[en] The double β decays of ¹⁰⁰Mo and ¹⁵⁰Nd were studied in a time projection chamber located 72 m underground. A 3275-h exposure of a 16.7-g sample of metallic Mo enriched to 97.4% in ¹⁰⁰Mo resulted in a two-neutrino half-life, T_1/2^2ν=(6.82_-0.53^+0.38±0.68)x10¹⁸y. Similarly, a 6287-h exposure of 15.5 g of Nd₂O₃ enriched to 91% in ¹⁵⁰Nd yielded T_1/2^2ν=(6.75_-0.42^+0.37±0.68)x10¹⁸y. Lower limits on half-lives for neutrinoless decay with and without majoron emission also have been measured. copyright 1997 The American Physical Society

[en] The aim of this study is to analyse an effective wavelet method for denoising and tracking temporal variations of the auditory brainstem response (ABR). The rapid and accurate extraction of ABRs in clinical practice has numerous benefits, including reductions in clinical test times and potential long-term patient monitoring applications. One method of achieving rapid extraction is through the application of wavelet filtering which, according to earlier research, has shown potential in denoising signals with low signal-to-noise ratios. The research documented in this paper evaluates the application of three such wavelet approaches on a common set of ABR data collected from eight participants. We introduced the use of the latency–intensity curve of ABR wave V for performance evaluation of tracking temporal variations. The application of these methods to the ABR required establishing threshold functions and time windows as an integral part of the research. Results revealed that the cyclic-shift-tree-denoising performed superior compared to other tested approaches. This required an ensemble of only 32 epochs to extract a fully featured ABR compared to the 1024 epochs with conventional ABR extraction based on linear moving time averaging

[en] The false setting is when cement stiffens prematurely in a few minutes after adding water. Some variables could cause false setting in CPI-S-32 Portland cement, for example, alkali concentration in the cement, the formation of alite (C₃S) with low reactivity, and cement storage temperature and time in silos. Temperature increases cause calcium sulfate dihydrate to dehydrate, forming hemihydrate (CaSO₄.0.5H₂O) or anhydrite (CaSO₄ ), which causes the false setting. In this study, the influence of cement storage temperature (100, 105, 110, 120, and 130 °C) combined with the cement storage time (30, 60, and 120 min) in a silo was studied regarding the CPI-S-32 false setting behavior. It was verified that temperatures above 110 °C and storage time above 60 min are conditions that favor the false setting of CPI-S-32 cement. Physicochemical analysis, TG/DTG, XRF, and XRD were applied as complementary analyzes for the false setting assays of CPI-S-32. (author)

[en] The ATLAS collaboration is managing one of the largest collections of software among the High Energy Physics experiments. Traditionally, this software has been distributed via rpm or pacman packages, and has been installed in every site and user's machine, using more space than needed since the releases share common files but are installed in their own trees. As soon as the software has grown in size and number of releases this approach showed its limits, in terms of manageability, used disk space and performance. The adopted solution is based on the CernVM File System, a fuse-based HTTP, read-only filesystem which guarantees file de-duplication, on-demand file transfer with caching, scalability and performance. Here we describe the ATLAS experience in setting up the CVMFS facility and putting it into production, for different type of use-cases, ranging from single users’ machines up to large data centers, for both software and conditions data. The performance of CernVM-FS, both with software and condition data access, will be shown, comparing with other filesystems currently in use by the collaboration.

[en] An all-optical, near-resonant laser atom trap is used to prepare an electronically excited and polarized gas target at mK-temperature for complete photo-ionization studies. As a proof-of-principal experiment, lithium atoms in the 2²P_3/2(m _l = +1) state are ionized by a 266 nm laser source, and emitted electrons and Li⁺ ions are momentum analyzed in a COLTRIMS spectrometer. The excellent resolution achieved in the present experiment allows not only to extract the relative phase and amplitude of all partial waves contributing to the final state, it also enables to characterize the experiment regarding target and spectrometer properties. Photo-electron angular distributions are measured for five different laser polarizations and described in a one-electron approximation with excellent agreement. (paper)

[en] ⁴⁸Ca, the lightest experimentally accessible double beta decay candidate, is the only one simple enough to be treated exactly in the nuclear shell model. Thus the ββ_2ν half-life measurement, reported here, provides a unique test of the nuclear physics involved in the ββ matrix element calculation. Enriched ⁴⁸Ca sources of two different thicknesses have been exposed in a time projection chamber. We observe a half-life of T_1/2^2ν=(4.3_-1.1^+2.4[stat]±1.4[syst])x10¹⁹ yr, consistent with shell model calculations. copyright 1996 The American Physical Society

[en] A novel molecular AND logic gate 1 is demonstrated based on the competition between fluorescence and photoinduced electron transfer (PET). It is constructed according to a 'receptor₂-spacer-fluorophore-spacer-receptor₁-spacer-fluorophore -spacer-receptor₂' format where receptor₁ is a tertiary amine, receptor₂ is a benzo-15-crown-5 ether and the fluorophore is an anthracene moiety, which are separated from each other by methylene spacers. The fluorescence response in methanol is significantly enhanced only when both H⁺ and Na⁺ are the inputs at high enough concentrations in accordance with AND logic. Cs⁺ behaves similarly to Na⁺, but with a lower fluorescence enhancement, whereas the other alkali metal cations are not effective. Electrospray ionization mass spectrometry provides evidence for formation of 1:1 and 1:2 (1:metal) complexes with alkali cations, and formation of a 1:2:1 (1:metal:proton) complex in the additional presence of acid

[en] ⁴⁸Ca is the lightest of the many double beta decay nuclei, and the only one simple enough to be treated exactly in the shell model without truncation. Thus a ββ_2ν measurement of this isotope provided a unique test of the nuclear physics involved in ββ matrix element calculations. Enriched ⁴⁸Ca sources of two different thicknesses have been exposed in a time projection chamber, and yield a preliminary T_1/2^2ν=(5.5^+3.5_-1.5).10¹⁹ y in agreement with shell model calculations. (orig.)

[en] In the energy region 10 - 100 TeV both the c.r. composition from direct measurements and the cross section for high energy secondary production in the very forward region for p-air interactions are rather uncertain. Contemporaneous measurements of the total energy and of the threshold energy/nucleon of the primary particle can be provided by the atmospheric Cherenkov light and high energy muons. These measurements are performed by the combined operation of the Cherenkov array of the EAS-TOP experiment on the surface (810 gcm² atmospheric depth) and of the LVD experiment in the underground Gran Sasso Laboratories (3300 m w.e.; E^th_μ = 1.3 TeV) leading to the measurement of < N_μ > (E_μ > 1.3 TeV, E₀) in the given energy range. The combined operation of the experiments and preliminary results are reported