[en] The task of measuring a half-life of the order of 10²⁵ yr given only 10 kg of source material is being addressed by the NEMO 3 detector. The detector's primary radioanalysis involves the search for neutrinoless double-beta decay. Proposed in 1939, neutrinoless double-beta decay still remains unobserved. The NEMO 3 detector is being built by the international Neutrino Experiments with Molybdenum (NEMO) Collaboration, which currently consists of five countries and ten institutions. Similar to other high-energy physics detectors that employ multidetector systems, the NEMO 3 detector consists of a tracking volume and calorimeter with a cylindrical format. This large detector is enhanced with the use of ultralow radioactive components. The detector will operate underground in the Frejus tunnel in France at a depth of 4,800 meters water equivalent. The detector is mounted vertically and is divided into 20 equal sectors. A thin (40- to 50-microm) cylindrical source foil hangs between two concentric cylindrical tracking volumes that are 1 m deep and 3 m high. Tracking of low-energy electrons (lt4 MeV) is accomplished with 6,180 open octagonal drift cells operating in Geiger mode. These cells are mounted vertically, and events of interest tend to radiate horizontally from the source foil. Thus, the occasional cosmic ray muon fails to be a significant background. Surrounding the tracking volume are ,1940 scintillator blocks with either 3- or 5-in. photomultiplier tubes (PMTs) with energy resolutions of 14.5 and 11% full-width at half-maximum at 1 MeV, respectively. The activity of the 0.6 t of PMTs is three orders of magnitude below standard PMT levels, and the activity of the 5 t of scintillator is negligible relative to the PMTs

[en] The task of measuring a half-life of the order of 10²⁵ yr given only 10 kg of source material is being addressed by the NEMO 3 detector. The detector's primary radioanalysis involves the search for neutrinoless double-beta decay. Proposed in 1939, neutrinoless double-beta decay still remains unobserved

[en] The NEMO collaboration is in the final stages of completing a detector to search for neutrinoless double beta decay. The detector holds 10 kg of double-beta-decay isotopes allowing one to study the effective neutrino mass down to 0.1 eV. Three of the detector's sectors have been operating since June of 2000 to perform diagnostic tests on the track recognition, the calorimeter, and the software. The obtained results of these diagnostic tests are presented

[en] The NEMO collaboration is in the final stages of completing a detector to search for neutrinoless double-beta decay. The experiment is called NEMO 3 and came on line at the beginning of 2002. Located in the Frejus Underground Laboratory, the detector holds 10 kg of double-beta-decay isotopes, allowing one to study the effective neutrino mass down to approximately 0.1 eV. Thus, the detector has the potential to confirm physics beyond the Standard Model. Three of the detector's sectors have been operating since June 2000 to perform diagnostic tests on the track recognition, the calorimeter, and the software. The results of these diagnostic tests are presented with a discussion of the detector and source backgrounds

[en] The physics departments of a consortium of higher education in Western Massachusetts, the Five Colleges Incorporated, are developing an advanced undergraduate laboratory course. The participating institutions are Amherst College, Mount Holyoke College, Smith College, and the University of Massachusetts. The course is designed to expose students to a variety of state-of-the-art equipment that would normally exceed reasonable financial commitments and faculty expertise of a single institution. The course is divided into experimental modules, one of which is the cosmic ray muon decay module developed at Smith College. The module is designed to investigate the dependence of the muon lifetime as a function of the medium in which it decays. Useful background information and a description of the module is given in this article

[en] Twenty-two 5-mm-diameter intravascular endoprostheses of noncorrosive shape-memory titanium-nickel alloy were implanted transluminally in bilateral iliac (n = 18), femoral (n = 2), and carotid (n = 2) arteries of ten normal dogs for 0.5 to 24 months. The endoprostheses were widely patent for 1 month (19 of 20 dogs), 1 year (11 of 12 dogs), and 2 years (4 of 4 dogs). No migration, erosion, inflammation, surface thrombus, or stenosis of side branches were seen. No untoward angiographic or histopathologic effects were detected over 2 years. The neointima endothelialized completely within 2 months, remaining stable for 2 years (226.6 +- 160.5 μm). Satisfactory delivery, long-term function, and biocompatibility were observed for the endoprostheses

[en] We report the results of an experimental search for neutrinoless double-β decay using isotopically enriched foils of ¹⁰⁰Mo interleaved in a stack of 40 silicon detectors. With an exposure of 69.9 mole days, we place lower half-life limits on the J^P=0⁺→0⁺ transition of 4x10²¹ yr (68% C.L.) and on the 0⁺→2⁺ transition of 4x10²⁰ yr (68% C.L.)

[en] The proposed intense slow positron source (ISPS) at Idaho National Engineering Laboratory (INEL) requires focusing from a large area source to a small (1 cm) remoderator foil. A diameter reduction of >30 is desirable, and a gridless design appears to accommodate the design requirements. Experimental confirmation of the gridless focusing concept is presented here together with SIMION (simulated ion tracking) computer simulations, which indicate a diameter reduction of ∼50x

[en] No evidence for the neutrinoless double-β decay of ¹⁰⁰Mo has been found in a search using a segmented Si(Li) detector with source foils enriched to 97% ¹⁰⁰Mo. After 0.2664 mole years of exposure, we report a 1σ lower limit on the half-life for the J^P=0⁺→0⁺ transition of 0.44x10²³ years

[en] No evidence for the neutrinoless double-β decay of ¹⁰⁰Mo has been found in a search using a segmented Si(Li) detector with source foils enriched to 97% ¹⁰⁰Mo. From an exposure of 0.2664 mole years, and using Bayesian statistics to calculate confidence levels, we find a 68% lower limit on the half-life for the J^p=0⁺→0⁺ transition of 0.22x10²³ yr. The measured half-life of the two neutrino double-β decay is 0.76_-0.14^+0.22x10¹⁹ yr. copyright 1997 The American Physical Society