532 research outputs found
The NESSiE concept for sterile neutrinos
The NESSiE (Neutrino Experiment with SpectrometerS in Europe) experimental proposal is a project to combine two liquid argon (LAr) image detectors (Time Projection Chambers, TPC) and two magnetic spectrometers; for the
observation of electron and muon neutrino events at different distances. At the near (400 m) and far (1600 m) positions from the neutrino beam origin. The experiment
aims to definitively clarify the present neutrino oscillation scenarios and to explore (or to refute) the possibility of the existence of sterile neutrinos. The main characteristics of the spectrometers are described here. Spectrometers will employ a bipolar magnetic field with iron slabs, and a new concept air-core magnet, to perform
charge identification and muon momentum measurements in the energy range from ∼ 100MeV to few GeV over a large transverse area (> 50m2). The performances of the spectrometers as stand-alone detectors are summarized in terms the νμ disappearance sensitivity plot for an exposure of two years with ¯νμ plus one year with νμ
Natural Gas and Inequality in Bolivia after Nationalization
The high oil prices and the sharp increases in royalties mean that the natural gas boom in Bolivia has become very important for the economy. This paper uses a Computable General Equilibrium (CGE) model to assess the impacts of this boom on key macroeconomic variables as well as the distribution of incomes in the society. From a macroeconomic perspective, the natural gas boom is a blessing, adding around 1 percentage point to GDP growth rates for at least a decade, and sharply increasing government revenues available for public spending and investment. However, the poorest segments of the population (rural small-holders and urban informals) suffer actual reductions in their real incomes, compared to the counterfactual scenario without the gas boom. This means that the natural gas boom not only causes an increase in inequality but also an increase in poverty. The paper finishes with some policy recommendations on how to counteract the negative side effects of the natural gas boom.Natural Gas, Inequality, CGE model, Bolivia
Status of the GERDA experiment
The GERDA experiment is designed to search for neutrinoless double beta decay (0νββ) using76Ge, therefore asses the nature of neutrinos (Dirac or Majorana). In the so-called Phase I, with an exposure of 21.6kr yr, GERDA reached a background index (BI) of 10−2 cts/(keV kg yr) at 90% CL No signal was found during this phase and a lower limit on the process half-life of 2.1 × 1025 yr was derived (90% CL). GERDA is currently being upgraded to its Phase II, where the 76Ge mass will be double, and it is expected to reduce by an order of magnitude the BI. For 0νββ half-lives at the order of 1026 yr will be derived in the absence of signal. The experimental techniques used by GERDA will be depicted and the most relevant results from Phase I will be shown; as well as details on the upgrades of Phase II, including the status of the additional detectors deployed recently, and the new background reduction techniques using the active liquid Argon veto
Gas Natural y Desigualdad en Bolivia Después de la Nacionalización
Los precios altos del petróleo y el significativo incremento de los ingresos públicos provenientes de su explotación han implicado que el gas natural se vuelva muy importante para la economía boliviana. Este trabajo utiliza un modelo de Equilibrio General Computarizado (EGC) para evaluar los impactos de este boom sobre las variables macroeconómicas claves así como respecto de la distribución de ingresos en la sociedad. Desde una perspectiva macroeconómica, el boom del gas natural parece ser una bendición, pues podría elevar en cerca de un punto porcentual las tasas de crecimiento del PIB durante por lo menos una década, incrementando vigorosamente los ingresos del gobierno para realizar gastos e inversiones públicas. Sin embargo, los segmentos más pobres de la población (pequeños agricultores e informales urbanos) podrían verse seriamente afectados, sufriendo reducciones en sus ingresos reales en comparación con el escenario opuesto, es decir, sin el boom del gas. Esto quiere decir que el boom del gas natural no sólo podría causar un aumento en la desigualdad sino también una expansión de la pobreza. Este trabajo termina con algunas recomendaciones en cuanto a políticas que sugieren cómo contrarestar los efectos secundarios negativos del boom de gas natural.Gas Natural, Desigualdad, modelo EGC, Bolivia
Fragmentation studies of high energy ions using CR39 nuclear track detectors
We report on the measurements of the total charge changing fragmentation
cross sections in high-energy nucleus-nucleus collisions using Fe, Si and Pb
incident ions. Several stacks of CR39 nuclear track detectors with different
target combinations were exposed at normal incidence to high energy accelerator
beams to integrated densities of about 2000 ions/cm^2. The nuclear track
detector foils were chemically etched, and ion tracks were measured using an
automatic image analyzer system. The cross section determination is based on
the charge identification of beam ions and their fragments and on the
reconstruction of their path through the stacks.Comment: 5 pages, 4 EPS figures. Corrected Eq. 3 and Table 1. Presented at the
10th Inter. Symp. Radiat. Phys., Coimbra, Portugal, 17-22 Sept. 200
Cosmic ray abundance measurements with the CAKE balloon experiment
We present the results from the CAKE (Cosmic Abundance below Knee Energy)
balloon experiment which uses nuclear track detectors. The final experiment
goal is the determination of the charge spectrum of CR nuclei with Z > 30 in
the primary cosmic radiation. The detector, which has a geometric acceptance of
\~ 1.7 m2 sr, was exposed in a trans-mediterranean stratospheric balloon
flight. Calibrations of the detectors used (CR39 and Lexan), scanning
strategies and algorithms for tracking particles in an automatic mode are
presented. The present status of the results is discussedComment: 5 pages, 3 figures, proceeding to 29 ICRC, 2005, Pune Indi
Fragmentation cross sections of Fe^{26+}, Si^{14+} and C^{6+} ions of 0.3-10 A GeV on CR39, polyethylene and aluminum targets
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
Net carbon emissions from deforestation in Bolivia during 1990-2000 and 2000-2010: results from a carbon bookkeeping model
Accurate estimates of global carbon emissions are critical for understanding global warming. This paper estimates net carbon emissions from land use change in Bolivia during the periods 1990-2000 and 2000-2010 using a model that takes into account deforestation, forest degradation, forest regrowth, gradual carbon decomposition and accumulation, as well as heterogeneity in both above ground and below ground carbon contents at the 10 by 10 km grid level. The approach permits detailed maps of net emissions by region and type of land cover. We estimate that net CO2 emissions from land use change in Bolivia increased from about 65 million tons per year during 1990-2000 to about 93 million tons per year during 2000-2010, while CO2 emissions per capita and per unit of GDP have remained fairly stable over the sample period. If we allow for estimated biomass to increase in mature forests, net CO2 emissions drop to close to zero. Finally, we find these results are robust to alternative methods of calculating emissions
Search for Intermediate Mass Magnetic Monopoles and Nuclearites with the SLIM experiment
SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic
ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It
is devoted to the search for intermediate mass magnetic monopoles (107-1013
GeV/c2) and nuclearites in the cosmic radiation using stacks of CR39 and
Makrofol nuclear track detectors. In four years of operation it will reach a
sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of
the calibration of CR39 and Makrofol and the analysis of a first sample of the
exposed detector.Comment: Presented at the 22nd ICNTS, Barcelona 200
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