61 research outputs found

    Proton-deuteron radiative capture cross sections at intermediate energies

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    Differential cross sections of the reaction p(d,3He)γp(d,^3{\rm He})\gamma have been measured at deuteron laboratory energies of 110, 133 and 180 MeV. The data were obtained with a coincidence setup measuring both the outgoing 3^3He and the photon. The data are compared with modern calculations including all possible meson-exchange currents and two- and three- nucleon forces in the potential. The data clearly show a preference for one of the models, although the shape of the angular distribution cannot be reproduced by any of the presented models.Comment: 6 pages, 6 figures, accepted for publication in EPJ

    Wages in high-tech start-ups - do academic spin-offs pay a wage premium?

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    Due to their origin from universities, academic spin‐offs operate at the forefront of the technological development. Therefore, spin‐offs exhibit a skill‐biased labour demand, i.e. spin‐offs have a high demand for employees with cutting edge knowledge and technical skills. In order to accommodate this demand, spin‐offs may have to pay a relative wage premium compared to other high‐tech start‐ups. However, neither a comprehensive theoretical assessment nor the empirical literature on wages in start‐ups unambiguously predicts the existence and the direction of wage differentials between spin‐offs and non‐spin‐offs. This paper addresses this research gap and examines empirically whether or not spin‐offs pay their employees a wage premium. Using a unique linked employer‐employee data set of German high‐tech start‐ups, we estimate Mincer‐type wage regressions applying the Hausman‐Taylor panel estimator. Our results show that spin‐offs do not pay a wage premium in general. However, a notable exception from this general result is that spin‐offs that commercialise new scientific results or methods provide higher wages to employees with linkages to the university sector – either as university graduates or as student workers

    Single Pass Stripline Beam Position Monitor Design, Fabrication and Commissioning

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    To monitor the position of the electron beam during transport from the Booster Synchrotron to the Storage Ring at the Australian Synchrotron, a stripline Beam Position Monitor (BPM) has been designed, fabricated and installed in-house. The design was based on an existing stripline in the Booster and modified for the transfer line with a particular emphasis on ensuring the line impedance is properly matched to the detector system. The initial bench tests of a prototype stripline showed that the fabrication of the four individual striplines in the BPM was made precisely, each with a measured standing wave ratio (SWR) of 1.8 at 500 MHz. Further optimization for impedance matching will be done for new stripline BPMs. The linearity and gain factor was measured with the detector system. The detector system that digitizes the signals is an Instrumentation Technologies Brilliance Single Pass [1]. The results show an error of 1 mm at an offset (from the electrical centre) of 10 mm when a linear gain factor is assumed and an RMS noise of ~150 um that decreases to < 10 um with increasing signal intensity. The results were under our requirements for the transport line. The commissioning results of the stripline will also be presented showing a strong signal for an electron beam with an estimated integrated charge of ~50 nC with a position stability of 28 um (horizontal) and 75 um (vertical)

    Injection Efficiency Monitor for the Australian Synchrotron

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    The Australian Synchrotron AS is moving towards a continuous injection mode called top-up. During top-up the linac and booster synchrotron injection system will be in continuous operation rather than usedevery eight hours the way they are used at present. In order to monitor the performance of the injection system areal-time injection efficiency monitoring system has been developed. The system consists of several Fast CurrentTransformers [1] and matching digitisers [2] and is designed to count every beam pulse and measure the transmission efficiency through the whole accelerator complex. After calibrating the system using a properly matchedFaraday Cup at the electron gun, a transmission efficiency is then calculated at each stage of transferring the beamfrom 90 keV out of the gun to 3 GeV in the storage ring. The system is used to optimise the injection process inorder to maximise the injection efficiency and as an early warning system when equipment starts to fail and theinjection efficiency decreases

    Injection Efficiency Monitor for the Australian Synchrotron

    No full text
    The Australian Synchrotron AS is moving towards a continuous injection mode called top-up. During top-up the linac and booster synchrotron injection system will be in continuous operation rather than usedevery eight hours the way they are used at present. In order to monitor the performance of the injection system areal-time injection efficiency monitoring system has been developed. The system consists of several Fast CurrentTransformers [1] and matching digitisers [2] and is designed to count every beam pulse and measure the transmission efficiency through the whole accelerator complex. After calibrating the system using a properly matchedFaraday Cup at the electron gun, a transmission efficiency is then calculated at each stage of transferring the beamfrom 90 keV out of the gun to 3 GeV in the storage ring. The system is used to optimise the injection process inorder to maximise the injection efficiency and as an early warning system when equipment starts to fail and theinjection efficiency decreases

    Proton-proton bremsstrahlung cross-sections including the kinematical singularity

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    Integrated cross-section data for proton-proton bremsstrahlung including the points with the phase-space singularity, which occurs close to the maximum non-coplanarity angle, are presented. A numerical integration of theoretical cross-sections is performed over the non-coplanarity angle to integrate out this singularity. Furthermore, a comparison is made between measured cross-sections and predictions of two soft-photon models. All features observed for the data far from the singularity, including the overestimation of the cross-section by approximate to 30% by the theoretical calculations, emerge as well for the data close to and including the singularity
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