Radiometry with synchrotron radiation at the PTB laboratory at Bessy ii

A workshop on Engineering Applications of Neutrons and Synchrotron Radiation took place on September 13–14, 2004, at the ESRF in Grenoble, France. The workshop brought together around 100 leading scientists and engineers who discussed the application of synchrotron X-ray and neutron central facilities for engineering problems. The event was organized by the FaME38 materials engineering facility at ILL-ESRF. FaME38 is jointly funded by the UK research council EPSRC and ILL-ESRF and provides support to enable materials engineers to make the best use of the advanced synchrotron X-ray and neutron scientific facilities at ILL-ESRF.

The programme included formal presentations, a poster session, informal workgroup sessions and an opportunity to meet staff at the ILL-ESRF materials science beamlines. The formal presentations were structured into three sessions entitled Progress, Complementarity, and Applications chaired by Giovanni Bruno (ILL), Thomas Buslaps (ESRF), and Darren Hughes (FaME38).     

Radiochemical studies at the cyclotron laboratory, Tohoku university

In order to achieve a progressive experimental program, a new system for radioisotope production has been developed at one of the beam-courses of a multipurpose Cyclotron of K=110 MeV. The upgraded beam-course is useful for the study of the nuclear physics and chemistry of heavy elements, radiopharmaceutical studies, the production of radioactive tracers, activation analysis using charged particles, etc. Several topics are demonstrated in the field of radioanalytical and nuclear studies.     

Activities in the IAEA X‐ray fluorescence laboratory at Seibersdorf

This paper describes the specific philosophy behind the functioning of the IAEA XRF Laboratory at Seibersdorf and its role in the XRF community. Some examples of the research and development activities and the results obtained are given. They include methodological development and construction of XRF instruments in order to extend the applicability range of the XRF technique, particularly in support of applications of the analytical technique in developing IAEA member states. The contribution of the laboratory to the training in methodology and applications of XRF techniques and to development of QA/QC procedures is also emphasised. Copyright © 2006 John Wiley & Sons, Ltd.     

Progress in direct-drive inertial confinement fusion research at the laboratory for laser energetics

Direct-drive inertial confinement fusion (ICF) is expected to demonstrate high gain on the National Ignition Facility (NIF) in the next decade and is a leading candidate for inertial fusion energy production. The demonstration of high areal densities in hydrodynamically scaled cryogenic DT or D₂ implosions with neutron yields that are a significant fraction of the “clean” 1-D predictions will validate the ignition-equivalent direct-drive target performance on the OMEGA laser at the Laboratory for Laser Energetics (LLE). This paper highlights the recent experimental and theoretical progress leading toward achieving this validation in the next few years. The NIF will initially be configured for X-ray drive and with no beams placed at the target equator to provide a symmetric irradiation of a direct-drive capsule. LLE is developing the “polar-direct-drive” (PDD) approach that repoints beams toward the target equator. Initial 2-D simulations have shown ignition. A unique “Saturn-like” plastic ring around the equator refracts the laser light incident near the equator toward the target, improving the drive uniformity. LLE is currently constructing the multibeam, 2.6-kJ/beam, petawatt laser system OMEGA EP. Integrated fast-ignition experiments, combining the OMEGA EP and OMEGA Laser Systems, will begin in FY08.     

New measurements of G using the measurement standards laboratory torsion balance

This Letter presents the results of a series of measurements of the Newtonian gravitational constant G using the compensated torsion balance developed at the Measurement Standards Laboratory. Since our last published result using the torsion balance in the compensated mode of operation [Meas. Sci. Technol. 10, 439 (1999)]], several improvements have been made to reduce the uncertainty in the final result. The new measurements have used both stainless steel and copper large masses. The values of G for the two sets of masses are in good agreement. After combining all of the measurements we get a value of G=6.673 87(0.000 27) x 10(-11) m3 kg(-1) s(-2). This new value is 5 parts in 10(5) smaller than our previous published values.     

New limits on the drift of fundamental constants from laboratory measurements

We have remeasured the absolute 1S-2S transition frequency nu(H) in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (-29+/-57) Hz for the drift of nu(H) with respect to the ground state hyperfine splitting nu(Cs) in 133Cs. Combining this result with the recently published optical transition frequency in 199Hg+ against nu(Cs) and a microwave 87Rb and 133Cs clock comparison, we deduce separate limits on alpha/alpha=(-0.9+/-2.9) x 10(-15) yr(-1) and the fractional time variation of the ratio of Rb and Cs nuclear magnetic moments mu(Rb)/mu(Cs) equal to (-0.5+/-1.7) x 10(-15) yr(-1). The latter provides information on the temporal behavior of the constant of strong interaction.     

Monaural and binaural parameters of Rudolfinum concert halls in Prague

Objective parameters for the evaluation of the Rudolfinum concert hall in Prague, Czech Republic are the focus of the present article. The measured results for Reverberation parameters, Energy parameters, Intelligibility parameters, and Spatial parameters of the building’s two halls are presented and discussed including a comparison with recommended values or theory, as well as several unique architectural and acoustical qualities of the halls. The early lateral energy fraction parameter is measured by the intensity probe method discussed in the supplement. The performance is verified by tests in anechoic and reverberant rooms.     

平衡环境型房间量热计试验室的研制

依据国家标准GB/T7725 - 2004的技术要求,研制设计并建造了一套平衡环境型房间量热计试验室.研究测试结果表明,该试验室能够以较高的控制精度,并较快的达到所需的稳定工况,满足了测试0 ～ 5HP的房间空调器的要求.     

Comparative measurements of thermal neutron fluxes at ground level at the baksan neutrino observatory and LGNS laboratory

Thermal neutron fluxes were measured using two types of scintillation detectors based on the inorganic scintillator ZnS(Ag): ⁶LiF+ZnS(Ag) and ¹⁰B₂O₃ + KCl+ZnS(Ag). The preliminary results from these measurements are given. The thermal neutron concentration as a function of altitude above sea level was determined. The measurements were performed at three locations: in Moscow, at the Baksan Neutrino Observatory of the Russian Academy of Sciences, and at the Gran Sasso National Laboratory. Variations of neutron count rates associated with lunar cycles were observed at the remote laboratories.     

New look at the large numbers

A new interpretation for the large number hypothesis is given, referring to the close connection between the Bekenstein-Hawking entropy and Weizsäckers ur theory.     

Emission of electromagnetic waves at frequencies around twice the plasma frequency in a laboratory plasma

Electromagnetic waves at frequencies around twice the plasma frequency have been observed in a laboratory plasma.     

Search for supermassive magnetic monopoles with the MACRO detector at the gran sasso laboratory

We present the results of the search for supermassive magnetic monopoles with the MACRO experiment. Our detector is equipped with three independent subdetectors (liquid scintillation counters, limited streamer tubes and nuclear track detectors), operating in different ranges of monopole velocity. In several years of data taking no candidates were found; the present flux upper limits are the level of half the Parker Bound for β > 10⁻⁴; for 10⁻⁴ < β < 5 × 10⁻² the limit is the best existing.     

Doppler spectra of laboratory wind waves at low grazing angle

Eight radar frequencies over a range from 3 GHz to 94 GHz have been used to measure Doppler spectra of wind waves in a laboratory wind-wave tank, at low grazing angle. The VV spectra show relatively little change in shape at different frequencies. The HH spectra show significant trends in the lower radar frequencies, some of which are probably artefacts of the experiment. A new model, the 'fish model' is developed empirically from measurements of the peak Doppler spectra for both vertical and horizontal polarization. This model indicates that the H-pol, not just the V-pol, peak Doppler shift is dependent on the radar frequency.