596 research outputs found
Monitoring of a therapeutic proton beam: preliminary tests of innovative thin silicon detectors.
Vascular injuries following road traffic collisions in a high-income developing country: a prospective cohort study
A Quantitative Approach to Estimate the Damage Inflicted by Traffic Pollution on Historic Buildings in Al-Salt City, Jordan
Traffic in the city of Al-Salt is not only putting pedestrians at risk and threatening the health of citizens, it is also damaging the town's historic buildings. Most stone buildings in the heritage-rich city are suffering adverse effects from vehicle-related pollution. This effect is highly visible soiling and discoloration from deposited carbon particles in the form of fine soot on most buildings. The level and progress of the damage depends on the geology of the stone and the proximity of the structure from traffic congestion. The accumulation of soot leads to the buildup of black sulfate (gypsum) skins on the limestone facade which causes the sound stone behind it to disintegrate. It is vital to the well-being of this historic treasure that the volume of the city traffic must be reduced and traffic flow improved. The main objective of this study is to qualitatively and quantitatively assess the damage caused to buildings of historical and cultural value by traffic pollution. Age of vehicles running on city’s streets and the rate of their emissions are quantified and analyzed. Several field investigations and laboratory tests were conducted to identify the chemical relations between pollutants and stone decay on these buildings. Keywords: Traffic pollution, tailpipe emission, vehicular emission, historic buildings, limeston
Tests of thin Low-Gain Avalanche Detectors for the characterization of therapeutic proton beams.
Preliminary test of innovative strip silicon detectors for therapeutic proton beam monitoring
Characterization of timing and spacial resolution of novel TI-LGAD structures before and after irradiation
The characterization of spacial and timing resolution of the novel Trench Isolated LGAD (TI-LGAD) technology is presented. This technology has been developed at FBK with the goal of achieving 4D pixels, where an accurate position resolution is combined in a single device with the precise timing determination for Minimum Ionizing Particles (MIPs). In the TI-LGAD technology, the pixelated LGAD pads are separated by physical trenches etched in the silicon. This technology can reduce the interpixel dead area, mitigating the fill factor problem. The TI-RD50 production studied in this work is the first one of pixelated TI-LGADs. The characterization was performed using a scanning TCT setup with an infrared laser and a Sr source setup
A new detector for the beam energy measurement in proton therapy: a feasibility study
Fast procedures for the beam quality assessment and for the monitoring of
beam energy modulations during the irradiation are among the most urgent
improvements in particle therapy. Indeed, the online measurement of the
particle beam energy could allow assessing the range of penetration during
treatments, encouraging the development of new dose delivery techniques for
moving targets. Towards this end, the proof of concept of a new device, able to
measure in a few seconds the energy of clinical proton beams (from 60 to 230
MeV) from the Time of Flight (ToF) of protons, is presented. The prototype
consists of two Ultra Fast Silicon Detector (UFSD) pads, featuring an active
thickness of 80 um and a sensitive area of 3 x 3 mm2, aligned along the beam
direction in a telescope configuration, connected to a broadband amplifier and
readout by a digitizer. Measurements were performed at the Centro Nazionale di
Adroterapia Oncologica (CNAO, Pavia, Italy), at five different clinical beam
energies and four distances between the sensors (from 7 to 97 cm) for each
energy. In order to derive the beam energy from the measured average ToF,
several systematic effects were considered, Monte Carlo simulations were
developed to validate the method and a global fit approach was adopted to
calibrate the system. The results were benchmarked against the energy values
obtained from the water equivalent depths provided by CNAO. Deviations of few
hundreds of keV have been achieved for all considered proton beam energies for
both 67 and 97 cm distances between the sensors and few seconds of irradiation
were necessary to collect the required statistics. These preliminary results
indicate that a telescope of UFSDs could achieve in a few seconds the accuracy
required for the clinical application and therefore encourage further
investigations towards the improvement and the optimization of the present
prototype
Thin low-gain avalanche detectors for particle therapy applications
none18The University of Torino (UniTO) and the National Institute for Nuclear Physics (INFN-TO) are investigating the use of Ultra Fast Silicon Detectors (UFSD) for beam monitoring in radiobiological experiments with therapeutic proton beams. The single particle identification approach of solid state detectors aims at increasing the sensitivity and reducing the response time of the conventional monitoring devices, based on gas detectors. Two prototype systems are being developed to count the number of beam particles and to measure the beam energy with time-of-flight (ToF) techniques. The clinically driven precision (< 1%) in the number of particles delivered and the uncertainty < 1 mm in the depth of penetration (range) in radiobiological experiments (up to 108 protons/s fluxes) are the goals to be pursued. The future translation into clinics would allow the implementation of faster and more accurate treatment modalities, nowadays prevented by the limits of state-of-the-art beam monitors. The experimental results performed with clinical proton beams at CNAO (Centro Nazionale di Adroterapia Oncologica, Pavia) and CPT (Centro di Protonterapia, Trento) showed a counting inefficiency <2% up to 100 MHz/cm2, and a deviation of few hundreds of keV of measured beam energies with respect to nominal ones. The progresses of the project are reported.noneVignati, A.; Donetti, M.; Fausti, F.; Ferrero, M.; Giordanengo, S.; Hammad Ali, O.; Mart Villarreal, O.A.; Mas Milian, F.; Mazza, G.; Monaco, V.; Sacchi, R.; Shakarami, Z.; Sola, V.; Staiano, A.; Tommasino, F.; Verroi, E.; Wheadon, R.; Cirio, R.Vignati, A.; Donetti, M.; Fausti, F.; Ferrero, M.; Giordanengo, S.; Hammad Ali, O.; Mart Villarreal, O. A.; Mas Milian, F.; Mazza, G.; Monaco, V.; Sacchi, R.; Shakarami, Z.; Sola, V.; Staiano, A.; Tommasino, F.; Verroi, E.; Wheadon, R.; Cirio, R
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