17 research outputs found

    Fragmentation of very high energy heavy ions

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    A stack of CR39 (C12H18O7)n nuclear track detectors with a Cu target was exposed to a 158 A GeV lead ion beam at the CERN-SPS, in order to study the fragmentation properties of lead nuclei. Measurements of the total, break-up and pick-up charge-changing cross sections of ultrarelativistic Pb ions on Cu and CR39 targets are presented and discussed.Comment: 4 pages, 3 EPS figures included with epsf, uses article.sty Talk presented by M. Giorgini at the Int. Conf. on Structure of the Nucleus at the Dawn of the Century, Bologna (Italy), May 29-June 3, 200

    Fragmentation cross sections of Fe^{26+}, Si^{14+} and C^{6+} ions of 0.3-10 A GeV on CR39, polyethylene and aluminum targets

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    New measurements of the total and partial fragmentation cross sections in the energy range 0.3-10 A GeV of Fe^{26+}, Si^{14+} and C^{6+} beams on polyethylene, CR39 and aluminum targets are presented. The exposures were made at Brookhaven National Laboratory (BNL), USA, and Heavy Ion Medical Accelerator in Chiba (HIMAC), Japan. The CR39 nuclear track detectors were used to identify the incident and survived beams and their fragments. The total fragmentation cross sections for all targets are almost energy independent while they depend on the target mass. The measured partial fragmentation cross sections are also discussed.Comment: 4 pages, 5 eps figures. Talk given at the 24th International Conference on Nuclear Tracks in Solids, Bologna, Italy, 1-5 September 200

    Nuclear Track Detectors for Environmental Studies and Radiation Monitoring

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    Several improvements were made for Nuclear Track Detectors (NTDs) used for environmental studies and for particle searches. A new method was used to determine the bulk etch rate of CR39 and Makrofol NTDs. It is based on the simultaneous measurement of the diameter and of the height of etch-pit cones caused by relativistic heavy ions (158 A GeV Pb(82+) and In(49+) ions) and their fragments. The use of alcohol in the etching solution improves the surface quality of NTDs and it raises their thresholds. The detectors were used for the determination of nuclear fragmentation cross sections of Iron and Silicon ions of 1.0 and 0.41 GeV/nucleon. These measurements are important for the determination of doses in hadron therapy and for doses received by astronauts. The detectors were also used in the search of massive particles in the cosmic radiation, for the determination of the mass spectrum of cosmic rays and for the evaluation of Po(210) alpha decay and of natural radon concentrations.Comment: 7 pages, 5 EPS figures. Presented at the 10th Topical Seminar on Innovative Particle and Radiation Detectors, 1-5 October 2006, Siena, Ital

    Search for strange quark matter and Q-balls with the SLIM experiment

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    We report on the search for Strange Quark Matter (SQM) and charged Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.) from 2001 to 2005. The SLIM experiment was a 427 m2^{2} array of Nuclear Track Detectors (NTDs) arranged in modules of 24×2424 \times 24 cm2^{2} area. SLIM NTDs were exposed to the cosmic radiation for 4.22 years after which they were brought back to the Bologna Laboratory where they were etched and analyzed. We estimate the properties and energy losses in matter of nuclearites (large SQM nuggets), strangelets (small charged SQM nuggets) and Q-balls; and discuss their detection with the SLIM experiment. The flux upper limits in the CR of such downgoing particles are at the level of 1.310151.3 10^{-15}/cm2^{2}/s/sr (90% CL).Comment: 4 pages, 7 eps figures. Talk given at the 24th International Conference on Nuclear Tracks in Solids, Bologna, Italy, 1-5 September 200

    Bulk Etch Rate Measurements and Calibrations of Plastic Nuclear Track Detectors

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    New calibrations of CR39 and Makrofol nuclear track detectors have been obtained using 158 A GeV Pb (82+) and In (49+) ions; a new method for the bulk etch rate determination, using both cone height and base diameter measurements was developed. The CR39 charge resolution based on the etch-pit base area measurement is adequate to identify nuclear fragments in the interval 7 <= Z/beta <= 49. For CR39 the detection threshold is at REL~50 MeV cm^2/g, corresponding to a nuclear fragment with Z/beta~7. Base cone area distributions for Makrofol foils exposed to Pb (82+) ions have shown for the first time all peaks due to nuclear fragments with Z > 50; the distribution of the etched cone heights shows well separated individual peaks for Z/beta = 78 - 83 (charge pickup). The Makrofol detection threshold is at REL 2700 MeV cm^2/g, corresponding to a nuclear fragment with Z/beta~50.Comment: 11 pages, 5 EPS figures. Submitted to Nucl. Instr. Meth.

    Search for magnetic monopoles at the Chacaltaya cosmic ray laboratory

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    The new large area (400 m2) experiment—SLIM—to search for magnetic monopoles and other exotic massive particles is presented. It uses of nuclear track detectors and is being deployed at the Chacaltaya cosmic ray laboratory for at least 4 years. The detection capability of the experiment is discussed

    Interdependence between the steel castings and manufacture of machines and equipment

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    Starting from the fact that the metallurgical industry is the main supplier of raw material both for the equipment and machines industry, as well as for the car industry, this paper analyses, by means of the regression function, to what extent the quantity of casting of steel was influenced, on the one hand by the manufacture of machines and equipment, and on the other hand, by the manufacture of car body. Data subject to the study were related to the period January 2002 – June 2016 (174 months) and was conducted both at the level of the European Union, as well as at the level of the main countries manufacturing steel at its level, namely: Germany, Italy, France and Spain

    Antibiotic resistance in community-acquired pneumonia. A romanian perspective

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    Community-acquired pneumonia (CAP) is one of the most common communicable diseases with a high mortality rate worldwide. Treatment is administered empirically based on clinical symptoms and the most commonly incriminated microorganisms in lower respiratory infections responsible for CAP. This study aimed to identify microorganisms responsible for CAP in patients hospitalized in an Emergency Hospital in Bucharest, Romania; to assess the impact of patients’ comorbidities and age on the survival level and to establish the degree of antimicrobial resistance of the most important isolated species. A total of 170 patients diagnosed with CAP from December 2017 through December 2018 were studied. Statistical analyses were performed considering the following data: survival rate, comorbidities, initiated pharmacotherapy, antibiogram results in case of refractory treatments. The overall survival rate was 36% among patients. Cardiovascular disease was incriminated as the highest risk factor. Concerning refractory antibiotic treatment, the microbiological results revealed that the most common bacterial strains detected were Klebsiella sp., Acinetobacter baumanii, S. aureus, E. coli and Pseudomonas, with high multiple antibiotic resistance (MAR) index. The results point out a real concern for patients with refractory CAP due to high antimicrobial resistance to the administered antibiotics in Romania. © 2020, Romanian Society for Pharmaceutical Sciences. All rights reserved
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