The Mu2e calorimeter consists of 1348 pure CsI crystals coupled to two large area UV-extended Silicon Photomultipliers (SiPMs) organized in two separate annular disks. An intense R&D phase has been ...pursued to check if this configuration satisfies the Mu2e requirements. In May 2017, a dedicated test has been performed at the Beam Test Facility (BTF) in Frascati (Italy) where the large calorimeter prototype (Module-0) has been exposed to an electron beam in the energy range between 60 and 120 MeV. The prototype consists of 51 crystals, each one readout by two Mu2e SiPMs. We present results for timing and energy resolution both for electrons at normal incidence (0°) and at a grazing impact angle (50°) more similar to the experiment configuration. At 100 MeV, an energy resolution of 5.4% (7.4%) at normal (grazing) incidence has been achieved in good agreement with Monte Carlo expectation. In the same energy range, a time resolution of ∼ XX ps (∼ YY ps) has been measured at normal incidence with 1 GHz (250 MHz) sampling rate. Dependence of time and energy resolutions as a function of beam energy and impinging angle are also presented.
Design and status of the Mu2e Calorimeter Atanov, N.; Baranov, V.; Budagov, J. ...
2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC),
2017-Oct.
Conference Proceeding
The Mu2e calorimeter is composed by \sim 1400 un- doped CsI crystals coupled to large area UV extended Silicon Photomultipliers(SIPMs) arranged intwo annular disks. This calorimeter has to provide ...precise information on energy, timing and position resolution. It should also be fast enough towithstand the high rate background and it mustoperate and survive in a high radiation environment. All steps done for the construction and test of the Module -0 prototype, that is an array of51 pre-production crystals, are reported. The Module -0 was exposed to an electron beam in the energy range around 100 MeV at the BTF (Beam Test Facility) inFrascati. Preliminary results of timing and energy resolution at normal incidence are shown.
The Mu2e calorimeter consists of 1348 undoped CsI crystals coupled to two large area UV-extended Silicon Photomultipliers (SiPMs). A modular and custom SiPM layout, a 3×2 matrix of 6×6 mm2 monolithic ...SiPMs, has been developed to satisfy the Mu2e requirements. As well as ensuring the performances needed for the muon-to-electron conversion search, these photosensors have to guarantee a good reliability while operating maintenance-free in the Mu2e hostile environment: any failure can only be replaced during a long technical shut-down scheduled once a year. After testing prototypes from different vendors, we selected Hamamatsu and the final production of about 4000 pieces is now ongoing. A detailed Quality Assurance (QA) program is then mandatory to minimize the risk of an unexpected further degradation in the performances. The QA process for each photosensor includes a first visual inspection and the subsequent characterization of each of its monolithic cells by means of an automatized test station, able to measure the breakdown voltage, the gain and the dark current. For each production batch (∼300 pieces), 5 devices are exposed to a neutron fluency up to ∼1.4×1011 1 MeV (Si) eq. n/cm2; others 15 devices are undergone an accelerated aging in order to verify the Mean Time To Failure (MTTF) of the batch. A summary of the QA and the results for the firsts 4 production batches are presented in the paper.
The Alpha Magnetic Spectrometer (AMS) is a precision particle physics detector on the International Space Station (ISS) conducting a unique, long-duration mission of fundamental physics research in ...space. The physics objectives include the precise studies of the origin of dark matter, antimatter, and cosmic rays as well as the exploration of new phenomena. Following a 16-year period of construction and testing, and a precursor flight on the Space Shuttle, AMS was installed on the ISS on May 19, 2011. In this report we present results based on 120 billion charged cosmic ray events up to multi-TeV energies. This includes the fluxes of positrons, electrons, antiprotons, protons, and nuclei. These results provide unexpected information, which cannot be explained by the current theoretical models. The accuracy and characteristics of the data, simultaneously from many different types of cosmic rays, provide unique input to the understanding of origins, acceleration, and propagation of cosmic rays.
Commonage represents land held under common property that incorporates a system of local cooperative arrangements and rules to conserve and manage the Irish uplands. We analyze the institutional and ...economic factors that influence the behavior of commonage farmers under a common property regime using a recursive bivariate probit model. Results show that (1) cooperation has a positive and important impact on commonage conservation; (2) agricultural policies by way of livestock premia increase the level of degradation; while (3) farm financial support through agri-environment measures positively affects commonage conservation and encourages cooperation between farmers. (JEL Q24, Q15)
In this paper we investigate how consumers respond to the UK nutritional food label Traffic Light System (TLS). Employing a choice experiment (CE) we find that consumers appear to behave in a manner ...consistent with our expectations regarding the impact of the TLS. We identify a strong preference on the part of respondents to avoid a basket of goods containing a mix of foods with any “Red” lights. In addition, we find that consumers have a hierarchy of importance in terms of perception of the various nutrients examined and there are clear behavioural differences associated with particular socio-economic characteristics confirming early research on the use of nutrition labels. Overall our results indicate significant heterogeneity in the attitudes and responses of consumers to the TLS nutritional food labels within and across socio-economic strata.
We propose a novel laboratory experiment to document the pressure to share income within social networks in Africa. We find that the redistributive pressure exerted via the possibility of receiving a ...claim increases altruism, while the possibility of hiding from such claim reduces it. Our results indicate that sharing norms are crucial drivers of giving to other members of the network. We also find that pressure to share has a detrimental effect on the undertaking of profitable but risky investments.
This article investigates the relationship between insecure property rights and land disputes using farm household panel data from the highlands of Ethiopia. Our identification strategy relies on the ...gradual rollout of a land certification program. We find that tenure security significantly reduces the likelihood for a farm household to experience land disputes. We further document that water scarcity during the rainy seasons is an important determinant of land disputes. However, farm households that have been certified are significantly less likely to experience land disputes triggered by water scarcity than farm households without land certification.
This paper uses a farm level panel data from Ethiopia and a comprehensive empirical strategy to investigate the contribution of crop biodiversity on food production. We find that increasing the ...number of crop variety increases production. This result is stronger when rainfall level is lower. Moreover, the productivity analysis is complemented with the study of the determinants of farm level crop biodiversity. Empirical results suggest that rainfall, tenure security and household endowments tend to govern crop diversity decisions at the farm level.
•This paper uses exogenous variation during the growing season to identify the role of income on discounting in the Highlands of Ethiopia.•We take advantage of the availability of panel data to ...control for individual specific sources of heterogeneity.•We find that income variations driven by anomalies in rainfall are strong predictors of farmers’ subjective discount rates.•We estimate that a 10% increase in negative rainfall anomalies, increases subjective discount rates by 20%.•Discounting is significantly correlated with the likelihood of undertaking agricultural investments.
We have combined farm household panel data, weather data and discount rates, as measured by a hypothetical survey question, to estimate the impact of income on discounting. This paper has found that income variation driven by anomalies in rainfall during the main growing season is a strong predictor of farmers’ subjective discount rates. Farmers prefer a smaller immediate reward to a larger deferred one when affected by negative income shocks, while they display lower discount rates when the income shocks are positive. We have also found that higher discount rates are negatively correlated with profitable agricultural investments.
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