Nowadays, simple and non-destructive methods able to recognize pathogens in real time and in living tissues are still missing. This study has been designed to evaluate the presence of fungi (i.e. ...Gnomoniopsis spp.) in chestnuts. To this aim, a measurement setup based on terahertz radiation has been used to highlight the presence of fungal diseases in chestnut samples. A population of fifty chestnuts that was known to be partially infected by Gnomoniopsis spp., has been imaged in the low terahertz range by a compact and portable active imaging system equipped with a 100 GHz (0.1 THz) source. The relationship between the chestnut physical parameters, such as mass or volume, and the light attenuation in healthy and infected fruits has been tentatively explained by assuming a different water density and a different physical structure in healthy and unhealthy fruits, due to carbohydrates hydrolysis by the fungi. The preliminary results here described suggest that the sole analysis of the light attenuation combined with the measurement of weight or volume of a chestnut can provide an immediate indication of the presence of fungi in the fruits.
•Non-destructive imaging approaches able to recognize pathogens in real time in living tissue are still not available.•Fifty chestnuts, part of them infected by Gnomoniopsis spp., have been investigated using a THz spectroscopic approach.•Results suggest that our method can provide a fast confirmation of the presence of fungi in the chestnuts investigated.
Abstract
The SCT telescope has been proposed as a medium-sized telescope for the Cherenkov Telescope Array. One of the major upgrades is the design of the new Front End Electronics Module (FEEM). New ...FEEMs aim to read-out and digitize the SiPM pre-amplified signals down to the single photoelectron (phe). This phe signal is assumed equivalent to a signal with 2 mV peak amplitude and 500 MHz maximum bandwidth. FEEM should have a linear response up to 2 V for a required dynamic range of 1000 phe. FEEM noise equivalent of 0.5 phe - 1 mV of RMS noise - is an acceptable value. Due to the severe mechanical constraints, and to have a very compact electronics and low noise performance, FEEM consists of two stacked-up submodules, one dedicated to the power supplies and the other to house the FPGA, which reads out and sends digitized data to the main backplane. An FEEM is capable of digitizing 64 analog channels with a sampling frequency of 1 GSamples/s.
The development of terahertz based technology has given the opportunity for the realization of non destructive techniques capable of gaining meaningful information on delicate systems such as ...biological samples. Here, the health status of leaves in vivo has been monitored through a portable terahertz imaging system. The data have been extracted and analysed from the images acquired and compared with analogous results reported in the literature on similar systems. The possibilty of extracting additional information from the images regarding leaf details has also been explored.
Near UltraViolet High Density (NUV-HD) SiPMs produced by Fondazione Bruno Kessler in collaboration with INFN have been tested and characterized in INFN laboratories. The third generation of these ...devices (HD3) has proven to be suitable to equip the focal plane of the prototype Schwarzschild–Couder Medium Size Telescope (pSCT) proposed for the Cherenkov Telescope Array Observatory. Photosensors have been assembled in 4 16-pixel optical units coupled with TARGET–7 ASIC front-end electronics for amplification and digitization of the signal. At present, 9 modules have been successfully integrated on the pSCT camera and are currently taking data. In this contribution we report on the performances of the HD3 technology as single sensor and as assembled optical units, showing their performance and homogeneity in terms of gain and dark count rate.
Silicon Photomultipliers (SiPMs) are excellent devices to detect the faint and short Cherenkov light emitted in high energy atmospheric showers, and therefore suitable for use in imaging air ...Cherenkov Telescopes. The high density Near Ultraviolet Violet SiPMs (NUV-HD3) produced by Fondazione Bruno Kessler (FBK) in collaboration with INFN were used to equip optical modules for a possible upgrade of the Schwarzschild-Couder Telescope camera prototype, in the framework of the Cherenkov Telescope Array project. SiPMs are 6×6 mm
2
devices based on 40×40 μm
2
microcells optimized for photo-detection at the NUV wavelengths. More than 40 optical modules, each composed by a 4×4 array of SiPMs, were assembled. In this contribution we report on the development and on the assembly of the optical modules, their validation and integration in the camera.
The authors describe a VLSI processor for pattern recognition based on content addressable memory (CAM) architecture, optimized for on-line track finding in high-energy physics experiments. A large ...CAM bank stores all trajectories of interest and extracts the ones compatible with a given event. This task is naturally parallelized by a CAM architecture able to output identified trajectories, searching for matches on 96-bit wide patterns, in just a few 40-MHz clock cycles. We have developed this device (called the AMchip03 processor) for the silicon vertex trigger (SVT) upgrade at the Collider Detector experiment at Fermilab (CDF) using a standard-cell VLSI design methodology. This approach provides excellent pattern density, while sparing many of the complexities and risks associated to a full-custom design. The cost/performance ratio is better by well more than one order of magnitude than an FPGA-based design. This processor has a flexible and easily configurable structure that makes it suitable for applications in other experimental environments. They look forward to sharing this technology
MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a series of upgrades, involving the ...exchange of the MAGIC-I camera and its trigger system, as well as the upgrade of the readout system of both telescopes. We use observations of the Crab Nebula taken at low and medium zenith angles to assess the key performance parameters of the MAGIC stereo system. For low zenith angle observations, the standard trigger threshold of the MAGIC telescopes is ∼ 50GeV. The integral sensitivity for point-like sources with Crab Nebula-like spectrum above 220GeV is (0.66 ± 0.03)% of Crab Nebula flux in 50h of observations. The angular resolution, defined as the σ of a 2-dimensional Gaussian distribution, at those energies is ≲ 0.07°, while the energy resolution is 16%. We also re-evaluate the effect of the systematic uncertainty on the data taken with the MAGIC telescopes after the upgrade. We estimate that the systematic uncertainties can be divided in the following components: < 15% in energy scale, 11%–18% in flux normalization and ± 0.15 for the energy spectrum power-law slope.
The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. The telescopes are designed to measure Cherenkov light from air showers ...initiated by gamma rays in the energy regime from around 50GeV to more than 50TeV. The two telescopes were built in 2004 and 2009, respectively, with different cameras, triggers and readout systems. In the years 2011–2012 the MAGIC collaboration undertook a major upgrade to make the stereoscopic system uniform, improving its overall performance and easing its maintenance. In particular, the camera, the receivers and the trigger of the first telescope were replaced and the readout of the two telescopes was upgraded. This paper (Part I) describes the details of the upgrade as well as the basic performance parameters of MAGIC such as raw data treatment, linearity in the electronic chain and sources of noise. In Part II, we describe the physics performance of the upgraded system.
One of the proposed Medium-Sized Telescopes for the Cherenkov Telescope Array is the dual mirror optics Schwarzschild–Couder Telescope (SCT). The prototype SCT camera is currently equipped with 24 ...SiPM modules each one made of 64 pixels. The upgrade of the current camera is in progress, with the aim of fully equipping the 177 SiPM modules. A new front-end electronics is being developed and tested in order to improve the noise performance and match CTA requirements. In this process, 11328 SiPMs and the related electronics will be tested in the laboratories before the assembly on the telescope camera. The SiPM Multichannel ASIC for high Resolutions Cherenkov Telescope (SMART) has been developed by INFN to amplify the SiPM signals to be digitized and inserted in the trigger logic based on the TeV Array with GSa/s sampling and Experimental Trigger Application Specific Integrated Circuit (TARGET ASICs). An experimental setup has been devised to test about 750 SMART, which will be used to equip the full camera of the prototype SCT. Each SMART was tested for proper operation in response to a laser pulse. In this contribution we present a detailed scheme of the test bench and the first results obtained on the quality control measurements.
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