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A number of recent studies have highlighted the scientific benefits of penetrator technology in conducting exploration on other planetary bodies and moons within the solar system. Such a "hard landing" approach is lower cost and simpler than the traditional "soft landing" method. However it is necessary for the science package of such a mission to withstand the rapid decelerations that will occur upon impact. This paper outlines an approach that has been developed to simulate the loading appropriate to Europa and also to monitor component performance before, during and after the impact. [ABSTRACT FROM AUTHOR]

The XMaS beamline at the ESRF has been in regular user operation since April 1998 and operates over an energy range of 2.4–15 keV. It has developed a wide range of unique instrumentation, primarily dedicated to high resolution magnetic and single crystal diffraction. With the upcoming ESRF upgrade program a number of instrumental developments are planned for the beamline to maximize the benefits of the increased photon flux at low energies. Firstly we report on the optimisation of the beamline and its core components. A novel attenuator system which is actuated by fast acting solenoids thereby avoiding problems of gas bursts into the beamline vacuum seen on some commercially available instruments is introduced. Secondly we discuss developments to the low temperature sample environments that have been integrated into the beamline vacuum system, minimizing both air and beryllium absorption. Finally we demonstrate the current capabilities of the beamline by describing preliminary reflectivity measurements that have been made on an [Fe(2ML)Pd(15ML)]x20 multilayer recorded around the Pd L3 edge using circular polarised light produced from a thin diamond phase plate. [ABSTRACT FROM AUTHOR]

X-ray Magnetic Circular Dichroism (XMCD) spectra from a 5 μm polycrystalline Gd foil were measured in transmission across the Gd L2,3 edges using the Multipurpose Unit for Synchronisation, Sequencing and Triggering (MUSST) card developed at the European Synchrotron Radiation Facility (ESRF). The circularly polarized x-rays were produced by a diamond phase-plate and their helicity was rapidly reversed through the use of a piezo driven device. The signal measured for each helicity was recorded by the MUSST card synchronized to the helicity reversal. The results are compared to those obtained using an analogue lock-in technique. [ABSTRACT FROM AUTHOR]

We report here on a number of developments that include enhancements of the sample environment on the XMaS beamline and the flux available at low energy. A 4 Tesla superconducting magnet has been designed to fit within the Euler cradle of a six circle Huber diffractometer, allowing scattering in both horizontal and vertical planes. The geometry of the magnet allows the application of longitudinal, transverse horizontal, and vertical fields. A further conventional magnet (∼ 0.1 T) to minimize air absorption at low energies (∼ 3KeV) has been designed for two circle applications, such as reflectivity. A novel in-vacuum slit screen has been developed, also minimizing absorption at low energies. New equipment for performing in-situ studies of surfaces in the electrochemical environment has been developed to allow control of the solution and sample temperature over the region of -5C to 80C. Preliminary experiments on the surface reconstructions of Au(111) in an electrolyte have been performed, whilst commissioning at the same time a MAR CCD detector for the beamline. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A compact, cryogen-free 0.5 Tesla superconducting Magnetic Resonance Imager (MRI) magnet has been conductively-cooled using a two-stage Pulse Tube cryo-refrigerator. With the absence of cold moving parts and seals, Pulse Tube cryo-refrigerators offer lower transmitted vibrations to a MRI magnet and potentially longer MTBF rates. A 7 kW input power compressor package was connected to the Pulse Tube. The Pulse Tube system provided an estimated 1.3 Watts of cooling power at 4.2 K. Vibration measurements made on the vacuum enclosure could not detect vibration or noise due to cryo-refrigerator operation even in the presence of very low levels of background noise. The cryo-refrigerator has been in continuous operation for >4000 hours without degradation of thermal performance. [ABSTRACT FROM AUTHOR]

The RHIC Loss Monitor System (BLM) was successfully commissioned during the RHIC (Relativistic Heavy Ion Collider) Year 0 Run (summer of 1999). The system consists of 363 argon ionization detectors distributed around the ring. The signals are digitized in a distributed multiplexed ADC system and displayed at a 1 Hz rate in the control room. During the commissioning, the beam loss monitor system was extensively used for first turn beam steering. An impressive example of the capabilities of this system was the ability to locate a thin obstruction to within one magnet length, even though this obstruction transmitted most of the beam. With this information we were able to achieve circulating beam. This paper will discuss the RHIC beam loss monitor system design and testing. The data acquired during the RHIC commissioning run will also be presented. [ABSTRACT FROM AUTHOR]