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The Cockcroft Beamline is being designed to transport 1 GeV electrons from a laser wakefield accelerator (LWFA) to an undulator at the Scottish Centre for the Application of Plasma-based Accelerators (SCAPA) in Glasgow, UK. To demonstrate undulator radiation in the X-ray spectral region and potentially free electron laser (FEL) gain, electrons should be transported between the LWFA and the undulators with high fidelity. In this paper we present the design of an adjustable beam line to transport LWFA electrons to the undulator for a range of energies, from 0.5 GeV to 1 GeV, while preserving the electron beam properties and matching the undulator-beam coupling., Proceedings of the 10th Int. Particle Accelerator Conf., IPAC2019, Melbourne, Australia

The Cockcroft Beamline is to be installed at the Scottish Centre for the Application of Plasma-based Accelerators (SCAPA). The beamline is designed to transport 1 GeV electrons from a laser wakefield acceleration (LWFA) source to a pair of transverse gradient undulators. The project aims to produce X-ray undulator radiation in the first phase and free-electron laser (FEL) radiation in the second phase. The total beamline will be less than 23 m long, thus the Cockcroft Beamline has the potential to be the UK's first compact X-ray FEL. Here we present the main features of the beamline design., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

Laser wakefield acceleration, together with other types of novel acceleration techniques, has seen considerable progress of late. Together with this progress comes a question, which has only recently started to be addressed, of how to transport and utilise such beams. This is a challenge because of the high initial divergence of these beams. There are several approaches to this problem and we concentrate on one in this paper and look at the implications of it in some detail., Proceedings of the 9th Int. Particle Accelerator Conf., IPAC2018, Vancouver, BC, Canada

In this paper the detailed structure of the transport beam line design is proposed, quadrupoles and deflectors specifications in order to transport the beam from the optic adaptation point in the SPIRAL2 production building up to the adaptation point in the DESIR hall. All optical elements, in beam line, are electrostatic and so, settings are independent of the ratio q/m of the particle. The calculations are done by COSY INFINITY computer code in first order of approximation and without fringe field effects. The beam emittances at the starting point (adaptation point in the SPIRAL2 production building) in horizontal and vertical planes are 80p mm mrad. The beam line is designed in such a way that the beam sizes, in both planes, at the end (adaptation point in the DESIR hall) are kept the same as they are at the starting point; the horizontal and vertical displacements from the optic axis at starting and ending points are the same, ±6 mm. In such case the efficiency of transport of the beam is high. [Projekat Ministarstva nauke Republike Srbije, br. OI-171018]

International audience; Production costs and energy efficiency are the main priorities for the photovoltaic (PV) industry (COP21 conclusions). To lower costs and increase efficiency, we are proposing to reduce the number of processing steps involved in the manufacture of N-type Passivated Rear Totally Diffused (PERT) silicon solar cells. Replacing the conventional thermal diffusion doping steps by ion implantation followed by thermal annealing allows reducing the number of steps from 7 to 3 while maintaining similar efficiency. This alternative approach was investigated in the present work. Beamline and plasma immersion ion implantation (BLII and PIII) methods were used to insert n-(phosphorus) and p-type (boron) dopants into the Si substrate. With higher throughput and lower costs, PIII is a better candidate for the photovoltaic industry, compared to BL. However, the optimization of the plasma conditions is demanding and more complex than the beamline approach. Subsequent annealing was performed on selected samples to activate the dopants on both sides of the solar cell. Two annealing methods were investigated soak and spike thermal annealing. Best performing solar cells, showing a PV efficiency of about 20%, was obtained using spike annealing with adapted ion implantation conditions.

DerVergleichvonTeilchenundAntiteilchenSystemenumdieCPT Symmetriezu testen ist heutzutage von intrinsischer Interesse f��r die Teilchenphysik. Ein interessantes System ist der Vergleich der Grundzustands-Hyperfeinstruktur von Wasserstoff mit Antiwasserstoff bei der Abwesenheit eines Magnetfeldes. Die ASACUSA Kollaboration strebt danachdiesenCPT TestmiteinemRabiSpektrometerAufbaudurchzuf��hren. Diese Arbeit beschreibt den Spektrometer Aufbau, welche bei den Antiwasserstoff Experimenten verwendet werden wird. Die einzelnen Komponenten wurden getestet und der gesamte Aufbau wurde mit atomaren Wasserstoff charakterisiert. Die wichtigsten Teile dieses Experiments waren eine atomare Wasserstoffquelle, ein kryogenisches Arrangement um den Strahl zu k��hlen, ein Strahl-Modulator, zwei polarisierende Sextupolmagnete, eine Mikrowellenkavit��t, welche die Spinzust��nde invertiert, einen supraleitenden Sextupolmagneten als Analysemagnet und ein Massenspektrometer. Ein zweiter sehr wichtiger Teil dieser Arbeit bestand darin die -1-��berg��nge, welche eine der f��r diese Kavit��t m��glichen messbaren ��berg��nge sind, zu analysieren. Wie gezeigt werden wird war es uns m��glich mit dieser Strahllinie den besten Wert f��r die Hyperfeinaufspaltung von atomaren Wasserstoff in einem Rabi-Experiment zu messen. Der gewonnene Wert f��r eine Frequenz -0 ist 1 420 405 748.9 �� 3.3stat �� 2.5sys Hz. Die Frequenz ist in ��bereinstimmung mit dem Wert von Masermessungen und ist mehr als eine Gr����enordnung besser als vorhergehende Rabi-Experimente aus den 1950ern. Dieses Resultat zeigt, dass mit Antiwasserstoff eine ��hnliche Genauigkeit erreicht werden kann, vorausgesetzt, dass ein Strahl mit vergleichbaren Eigenschaften bereit steht., Today comparisons of matter and antimatter systems to perform CPT tests are of intrinsic interest to the particle physics community. One interesting system is the comparison of the ground state hyperfine structure of hydrogen and antihydrogen at zero magnetic field. The ASACUSA collaboration aims to perform this CPT test with a Rabi-type spectrometer beam line. This work describes the spectrometer beam line which will be used for the antihydrogen experiments. The individual components were tested and the whole setup was characterised with atomic hydrogen. The most important sections in these experiments were an atomic hydrogen source, a cryogenic arrangement for beam cooling, a beam modulating chopper system, two polarising sextupole magnets to select a quantum state doublet, a microwave cavity to drive spin flips, a superconducting sextupole magnet as analysing magnet and a mass spectrometer as detector. A second essential part in this work was the analysis of the -1-transitions, one of the possible transitions that can be measured with our spin flip cavity. As will be shown we were able to measure and evaluate the best value ever for the hyperfine structure of atomic hydrogen in a Rabi like experiment with this beam line. The obtained quantity has a frequency of -0 = 1 420 405 748.9 �� 3.3 stat �� 2.5sys Hz. This value is in agreement with the value of maser measurements and is more than one order of magnitude better than previous Rabi experiments performed in the 1950s. This result shows that similar accuracies could be achieved with antihydrogen provided a beam with similar properties becomes available.

The two charge exchange reactions 14N(d, 2He)14C and 14N(3He, t)14O were studied with high resolution in order to identify the Gamow–Teller (GT) strength distribution starting from the ground state (g.s.) of 14N in the β− and β+ directions. The isospin symmetry in the A = 14 mass system is investigated. An overview of the main features of the experimental investigation is summarized here.

Thin self-supporting targets are indispensable in high energy-resolution studies using a magnetic spectrometer. However, nuclear targets of alkaline and alkaline-earth metal or halogen isotopes are not easily available. In order to produce thin target foils of these elements for the use in charge-exchange reactions, we take advantage of the fact that the stable isotopes of these elements have relatively small negative Q values, while 12 C and 16 O have large negative Q values. Therefore, even if organic compounds containing carbon and oxygen are used as supporting material, clean spectra on alkaline and alkaline-earth metal or halogen targets can be obtained up to the excitation energies of Q-value differences. A technique to produce thin foils of the chemical compounds Na 2 CO 3 , K 2 CO 3 , CaCO 3 and CaCl2 was developed using polyvinylalcohol as supporting material. Foils with a total thickness of 1– 2 mg / cm 2 were produced and used as targets in a ( 3 He ,t) reaction study at an incident energy of 420 MeV . Owing to the small contributions of energy-loss differences of beam and reaction products in such thin targets, a very good resolution of ΔE/E=7×10−5 was achieved in combination with a high-resolution magnetic spectrometer.

High-resolution spectrometers for both incident beams and scattered particles have been constructed at the K1.8 beam line of the Hadron Experimental Facility at J-PARC. A point-to-point optics is realized between the entrance and exit of QQDQQ magnets for the beam spectrometer. Fine-pitch wire chamber trackers and hodoscope counters are installed in the beam spectrometer to accept a high rate beam up to 107 Hz. The superconducting kaon spectrometer for scattered particles was transferred from KEK with modifications to the cryogenic system and detectors. A missing-mass resolution of 1.9 ± 0.1 MeV/c2 (FWHM) was achieved for the ∑ peaks of (π±, K+) reactions on a proton target in the first physics run of E19 in 2010.

A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

13 pages, 15 figures.-- Printed version published Jul 1, 2009., Measurements of inelastic proton scattering with high energy resolution at forward scattering angles including 0 degrees are described. High-resolution halo-free beams were accelerated by the cyclotron complex at the Research Center for Nuclear Physics. Instrumental background events were minimized using the high-quality beam. The remaining instrumental background events were eliminated by applying a background subtraction method. As a result, clean spectra were obtained even for a heavy target nucleus such as Pb-208. A high energy resolution of 20 keV (FWHM) and a scattering angle resolution of +/- 0.6 degrees were achieved at an incident proton energy of 295 MeV. (C) 2009 Elsevier B.V. All rights reserved., This work has been partly supported by the Grants-in Aid for Scientific Research no. 14740154 and 18540270 of the Ministry of Education, Culture, Sports, Science and Technology of Japan.

To study the Gamow-Teller (GT) transitions to the pf-shell nucleus Cu-64, the Ni-64(He-3,t)Cu-64 experiment was performed at the Research Center for Nuclear Physics (RCNP) Ring Cyclotron, Osaka, using a He-3 beam of 140 MeV/nucleon. The outgoing tritons were momentum analyzed by the Grand Raiden spectrometer at 0(degrees). A high energy resolution of 32 keV (full width at half-maximum) allowed the separation of individual levels in the excitation-energy region from 0 to 3.5 MeV. In addition to the ground state (gs), known to be a J(pi)=1(+) GT state, many low-lying states showed L=0 nature, suggesting that they are candidates for GT states. Because the GT strength B(GT) for the gs transition is known from the beta-decay measurement, the strengths for the excited states could be determined using the proportionality between the B(GT) and the reaction cross section extrapolated to q=0 momentum transfer. At higher excitation energies, the level density becomes high and the so-called GT giant resonance dominates the spectrum. The lower and the upper limits of the strength contained in this energy region were estimated. Our results show that less than 55% of the strength predicted by the Ikeda sum rule is located in the excitation-energy region from 0 to 17 MeV..

To study the Gamow-Teller (GT) transitions to the pf-shell nucleus Cu-64, the Ni-64(He-3,t)Cu-64 experiment was performed at the Research Center for Nuclear Physics (RCNP) Ring Cyclotron, Osaka, using a He-3 beam of 140 MeV/nucleon. The outgoing tritons were momentum analyzed by the Grand Raiden spectrometer at 0(degrees). A high energy resolution of 32 keV (full width at half-maximum) allowed the separation of individual levels in the excitation-energy region from 0 to 3.5 MeV. In addition to the ground state (gs), known to be a J(pi)=1(+) GT state, many low-lying states showed L=0 nature, suggesting that they are candidates for GT states. Because the GT strength B(GT) for the gs transition is known from the beta-decay measurement, the strengths for the excited states could be determined using the proportionality between the B(GT) and the reaction cross section extrapolated to q=0 momentum transfer. At higher excitation energies, the level density becomes high and the so-called GT giant resonance dominates the spectrum. The lower and the upper limits of the strength contained in this energy region were estimated. Our results show that less than 55% of the strength predicted by the Ikeda sum rule is located in the excitation-energy region from 0 to 17 MeV..

To study the Gamow-Teller (GT) transitions to the pf-shell nucleus Cu-64, the Ni-64(He-3,t)Cu-64 experiment was performed at the Research Center for Nuclear Physics (RCNP) Ring Cyclotron, Osaka, using a He-3 beam of 140 MeV/nucleon. The outgoing tritons were momentum analyzed by the Grand Raiden spectrometer at 0(degrees). A high energy resolution of 32 keV (full width at half-maximum) allowed the separation of individual levels in the excitation-energy region from 0 to 3.5 MeV. In addition to the ground state (gs), known to be a J(pi)=1(+) GT state, many low-lying states showed L=0 nature, suggesting that they are candidates for GT states. Because the GT strength B(GT) for the gs transition is known from the beta-decay measurement, the strengths for the excited states could be determined using the proportionality between the B(GT) and the reaction cross section extrapolated to q=0 momentum transfer. At higher excitation energies, the level density becomes high and the so-called GT giant resonance dominates the spectrum. The lower and the upper limits of the strength contained in this energy region were estimated. Our results show that less than 55% of the strength predicted by the Ikeda sum rule is located in the excitation-energy region from 0 to 17 MeV..

State of the art X-ray micro-computed tomography (micro-CT) of reservoir rock samples and cuttings allows reconstruction of the pore network with micrometric spatial resolution that is suitable for further petrophysical and fluid flow properties evaluation. Synchrotron tomographic beam lines, compared to conventional micro-CT systems, allow better 3D representation of the pore space. The digital rock volume is used for medial axis extraction and for 3D pore space morphological characterization (i.e. connectivity, pore-body/throat size, shape factors, etc.). The medial axis is generally derived by computed intensive digital-thinning operations for skeletonization of the digital rock volume. The alternative method we describe in this work, allows to extract the 3D centered and shortest paths to follow in order to go through the pore space from any given point to another one using simple and well-established mathematical methods. Even if we do not consider explicitly fluid flow, one path can be viewed as the streamline of the fastest fluid thread for laminar flow regime that a particle follows to go through the pore space from an intrusion point to an exiting point of the digital sample. The method is very fast, processing large voxel volumes in seconds, and it is also amenable to parallelization. The conductance of the irregular cross-sections of the throats is calculated with a fast finite element method (f.e.m.) that assumes fully developed laminar flow in axial direction. The network is solved as a linear system and the absolute permeability derived. The paper reports the results of application on real oil reservoir sandstone samples and shows the potential to predict petrophysical properties from rock material (i.e. drilling cuttings or crushed side wall cores) not suitable for conventional analyses.

Isospin symmetry is expected for the T-z=+/- 1 -> 0 isobaric analogous transitions in isobars with mass number A, where T-z is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A=50 isobars were determined from a high energy-resolution T-z=+1 -> 0, Cr-50(He-3,t)Mn-50 study at 0 degrees in combination with the decay Q value and lifetime from the T-z=-1 -> 0, Fe-50 ->Mn-50 beta decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

A C-14(He-3,t)O-14 experiment was performed using a He-3 beam with E=140 MeV/nucleon. The achieved resolution of 33 keV (full width at half maximum) for the small scattering angle spectrum allowed the determination of the widths of several levels up to an excitation energy of 11.5 MeV. The width of the E-x=5.17 MeV,J(pi)=1(-) level was in good agreement with the known value, while for other states considerably improved or new results were obtained.

A C-14(He-3,t)O-14 experiment was performed using a He-3 beam with E=140 MeV/nucleon. The achieved resolution of 33 keV (full width at half maximum) for the small scattering angle spectrum allowed the determination of the widths of several levels up to an excitation energy of 11.5 MeV. The width of the E-x=5.17 MeV,J(pi)=1(-) level was in good agreement with the known value, while for other states considerably improved or new results were obtained.

Under the assumption that isospin T is a good quantum number, isobaric analog states and various analogous transitions are expected in isobars with mass number A. The, strengths of T-z = +/-3/2 --> 1/2 analogous Gamow-Teller (GT) transitions and analogous M1 transitions within the A = 41 isobar quartet are compared in detail. The T-z = +3/2 --> +1/2 GT transitions from the J(pi) = 3/2(+) ground state of K-41 leading to excited J(pi) = 1/2(+), 3/2(+), and 5/2(+) states in Ca-41 were measured using the (He-3, t) charge-exchange reaction. With a high energy resolution of 35 keV, many fragmented states were observed, and the GT strength distribution was determined up to 10 MeV excitation energy (E-x). The main part of the strength was concentrated in the E-x = 4-6 MeV region. A shell-model calculation could reproduce the concentration, but not so well details of the strength distribution. The obtained distribution was further compared with two results of Ti-41 beta decay studying the analogous T-z = -3/2 --> -1/2 GT strengths. They reported contradicting distributions. One-to-one correspondences of analogous transitions and analog states were assigned up to E-x = 6 MeV in the comparison with one of these Ti-41 beta-decay results. Combining the spectroscopic information of the analog states in Ca-41 and Sc-41, the most probable J(pi) values were deduced for each pair of analog states. It was found that 5/2(+) states carry the main part of the observed GT strength, while much less GT strength was carried by 1/2(+) and 3/2(+) states. The gross features of the GT strength distributions for each J were similar for the isospin analogous T-z = +/-3/2 --> +/-1/2 transitions, but the details were somewhat different. From the difference of the distributions, isospin-asymmetry matrix elements of 8 keV were deduced. The Coulomb displacement energy, which is sensitive to the configuration of states, showed a sudden increase of about 50 keV at the excitation energy of 3.8 MeV. The strengths of several M1 transitions to the IAS in Ca-41 were compared with the strengths of analogous GT transitions. It was found that ratios of the M1 and GT transition strengths were similar, suggesting that the contributions of the ltau term in M1 transitions are small.

Under the assumption that isospin T is a good quantum number, isobaric analog states and various analogous transitions are expected in isobars with mass number A. The, strengths of T-z = +/-3/2 --> 1/2 analogous Gamow-Teller (GT) transitions and analogous M1 transitions within the A = 41 isobar quartet are compared in detail. The T-z = +3/2 --> +1/2 GT transitions from the J(pi) = 3/2(+) ground state of K-41 leading to excited J(pi) = 1/2(+), 3/2(+), and 5/2(+) states in Ca-41 were measured using the (He-3, t) charge-exchange reaction. With a high energy resolution of 35 keV, many fragmented states were observed, and the GT strength distribution was determined up to 10 MeV excitation energy (E-x). The main part of the strength was concentrated in the E-x = 4-6 MeV region. A shell-model calculation could reproduce the concentration, but not so well details of the strength distribution. The obtained distribution was further compared with two results of Ti-41 beta decay studying the analogous T-z = -3/2 --> -1/2 GT strengths. They reported contradicting distributions. One-to-one correspondences of analogous transitions and analog states were assigned up to E-x = 6 MeV in the comparison with one of these Ti-41 beta-decay results. Combining the spectroscopic information of the analog states in Ca-41 and Sc-41, the most probable J(pi) values were deduced for each pair of analog states. It was found that 5/2(+) states carry the main part of the observed GT strength, while much less GT strength was carried by 1/2(+) and 3/2(+) states. The gross features of the GT strength distributions for each J were similar for the isospin analogous T-z = +/-3/2 --> +/-1/2 transitions, but the details were somewhat different. From the difference of the distributions, isospin-asymmetry matrix elements of 8 keV were deduced. The Coulomb displacement energy, which is sensitive to the configuration of states, showed a sudden increase of about 50 keV at the excitation energy of 3.8 MeV. The strengths of several M1 transitions to the IAS in Ca-41 were compared with the strengths of analogous GT transitions. It was found that ratios of the M1 and GT transition strengths were similar, suggesting that the contributions of the ltau term in M1 transitions are small.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.

After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5 MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0degrees having a strong selectivity for Gamow-Teller transitions. In the comparison with the analogous M1 transitions in Mg-25, the J(pi)=3/2(+) bandhead state and the excited 5/2(+) and 7/2(+) members were clearly assigned.

After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5 MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0degrees having a strong selectivity for Gamow-Teller transitions. In the comparison with the analogous M1 transitions in Mg-25, the J(pi)=3/2(+) bandhead state and the excited 5/2(+) and 7/2(+) members were clearly assigned.

After 50 years of its prediction, the highest-lying [2 0 2]3/2 orbit among the six Nilsson single-particle orbits originating from the sd shells in prolately deformed nuclei and the rotational band on this orbit were identified. The band members were observed in Al-25 at excitation energies of 6-7.5 MeV in a high-resolution Mg-25(He-3,t) charge-exchange reaction at 0degrees having a strong selectivity for Gamow-Teller transitions. In the comparison with the analogous M1 transitions in Mg-25, the J(pi)=3/2(+) bandhead state and the excited 5/2(+) and 7/2(+) members were clearly assigned.

The mirror nuclei Mg-25 and Al-25 are expected to have very similar structures. The Gamow-Teller (GT) transitions from the J(pi) = 5/2(+) ground state of Mg-25 to the excited states in Al-25 were studied by high-resolution measurements of the Mg-25(He-3,t) charge-exchange reaction at 0degrees and at 140 MeV/nucleon. Assuming the usual DeltaJ(pi) = 1(+) selection rule for the spin-isospin-type GT transitions, the states with J(pi) = 3/2(+), 5/2(+), and 7/2 (+) should be excited. However, of the more than ten states with these J(pi) values below 6 MeV excitation energy, only the 5/2 (+) ground state and the 7/2 (+) , 1.613 MeV state in Al-25 were strongly populated, while all other states were strongly suppressed. The analysis of M1 transitions in Mg-25 also suggested a very similar feature for the analogous M1 transitions. Both Mg-25 and Al-25 are known to be largely deformed, and most low-lying states can be interpreted in terms of one-particle quantum numbers in the deformed potential and the associated rotational spectra. The observed suppression can be explained in terms of the K quantum number selection rules that are inherent to axially deformed nuclei.

International audience; In order to make a better use of the higher beam intensities soon available at GANIL, a proposal called SISSI was presented in 1989. It consists of a set of two superconducting solenoid lenses of very short focal length (0.6 m). The fist solenoid is used to sharply focus the incoming beam on a fast moving target. The second increases the angular acceptance of the beam line downstream the target for charged reaction products. Calculations show that from a 0.4-mm-diameter beam spot on the target, an acceptance angle of up to 80 mrad will be reached without significant emittance growth due to aberration effects. Technical aspects of that project are presented

The Low Density Matter (LDM) beamline has been built as part of the FERMI free-electron laser (FEL) facility to serve the atomic, molecular and cluster physics community. After the commissioning phase, it received the first external users at the end of 2012. The design and characterization of the LDM photon transport system is described, detailing the optical components of the beamline.