifetimes for isomers. We present an application of a isomeric beam of 26m Al to one of the most famous observables in nuclear astrophysics: galactic 26 Al. The characteristic decay of 26 Al in the Galaxy was the first such specific radioactivity to be observed originating from outside the Earth some four decades ago. We present a newly-developed, novel technique to probe the structure of low-spin states in 27 Si. Using the Center for Nuclear Study low-energy radioisotope beam separator (CRIB), we report on the measurement of 26m Al proton resonant elastic scattering conducted with a thick target in inverse kinematics. The preliminary results of this on-going study are presented.

We study the variability of the nova-like cataclysmic variable TT Ari, on time-scales of between minutes and months. The observations in the filter R were obtained at the 40-cm telescope of the Chungbuk National University (Korea). TT Ari was in the "negative superhump" state after its return from the "positive superhump" state, which lasted 8 years. The ephemeris for 12 best pronounced minima is $T_{min}=BJD 2453747.0700(47)+0.132322(53)E.$ where numbers in digits are errors in units of the last digit. The phases of minima may reach 0.2, indicating non-eclipse nature of these minima. The quasi-periodic oscillations (QPO) are present with a mean "period" of 21.6 min and mean semi-amplitude of 36 mmag. This value is consistent with the range 15-25 minutes reported for previous "negative superhump" states and does not support the hypothesis of secular decrease of the QPO period. Either the period, or the semi-amplitude show significant night-to-night variations. According to the position at the two-parameter diagrams, the interval of observations was splitted into 5 parts, showing different characteristics which are discussed in this paper. The system is an excellent laboratory to study processes resulting in variations at time-scales from seconds to decades and needs further monitoring at various states of activity., Comment: 14pages,10figures, accepted in Astronomy and Astrophysics

The $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain spins and parities of energy levels in $^{21}$Na for the astrophysically important $^{17}$F($\alpha, p$)$^{20}$Ne reaction rate calculation. 31 MeV proton beams from the 25-MV tandem accelerator and enriched $^{24}$Mg solid targets were used. Recoiling $^{4}$He particles from the $^{24}$Mg($p$, $\alpha$)$^{21}$Na reaction were detected by a highly segmented silicon detector array which measured the yields of $^{4}$He particles over a range of angles simultaneously. A new level at 6661 $\pm$ 5 keV was observed in the present work. The extracted angular distributions for the first four levels of $^{21}$Na and Distorted Wave Born Approximation (DWBA) calculations were compared to verify and extract angular momentum transfer., Comment: 11 pages, 6 figures, proceedings of the 18th International Conference on Accelerators and Beam Utilization (ICABU2014)

Alpha resonant scattering is a simple and promising method to study α-cluster structure in nuclei. It has several good features which enable us to perform measurements with short-lived and relatively low-intense RI beams. Several measurements on alpha resonant scattering have been carried out at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. Recent α resonant scattering studies at CRIB, using7Li,7Be and10Be beams with a helium gas target, are discussed.

Studies on nuclear reactions relevant for astrophysics have been performed using the radioactive-isotope (RI) beams at the low-energy RI beam separator CRIB, operated by Center for Nuclear Study (CNS), the University of Tokyo. A type of measurement to study astrophysical reactions at CRIB is by the elastic resonant scattering with the thick-target method in inverse kinematics. We introduce the α resonant scattering with 7 Be beam, related to the astrophysical 7 Be(α, γ) reactions, which is relevant in the hot p-p chain and νp-process in supernovae. Other α resonant scattering measurements with 30 S, 10 Be, 15 O, and 18 Ne beams have been performed at CRIB, using the thick-target method.

Bulgogi (Korean traditional barbecued beef) is the most well-known Korean food to foreigners. There are, however, few studies on its sensory characteristics and consumer acceptability. This study was performed to identify the sensory attributes of Bulgogi samples prepared with different formulation and to compare the consumer acceptability in Korea and the United States. Bulgogi samples were prepared with varying levels of sugar and soy sauce with/without garlic or sesame oil. Descriptive analysis was conducted by 8 trained panelists. In consumer tests, 42 consumers in Seoul, Korea, 53 consumers in Davis (Calif., U.S.A.), and 39 consumers in St. Paul (Minn., U.S.A.) participated. Higher levels of sugar and soy sauce (SSS) significantly increased sweetness, saltiness, MSG taste, and soy sauce odor/flavor compared to the control made with the standard formula (CON). Elimination of sesame oil (ESO) significantly decreased sesame oil odor/flavor and oiliness, but increased green onion flavor. Elimination of garlic (EGC) significantly increased grilled beef odor/flavor, sesame oil odor/flavor, and oiliness, but decreased intensities of all the other attributes except bitterness. The consumers in Korea and the United States rated their overall liking for all samples similarly, preferring SSS to CON, EGC, and ESO. However Korean consumers seemed to detect the differences caused by formulation changes better than the U.S. consumers and these perceived differences seemed to impact the hedonic and the just-about-right ratings. Increase in soy sauce and sugar increased both Korean and the U.S. consumers’ acceptability of Bulgogi, whereas eliminating garlic did not influence the consumer acceptability despite of its significant impact on sensory attributes. Practical Application: The food industry is increasingly interested in ethnic foods that satisfy sophisticated appetite of today's consumers. Korean cuisine is recently gaining popularity and perceived as “adventurous and spicy,” appealing to researchers and marketers in the food industry worldwide. However, it is not easy to develop a new product based on ethnic cuisine because nonsensory factors, such as food neophobia and openness to new culture, can evoke adverse responses from the consumers. A systematic sensory approach can guide the product development by identifying both sensory and nonsensory factors affecting consumer acceptability. This study investigated sensory attributes of Bulgogi (Korean traditional barbecued beef), one of the most famous Korean foods, and compared consumer acceptability between Korea and the United States. The outcomes of this study, such as flavor profiles, consumer responses, evaluation procedure, and approaches taken for cross-cultural comparison, will provide the food industries with valuable information that will help to develop effective strategies for commercializing ethnic foods including recipe development for Bulgogi marinades.

Alpha resonant scattering is a simple and promising method to study α-cluster structure in nuclei. It has several good features which enable us to perform measurements with short-lived and relatively low-intense RI beams. Several measurements on alpha resonant scattering have been carried out at CRIB (CNS Radioactive Ion Beam separator), which is a low-energy RI beam separator at Center for Nuclear Study (CNS) of the University of Tokyo. Recent α resonant scattering studies at CRIB, using 7Li, 7Be and 10Be beams with a helium gas target, are discussed.

Several arabinosyl-, xylosyl-, lyxosyl, 5'-deoxy-, acyclo-, 2,2'-anhydro-, 2,3'-anhydro-2'-deoxy-, 2,5'-anhydro-, 6,5'-cyclo-, and carbocyclic analogues of uridine with various 5-substitutions (fluoro, methyl, bromo, ethyl, benzyl, or benzyloxybenzyl) have been tested and compared with their corresponding ribo- and 2'-deoxyribosides for their potency to inhibit uridine phosphorylase (UrdPase) from both mouse and human livers. The effect of the alpha- and beta-configurations of the glycosidic bond was also tested. Xylo-, lyxo-, 2,3'-anhydro-2'-deoxy-, 6,5'-cyclo-, and carbocyclic uridines did not bind to the enzyme. Ribosides bound better than the corresponding 2'-deoxyribosides, which were better than the 5'-deoxyribosides. 2'-alpha-Deoxyribosides bound to the enzyme, albeit less tightly than the corresponding beta-anomers. The acyclo- and 2,2'-anhydrouridines were all potent inhibitors with the 2,2'-anhydro- derivatives being the most potent. 2,5'-Anhydrouridine bound to UrdPase less effectively than 2,2'-anhydrouridine and acyclouridine. Arabinosyl uracil was at best a very poor inhibitor but binds better if a benzyl group is added at the 5-position of the pyrimidine ring. This binding was enhanced further by adding a 5-benzyloxybenzyl group. A similar enhancement of the binding with increased hydrophobicity at the 5-position of the pyrimidine ring was observed with ribosides, alpha- and beta-anomers of the 2'-deoxyribosides, acyclonucleosides, and 2,2'-anhydronucleosides. The inhibitory potencies of these compounds with UrdPase from human liver roughly parallel those obtained with UrdPase from mouse liver. It is concluded that the presence of a N-glycosidic bond as well as a properly oriented 3'-hydroxyl group are prerequisites for a nucleoside ligand to bind to UrdPase. On the other hand, the presence of a 2'- or 5'-hydroxyl group or an N-glycosidic bond in the beta-configuration enhances but is not essential for binding. Furthermore, the potency of the binding of 2,2'-anhydrouridines (fixed syn-isomers) in contrast to the complete lack of binding of the 6,5'-cyclouridines (fixed anti-isomers) to UrdPase indicates that the binding of ligands to this enzyme is in the syn-conformation around the N-glycosidic bond.