The KLOE electromagnetic calorimeter Adinolfi, M; Ambrosino, F; Antonelli, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2002, Letnik:
482, Številka:
1-2
Journal Article
Recenzirano
The KLOE detector was designed primarily for the study of CP violation in neutral kaon decays at DAΦNE, the Frascati φ-factory. The detector consists of a tracker and an electromagnetic calorimeter. ...A lead-scintillating-fiber sampling calorimeter satisfies best the requirements of the experiment, providing adequate energy resolution and superior timing accuracy. We describe in the following the construction of the calorimeter, its calibration and how the calorimeter information is used to obtain energy, point of entry and time of the arrival of photons, electrons and charged particles. With e+e− collision data at DAΦNE for an integrated luminosity of some 2pb−1 we find for electromagnetic showers, an energy resolution of 5.7%/E(GeV) and a time resolution of 54/E(GeV) ps. We also present a measurement of efficiency for low energy photons.
This paper investigates the productive value of crop biodiversity, with an application to a farming system in the Tigray region in the highlands of Ethiopia. We examine a general measure of the ...productive value of crop biodiversity and its components. Using Ethiopian farm-level data, agroecosystem productivity is investigated empirically. The analysis gives estimates of the value of diversity and its components. The value of crop biodiversity is estimated to be positive. The complementarity component is found to be large and statistically significant: it is the main source of crop biodiversity value in this agroecosystem of Ethiopia. However, the convexity component is negative, indicating that nonconvexity contributes to reducing the value of crop biodiversity.
The Mu2e experiment is constructing a calorimeter consisting of 1348 undoped cesium iodide (CsI) crystals in two disks. Each crystal has a dimension of 34 × 34 × 200 mm3 and is readout by a ...large-area silicon photomultipliers array. A series of technical specifications on mechanical and optical parameters was defined according to the calorimeter physics requirements. Preproduction CsI crystals were procured from three firms: Amcrys, Saint-Gobain, and Shanghai Institute of Ceramics. We report the quality assurance on crystal's scintillation properties and their radiation hardness against ionization dose and neutrons. With a fast decay time of about 30 ns and a light output of more than 100 p.e./MeV measured by a bialkali photomultiplier tube, undoped CsI crystals provide a cost-effective solution for Mu2e.
Mu2e will search for the Charge Lepton Flavor Violating (CLFV) conversion of a muon into an electron in the field of a nucleus. A clean discovery signature is provided by the mono-energetic ...conversion electron (
E
e
= 104.96 MeV). If no events are observed, Mu2e will set a limit on the ratio between the conversion and the nuclear capture rate below 3 × 10
−17
(at 90% C.L.). In order to confirm that the observed candidate is an electron, the calorimeter resolution requirements are to provide
E
res
< 10%,
T
res
< 500 ps for 100 MeV electrons while working in vacuum and in a high radiation environment and high magnetic field. The calorimeter is made of two annular aluminum disks, each one filled with 674 pure CsI crystals read out by SiPMs. A sophisticated mechanics and cooling system has been developed to support the crystals and cool the sensors. Radiation hard analog and fast digital electronics have been developed. In this paper the QC tests performed on the produced components and the construction status are reported, as well as the results obtained on the large size prototype with test beam data and at a cosmic ray test stand.
The adoption of certain farm management practices, such as tree planting and soil and water conservation, can reduce exposure to weather shocks. However, in many countries the adoption of such risk ...mitigating measures is far from complete. We explore how risk-sharing networks in the form of kinship, characterized by the moral imperative of within-group sharing, affects the adoption of risk mitigating activities in rural Ethiopia. We find suggestive evidence that compulsory sharing invites free riding and attenuates incentives for self-protection against weather shocks. We also find evidence of the existence of a possible substitution effect between credit and social networks.
This paper presents an empirical analysis of the impact of climate change on agriculture in a typical developing country. The economic implications of climate change are estimated by using both a ...farm productivity and a Ricardian framework. Data are drawn from about 1,000 farms producing cereal crops in the Nile Basin of Ethiopia. The thin plate spline method of spatial interpolation was used to predict household specific rainfall and temperature values using meteorological station data collected for 30 years across the regions. We found that climate change adaptation has a significant impact on both farm productivity and farm net revenues. We complement the analysis by providing an estimation of the determinants of adaptation. Extension services (both formal and farmer to farmer), as well as access to credit and information on future climate changes are key drivers of adaptation.
The tracking detector of the KLOE experiment Adinolfi, M; Ambrosino, F; Andryakov, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2002, Letnik:
488, Številka:
1
Journal Article
Recenzirano
The design and construction of the large Drift Chamber for the KLOE experiment at the Frascati φ-factory, DAΦNE, are described. The relevant aspects of the various elements of the detector are ...reviewed together with a description of the track reconstruction program and of the calibration procedures. The performance of the detector based on measurements with cosmic rays and with e
+e
− colliding beams during DAΦNE commissioning is presented.
The Mu2e experiment at Fermilab will search for the coherent \mu \rightarrow e conversion on aluminum atoms. The detector system consists of a straw tube tracker and a crystal calorimeter. A ...pre-production of 150 Silicon Photomultiplier arrays for the Mu2ecalorimeter has been procured. A detailed quality assurance has been carried out on each SiPM for the determination of its own operation voltage, gain, dark current and PDE. The measurement of the mean-time-to-failure for a small random sample of the pro-production group has been also completed as well as the determination of the dark current increase as a function of the ioninizing and non-ioninizing dose.
We explore whether traditional sharing norms in kinship networks affect consumption and accumulation decisions of poor black households in KwaZulu-Natal, South Africa. Using a proxy for the number of ...family dependents, our results are consistent with the interpretation that households try to evade their 'sharing obligations' by (i) accumulating durables that are non-sharable at the expense of durables that may be shared and (ii) reducing savings in liquid assets. By attenuating accumulation incentives, kinship sharing may come at the expense of income growth - if so, a culturally-induced poverty trap can possibly eventuate. We demonstrate tentative evidence that more extensive kinship networks are associated with lower incomes.
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