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International audience; Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) experi-ment is designed to study the composition and energy spectra of cosmic-ray particles from 10^12 to 10^15 eV. ISS-CREAM was launched and deployed to the ISS in August 2017. The ISS-CREAM payload employs a Silicon Charge Detector for charge measurements, Top and Bot-tom Counting Detector for electron-hadron separation and a low-energy trigger, a Boronated Scintillator Detector for additional electron-hadron separation, and a Calorimeter (CAL) for en-ergy measurements and a high-energy trigger. The CAL is constructed of 20 layers of tungsten plates interleaved with scintillating fiber ribbons read out by hybrid-photodiodes (HPDs) and densified carbon targets. Each CAL layer is made of 3.5 mm (1 X_0) thick tungsten plates alter-nating with fifty 0.5 mm thick and 1 cm wide scintillating fiber ribbons. Consecutive layers of fiber ribbons are installed orthogonal to each other. Energy deposition in the CAL determines the particle energy and provides tracking information to determine which segment(s) of the charge detectors to use for the charge measurement. Tracking for showers is accomplished by extrapolating each shower axis back to the charge detectors. The performance of the ISS-CREAM CAL during flight is presented.

International audience; Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) is an experiment for studying the origin, acceleration, and propagation mechanisms of high-energy cosmic rays. The ISS-CREAM instrument was launched on the 14th of August 2017 to the ISS aboard the SpaceX-12 Dragon spacecraft. The Top and Bottom Counting Detectors (TCD/BCD) are parts of the ISS-CREAM instrument and designed for studying electron and gamma-ray physics. The TCD/BCD each consist of an array of 20 × 20 photodiodes on a plastic scintillator. The TCD/BCD can separate electrons from protons by using the difference between the shapes of electromagnetic and hadronic showers in the high energy region. The Boosted Decision Tree (BDT) method, which is a deep learning method, is used in this separation study. We will present results of the electron/proton separation study and rejection power in various energy ranges.

International audience; The Cosmic Ray Energetics And Mass (CREAM) instrument on the International Space Station (ISS) is an experiment to study origin, propagation, acceleration and elemental composition of cosmic rays. The Top Counting Detector (TCD) and Bottom Counting Detector (BCD) are parts of the detector suite of the ISS-CREAM experiment and are designed to separate electrons and protons for studying electron and gamma-ray physics. In addition, the TCD/BCD provide a redundant trigger to that of the calorimeter and a low energy trigger to the ISS-CREAM instrument. After launching, the TCD/BCD trigger was found to be working well. Also, the TCD/BCD have been stable and their hit positions were confirmed to be well matched with other detectors on board. We present the performance and status of the TCD/BCD in flight.

International audience; The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is a space-borne mission designed for the precision measurement of the energy and elemental composition of cosmic rays. The Silicon Charge Detector (SCD), placed at the top of the ISS-CREAM payload, consists of 4 layers. Each layer has 2688 silicon pixels and associated electronics arranged in such a fashion that its active detection area of 78.2 × 73.6 cm 2 is free of dead area. The foremost goal of the SCD is to efficiently and precisely measure the charge of cosmic rays passing through it. The 4-layer configuration was chosen to achieve the best precision in measuring the charge of cosmic rays within the constraints on the mass, volume and power allotted to it. The amount of material used for its support structure was minimized as well to reduce the chance of interactions of the cosmic ray within the structure. Given the placement of the SCD, its 4-layer configuration and the minimal amount of material in the cosmic-ray trajectory, the SCD is designed to measure the charge of cosmic rays ranging from protons to iron nuclei with excellent detection efficiency and charge resolution. We present the design and fabrication of the SCD as well as its performance during space environment tests which it underwent successfully. We also present its performance in charge measurement using heavy ions in a beam test at CERN, the European Organization for Nuclear Research.

The Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) instrument is a next-generation experiment for the direct detection and study of cosmic-ray nuclei and electrons. With a long exposure in low Earth orbit, the experiment will determine the particle fluxes and spectral details of cosmic-ray nuclei from hydrogen to iron, over an energy range of about 1 0 12 eV to > 1 0 15 eV, and of cosmic-ray electrons over an energy range of about 5 × 1 0 10 eV to > 1 0 13 eV. The instrument was deployed to the ISS in August 2017 on the SpaceX CRS-12 mission. We review the design, implementation and performance of one of the ISS-CREAM detector systems: a boron loaded scintillation detector used in discriminating electron-induced events from the much more abundant cosmic-ray nuclei.

International audience; The Cosmic Ray Energetics and Mass experiment at the International Space Station (ISS-CREAM) is developed for studying the origin, acceleration and propagation mechanism of high energy cosmic rays. The Top and Bottom Counting Detectors (TCD/BCD), sub-detectors of the ISS-CREAM instrument, are developed for electron/ γ -ray physics. The TCD/BCD help distinguish electrons from protons by comparing the hit and shower width distributions for electrons and protons. The e/p separation capability of the TCD/BCD is studied by using the GEANT3 simulation package, and optimal parameters for the e/p separation are obtained.

International audience; The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is scheduled for launch in 2017. It is designed to directly measure and identify theelemental composition of incident Galactic cosmic rays from a few hundred GeV to PeV energies.Such large energy range sensitivity is reached by using an electromagnetic sampling calorimeter(CAL) which measures the energy deposit of particle-induced showers. The CAL is composedof twenty layers of tungsten plates interleaved with scintillating fibers, and glued together usingepoxy-coated fiberglass to comply with space launch requirements. In August 2015, beam testmeasurements were performed at CERN to verify the performance of the CAL using layers ofepoxy-coated fiberglass placed between tungsten plates. The CAL response to electron and pionbeams and its performance are reported and compared with previous beam test configurations.

International audience; The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is a space-borne mission designed for the precision measurement of the energy and elemental composition of cosmic rays. It is scheduled to be launched and installed on the ISS in August 2017. The Silicon Charge Detector (SCD), placed at the top of the ISS-CREAM payload, consists of 4 layers. Each layer has 2688 silicon pixels and associated electronics arranged in such a fashion that its active detection area of 78 x 74 cm2 is free of any dead area. The foremost goal of the SCD is to efficiently and precisely measure the charge of cosmic rays passing through it. The 4-layer configuration was chosen to achieve the best precision in measuring the charge of cosmic rays within the constraints on the mass, volume and power allotted to it. The amount of material used for its support structure was minimized as well to reduce the chance of interactions of the cosmic ray within the structure. Given the placement of the SCD, its 4-layer configuration and the minimal amount of material in the cosmic-ray trajectory, the SCD is designed to measure the charge of cosmic rays ranging from protons to iron nuclei with excellent detection efficiency and charge resolution. We present the design and fabrication of the SCD. It successfully underwent space environment tests including vibration and thermal-vacuum qualification. We present the performance of the SCD during these tests, as well as its charge-measurement performance on the ground using cosmic muons and heavy ions in CERN beam tests.

International audience; The Cosmic-Ray Energetics And Mass (CREAM) instrument for the International Space Station (ISS) is a detector for studying the origin, acceleration and propagation mechanism of high-energy cosmic rays. The ISS-CREAM instrument is scheduled to launch in 2017 to the ISS. The Top and Bottom Counting Detectors (TCD/BCD) are designed for studying electron and gamma-ray physics. The TCD/BCD are composed of a plastic scintillator and an array of photodiodes The active detection areas of the TCD/BCD are 500 $\times$ 500 mm$^2$ and 600 $\times$ 600 mm$^2$, respectively. The TCD/BCD were completed in 2015 and passed the environmental tests for safety in a space environment. After finishing these tests, the TCD/BCD were integrated with the payload. The TCD is located between the carbon target of the ISS-CREAM instrument and the calorimeter, and the BCD is located below the calorimeter. The TCD/BCD can distinguish between electrons and protons by using the different shapes between electromagnetic and hadronic showers in the high-energy region. We study the TCD/BCD performance in various energy ranges by using GEANT3 simulation data. Here, we present the status of the electron and proton separation study with the TCD/BCD simulation.

International audience; The Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) instrument is designed and built to measure elemental spectra of cosmic-ray nuclei (1 ≤ Z ≤ 26) and electrons. It will measure energy of incident cosmic rays from 1011 to 10^15 eV with a tungsten/scintillator sampling calorimeter and densified carbon target with an interaction length of ~ 1 λL. A finely segmented, four-layer silicon charge detector will identify the elemental composition with a resolution of ~ 0.15e. The instrument is triggered by selectable, independent, and combined algorithms from the calorimeter and a scintillator-based counting detector on the top and bottom of the calorimeter. The counting detectors also provide separation of protons and electrons using differences in the shower shapes. A boronated scintillator detector provides additional e/p separation by looking at late scintillation light produced by a particle interacting in the calorimeter system. ISS-CREAM underwent vibrational, electromagnetic, thermal/vacuum, and telemetry systems tests at various NASA f acilities to qualify for rocket transportation and space operations. All testing and integration were completed and ISS-CREAM was delivered to NASA. It is now flight ready and waiting for launch on SpaceX-12 in 2017. ISS-CREAM integration, environmental qualification, and instrument performance will be presented.

International audience; The Boron And Carbon Cosmic rays in the Upper Stratosphere (BACCUS) balloon-borne exper-iment flew for 30 days over Antarctica in December 2016. It is the successor of the CREAMballoon program in Antarctica which recorded a total cumulative exposure of 161 days. BAC-CUS is primarily aimed to measure cosmic-ray boron and carbon fluxes at the highest energiesreachable with a balloon or satellite experiment, in order to provide essential information for abetter understanding of cosmic-ray propagation in the Galaxy. The payload is made of multipleparticle physics detectors which measure the charge up to Z=26 and energy of incident particlesfrom a few hundred GeV to a few PeV. The newly designed Transition Radiation Detector (TRD)measures signals that are a function of the charge and Lorentz factor. In April 2016, BACCUSwas taken to CERN in its flight configuration to characterize its detectors’ response to beams ofelectrons and pions. The performance of the TRD using beam test data are reported in this paper.

International audience; The Galactic 1.809-MeV γ-ray signature from the β decay of $^{26g}$Al is a dominant target of γ-rayastronomy, of which a significant component is understood to originate from massive stars. The$^{26g}$Al(p; γ)$^{27}$Si reaction is a major destruction pathway for $^{26g}$Al at stellar temperatures, but the reactionrate is poorly constrained due to uncertainties in the strengths of low-lying resonances in $^{27}$Si. The$^{26g}$Al(d; p)$^{27}$Al reaction has been employed in inverse kinematics to determine the spectroscopic factors,and hence resonance strengths, of proton resonances in $^{27}$Si via mirror symmetry. The strength of the127-keV resonance is found to be a factor of 4 higher than the previously adopted upper limit, and the upperlimit for the 68-keV resonance has been reduced by an order of magnitude, considerably constraining the$^{26g}$Al destruction rate at stellar temperatures.

The low intensity of the RIBS presently available at the first generation production facilities (10(5)-10(6) pps) and the necessity to reconstruct the event kinematics in RIB measurements require detection systems having both a large solid-angle coverage and a high granularity. The EXODET (EXOtic DETector) apparatus has been accomplished to respond to these requirements and the first experiment has been successfully performed studying the F-17 scattering on Pb-208 at 90.4 MeV.

A new pixel-structure detector array with a large solid angle coverage has been used for the first time to study the elastic scattering of exotic F-17 nuclei from a Pb-208 target at 90.4 MeV. The experimental data have been analyzed in the framework of the optical model potential and the real and imaginary strong absorption radii have been evaluated. These quantities have been compared with those obtained for the system F-19+Pb-208 at the same energy in the center of mass frame. The F-17+Pb-208 reaction cross section is more similar to those of the systems O-16,O-17+Pb-208 rather than to the one of the system F-19+Pb-208 at similar energies: this indicates that in the energy range around the Coulomb barrier the breakup channel is still weak. The exclusive breakup cross section F-17-->O-16+p has been measured for the first time at energy below the Coulomb barrier.

The extraction of detailed nuclear structure information from transfer reactions requires reliable, well-normalized data as well as optical potentials and a theoretical framework demonstrated to work well in the relevant mass and beam energy ranges. It is rare that the theoretical ingredients can be tested well for exotic nuclei owing to the paucity of data. The halo nucleus Be-11 has been examined through the 10Be(d,p) reaction in inverse kinematics at equivalent deuteron energies of 12,15,18, and 21.4 MeV. Elastic scattering of Be-10 on protons was used to select optical potentials for the analysis of the transfer data. Additionally, data from the elastic and inelastic scattering of Be-10 on deuterons was used to fit optical potentials at the four measured energies. Transfers to the two bound states and the first resonance in Be-11 were analyzed using the Finite Range ADiabatic Wave Approximation (FR-ADWA). Consistent values of the spectroscopic factor of both the ground and first excited states were extracted from the four measurements, with average values of 0.71(5) and 0.62(4) respectively. The calculations for transfer to the first resonance were found to be sensitive to the size of the energy bin used and therefore could not be used to extract a spectroscopic factor., 16 Pages, 10 figures

Atomic nuclei have a shell structure where nuclei with 'magic numbers' of neutrons and protons are analogous to the noble gases in atomic physics. Only ten nuclei with the standard magic numbers of both neutrons and protons have so far been observed. The nuclear shell model is founded on the precept that neutrons and protons can move as independent particles in orbitals with discrete quantum numbers, subject to a mean field generated by all the other nucleons. Knowledge of the properties of single-particle states outside nuclear shell closures in exotic nuclei is important for a fundamental understanding of nuclear structure and nucleosynthesis (for example the r-process, which is responsible for the production of about half of the heavy elements). However, as a result of their short lifetimes, there is a paucity of knowledge about the nature of single-particle states outside exotic doubly magic nuclei. Here we measure the single-particle character of the levels in 133Sn that lie outside the double shell closure present at the short-lived nucleus 132Sn. We use an inverse kinematics technique that involves the transfer of a single nucleon to the nucleus. The purity of the measured single-particle states clearly illustrates the magic nature of 132Sn., 19 pages, 5 figures and 4 tables

The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is predicted to be enhanced in reactions involving very neutron-rich unstable nuclei. Experimental measurements were carried out to investigate if it is feasible to use such beams to produce new heavy elements. The current status of these experimental activities is given in this review., Comment: 30 pages, 12 figures

The availability of fast radioactive beams offers the possibility for studies of E1‐strength in projectiles via Coulomb excitation. Theoretical calculations predict that a significant fraction of this strength is shifted towards lower excitation energies in neutron‐rich systems (e.g., [1]). At the NSCL, virtual photon scattering was used to probe the discrete structure of both 18O and 20O for levels in the region between 1 and 8 MeV. Two 1− levels at 5.35(10) and 6.85(5) MeV were observed for the first time in 20O [2]. The observed γ‐ray spectrum for 20O is, in fact, dominated by transitions resulting from E1 excitations to these states. The extracted B(E1) ↑ values of ∼0.062(16) e2fm2 and ∼0.035(9) e2fm2 for the 5.35 and 6.85 MeV levels, respectively, are larger than shell model calculations predict [3, 4]. Such large dipole strengths are not observed for low‐lying 1− states in 18O, indicating a shift of dipole strength towards lower energies as one approaches the neutron drip‐line.

We have studied the elastic scattering of the exotic F-17 nuclei from Pb-208 at Coulomb barrier energies. For the measurement we used a new detector array with pixel structure and a large solid angle. Optical potential analysis shows that F-17 has an imaginary potential much less deep than F-19. Information on the exclusive F-17 breakup cross section has been deduced too.