This paper discusses the hadronic energy reconstruction of two combined electromagnetic and hadronic calorimeter systems using physics prototypes of the CALICE collaboration: the silicon-tungsten ...electromagnetic calorimeter (Si-W ECAL) and the scintillator-SiPM based analog hadron calorimeter (AHCAL); and the scintillator-tungsten electromagnetic calorimeter (ScECAL) and the AHCAL. These systems were operated in hadron beams at CERN and FNAL, permitting the study of the performance in combined ECAL and HCAL systems. Two techniques for the energy reconstruction are used, a standard reconstruction based on calibrated sub-detector energy sums, and one based on a software compensation algorithm making use of the local energy density information provided by the high granularity of the detectors. The software compensation-based algorithm improves the hadronic energy resolution by up to 30% compared to the standard reconstruction. The combined system data show comparable energy resolutions to the one achieved for data with showers starting only in the AHCAL and therefore demonstrate the success of the inter-calibration of the different sub-systems, despite of their different geometries and different readout technologies.
A highly granular electromagnetic calorimeter with scintillator strip readout is being developed for future linear collider experiments. A prototype of 21.5 X0 depth and 180×180mm2 transverse ...dimensions was constructed, consisting of 2160 individually read out 10×45×3mm3 scintillator strips. This prototype was tested using electrons of 2–32 GeV at the Fermilab Test Beam Facility in 2009. Deviations from linear energy response were less than 1.1%, and the intrinsic energy resolution was determined to be (12.5±0.1(stat.)±0.4(syst.))%∕EGeV⊕(1.2±0.1(stat.)−0.7+0.6(syst.))%, where the uncertainties correspond to statistical and systematic sources, respectively.
A detailed investigation of hadronic interactions is performed using π−-mesons with energies in the range 2–10 GeV incident on a high granularity silicon–tungsten electromagnetic calorimeter. The ...data were recorded at FNAL in 2008. The region in which the π−-mesons interact with the detector material and the produced secondary particles are characterised using a novel track-finding algorithm that reconstructs tracks within hadronic showers in a calorimeter in the absence of a magnetic field. The principle of carrying out detector monitoring and calibration using secondary tracks is also demonstrated.
We present a study of the response of the highly granular Digital Hadronic Calorimeter with steel absorbers, the Fe-DHCAL, to positrons, muons, and pions with momenta ranging from 2 to 60GeV/c. ...Developed in the context of the CALICE collaboration, this hadron calorimeter utilises Resistive Plate Chambers as active media, interspersed with steel absorber plates. With a transverse granularity of 1×1cm2 and a longitudinal segmentation of 38 layers, the calorimeter counted 350,208 readout channels, each read out with single-bit resolution (digital readout). The data were recorded in the Fermilab test beam in 2010–11. The analysis includes measurements of the calorimeter response and the energy resolution to positrons and muons, as well as detailed studies of various shower shape quantities. The results are compared to simulations based on Geant4, which utilise different electromagnetic and hadronic physics lists.
•Periodicity of shoot and root growth affects the trunk diameter variation (TDV).•Fruit load played a dominant role in determining the TDV.•TDV analyses may provide an integrative “holistic view” of ...the tree.•Maximum daily shrinkage cannot be used on an absolute basis for irrigation control.
The objective was to investigate the combined effect of irrigation regime and fruit load on trunk-diameter variation patterns of ‘Hass’ avocado trees grown in lysimeters, at different phenological periods. Plant water uptake of both fruited and defruited trees was monitored at high temporal resolution during successive growth stages. The trunk growth rate (TGR) during all the experiments was not affected by the irrigation treatments, yet daily TGR fluctuated significantly during the season, probably in association with periodic changes in the priority of partitioning of carbohydrates between reproductive and vegetative plant organs, i.e., flushes of shoot or root growth. Fruit load clearly played a dominant role in determining TGR, very likely because of the dramatic effect of fruit load on stomatal conductance and leaf carbohydrate concentration and, therefore, on the overall availability of assimilates. Thus, analyses of trunk diameter variation (TDV) data that lead to evaluation of TGR and maximum trunk diameter variation (MTDV) reflect phenological stages and periodicity of shoot, fruit and root growth, and also may provide an integrative, “holistic viewpoint” of overall tree status.
The observed high dependency between the MTDV and irrigation treatments may indicate that MTDV actually depends on water-stress history rather than on the actual plant-water status. Thus, MTDV cannot be used on an absolute basis for irrigation management control. On the other hand, it may be a very efficient aid to control irrigation when used on a relative basis, after identifying the impacts of local phenological and environmental factors on the MTDV. Furthermore, the immediate MTDV response to accidental faults may illustrate the advantages of using dendrometer devices for remotely controlling irrigation systems.
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•Metallic top layer did not prevent the photoaging of the polymer matrix.•Photoaging caused the alteration of the silver top layer with the formation of defects.•Loss of the ...thermo-optical properties of the composite material due to the alteration of the metallic surface.
In this paper, we have sought to determine if a reflective silver coating layer could prevent the degradation of a silver/acrylate polymer assembly and the loss of its optical property in an environment simulating sunlight. For this purpose, a multiscale approach from micro(nano) scale to macroscopic scale was applied. The overcomes of this investigation revealed that the metallic coating did not act as a barrier against photooxidation of the polymer matrix and silver nanoparticles, on contrary, catalysed the degradation process. The multiscale approach showed that not only the matrix underwent structural and architectural changes with the formation of oxidative products and volatile compounds due to chain scission reaction, but also the alteration of the metallic layer with the formation of defects at its surface, evidenced by optical and atomic force microscopy.
An original approach using photo-DSC allowed to monitor the thermo-optical properties of the material. It pointed out the loss of the optical properties of the silver/polymer assembly during irradiation that was linked to the degradation of the acrylate polymer.
This paper presents results obtained with the combined CALICE Scintillator Electromagnetic Calorimeter, Analogue Hadronic Calorimeter and Tail Catcher & Muon Tracker, three high granularity ...scintillator-silicon photomultiplier calorimeter prototypes. The response of the system to pions with momenta between 4 GeV/c and 32 GeV/c is analysed, including the average energy response, resolution, and longitudinal shower profiles. Two techniques are applied to reconstruct the initial particle energy from the measured energy depositions; a standard energy reconstruction which is linear in the measured depositions and a software compensation technique based on reweighting individually measured depositions according to their hit energy. The results are compared to predictions of the GEANT 4 physics lists QGSP_BERT_HP and FTFP_BERT_HP.
The high granularity of the CALICE Semi-Digital Hadronic CALorimeter (SDHCAL) provides the capability to reveal the track segments present in hadronic showers. These segments are then used as a tool ...to probe the behaviour of the active layers in situ, to better reconstruct the energy of these hadronic showers and also to distinguish them from electromagnetic ones. In addition, the comparison of these track segments in data and the simulation helps to discriminate among the different shower models used in the simulation. To extract the track segments in the showers recorded in the SDHCAL, a Hough Transform is used after being adapted to the presence of the dense core of the hadronic showers and the SDHCAL active medium structure.
Turgor pressure provides a sensitive indicator for irrigation scheduling. Leaf turgor pressure of Musa acuminate was measured by using the so-called leaf patch clamp pressure probe, i.e. by ...application of an external, magnetically generated and constantly retained clamp pressure to a leaf patch and determination of the attenuated output pressure P(p) that is highly correlated with the turgor pressure. Real-time recording of P(p) values was made using wireless telemetric transmitters, which send the data to a receiver base station where data are logged and transferred to a GPRS modem linked to an Internet server. Probes functioned over several months under field and laboratory conditions without damage to the leaf patch. Measurements showed that the magnetic-based probe could monitor very sensitively changes in turgor pressure induced by changes in microclimate (temperature, relative humidity, irradiation and wind) and irrigation. Irrigation effects could clearly be distinguished from environmental effects. Interestingly, oscillations in stomatal aperture, which occurred frequently below turgor pressures of 100 kPa towards noon at high transpiration or at high wind speed, were reflected in the P(p) values. The period of pressure oscillations was comparable with the period of oscillations in transpiration and photosynthesis. Multiple probe readings on individual leaves and/or on several leaves over the entire height of the plants further emphasised the great impact of this non-invasive turgor pressure sensor system for elucidating the dynamics of short- and long-distance water transport in higher plants.
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