The ALICE Zero Degree Calorimeters (ZDC) provide information about event geometry in heavy-ion collisions through the detection of spectator nucleons and allow to estimate the delivered luminosity. ...They are also very useful in p–A collisions, allowing an unbiased estimation of collision centrality. The Run 3 operating conditions will involve a tenfold increase in instantaneous luminosity in heavy-ion collisions, with event rates that, taking into account the different processes, could reach 5 MHz in the ZDCs. The challenges posed by this demanding environment lead to a redesign of the readout system and to the transition to a continuous acquisition. The new system is based on 12 bit, 1 Gsps FMC digitizers that will continuously sample the 26 ZDC channels. Triggering, pedestal estimation and luminosity measurements will be performed on FPGA directly connected to the front-end. The new readout system and the performances foreseen in Run 3 are presented.
The most promising probe to establish the Majorana or Dirac nature of the neutrino is the neutrinoless double beta decay and the effective neutrino mass would be evaluated by the knowledge of the ...corresponding nuclear matrix elements. Also measurements of the Double Charge Exchange (DCE) interactions of heavy ion beams can get information on them. The NUMEN experiment based on the pre-existing large acceptance MAGNEX spectrometer and integrated with new challenging components aims at measuring DCE cross sections using ion beams of unprecedented intensity (10
13
pps) on specific isotopes at INFN-LNS in Catania. Expected rate on the sensitive area of about 0.15 m
2
reaches up to about 5 Mpps, demanding for adequate detectors in measuring position, direction, energy, mass and charge of the ions produced by interactions. Gamma detectors surround a scattering chamber containing the target.
•The RFQ linac and its RF power system were installed to the LIPAc facility.•The eight RF chains provide the balanced RF power to the single RFQ cavity in-phase using a feedback loop and a ...synchronization system.•The peak power in the cavity achieved 150 kW in the pulse mode, which corresponds approximately to the required electric field to accelerate proton beam.
The Radio Frequency Quadrupole (RFQ) linac and 1.6 MW RF power system of the Linear IFMIF Prototype Accelerator (LIPAc) facility in the International Fusion Energy Research Center (IFERC) in Rokkasho (Japan) has been installed and conditioned. During the assembly and tuning process, the RFQ cavity was protected with a temporary tent from the potential deterioration of performance caused by dust. The vacuum in the cavity was improved through the 100 °C baking process of the cavity. The high power test of the 175 MHz RF systems up to 200 kW in CW for each of the eight RF chains was performed for checking its stable output reproducibility in Japan, before connecting 9–3/16 inch coaxial transmission lines from the RF chains to the RF input couplers of the cavity. It was confirmed that the eight RF chains provided the balanced RF power to the single RFQ cavity in-phase using a feedback loop and a synchronization system. The peak power in the cavity achieved 150 kW in the pulsed mode, which corresponds approximately to the required electric field to accelerate proton beam. Such RF conditioning process is ongoing to achieve 600 kW approximately required for deuteron beam commissioning planned in 2018.
Osteoradionecrosis (ORN) of the mandible is a major complication of radiation therapy of head and neck cancer with a potential of occurrence ranging from 5 to 15% of the irradiated patients. Due to ...the gradual necrotic process, the mandibular bone becomes necrotic and looses its spontaneous regeneration ability. Containing an elevated content of mitogenic and osteogenic growth factors, the use of platelet rich plasma (PRP) from autologous source has been suggested to re-activate the healing process of osteogenesis. Autologous PRP gel was introduced into the ORN necrotic defect of a 44-year old patient previously treated for squamous cell carcinoma of the tongue, subsequent to proper surgical debridement. We report post-operative two-year follow-up demonstrated by panoramic X-ray which showed regain of the mandibular bone continuity with a complete repair of the necrotic defects. We conclude that this case illustrates an incident of successful regeneration of ORN critical-sized defect of the mandible by autologous PRP gel.
The zero degree calorimeters for the ALICE experiment Puddu, G.; Arnaldi, R.; Chiavassa, E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2007, Letnik:
581, Številka:
1
Journal Article
Recenzirano
The Zero Degree Calorimeters (ZDC) for the ALICE experiment will measure the energy of the spectator nucleons in heavy ion collisions at the CERN LHC, providing a direct measure of the centrality of ...the collisions. ZDC are spaghetti calorimeters, which detect the Cherenkov light produced by the shower particles in silica optical fibers embedded in a dense absorber. The main characteristics of the ZP and ZN detectors are described in this article. The calorimeters were tested at the CERN SPS using pion and electron beams with momenta ranging from 50 to
200
GeV
/
c
. Test beam results such as the calorimeter response, the energy resolution, the signal uniformity and the localizing capability are presented.
Due to be launched in late 2021, the Imaging X-ray Polarimetry Explorer (IXPE) is a NASA Small Explorer mission designed to perform polarization measurements in the 2–8 keV band, complemented with ...imaging, spectroscopy and timing capabilities. At the heart of the focal plane is a set of three polarization-sensitive Gas Pixel Detectors (GPD), each based on a custom ASIC acting as a charge-collecting anode.
In this paper we shall review the design, manufacturing, and test of the IXPE focal-plane detectors, with particular emphasis on the connection between the science drivers, the performance metrics and the operational aspects. We shall present a thorough characterization of the GPDs in terms of effective noise, trigger efficiency, dead time, uniformity of response, and spectral and polarimetric performance. In addition, we shall discuss in detail a number of instrumental effects that are relevant for high-level science analysis—particularly as far as the response to unpolarized radiation and the stability in time are concerned.
Results of the Italian neu_ART project Re, A; Albertin, F; Bortolin, C ...
IOP conference series. Materials Science and Engineering,
01/2012, Letnik:
37, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The neu_ART project aims at developing state of the art transmission imaging and computed tomography techniques, applied to art objects, by using neutrons as well as more conventional X-rays. In this ...paper a facility for digital X-ray radiography of large area paintings on canvas or wooden panels and for the X-ray tomography of large size wooden artifacts, recently installed in a protected area, is presented. The results of a K-edge radiography facility that will soon be installed in the same area are also shown.
The Neutron Zero Degree Calorimeter for the ALICE experiment Arnaldi, R.; Chiavassa, E.; Cicalò, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2006, Letnik:
564, Številka:
1
Journal Article
Recenzirano
In this paper, we present the performance of the Neutron Zero Degree Calorimeter (ZN) for the ALICE experiment. The ZN is a quartz-fiber spaghetti calorimeter, which will measure the energy of the ...spectator neutrons in heavy ion collisions at the CERN LHC. Its principle of operation is based on the detection of the Cherenkov light produced by the charged particles of the shower in silica optical fibers, embedded in a W-alloy absorber. The detector was tested at CERN SPS using positive hadron and positron beams with momenta ranging from 50 to
150
GeV
/
c
. The response of the calorimeter, the energy resolution, the localizing capability, the signal uniformity and the transverse profile of the detectable hadronic shower are presented.
The zero degree calorimeters (ZDCs) for the ALICE experiment will measure the energy of the spectator nucleons in heavy ion collisions at the CERN LHC. The dipole magnets of the LHC beam optics will ...separate the ion beams from the spectator protons; the spectator protons and neutrons will be respectively detected by the proton (ZP) and the neutron (ZN) calorimeters. Since all the spectator nucleons have the same energy, the calorimeter response is proportional to their number, providing a direct information on the centrality of the collision. ZDCs are spaghetti calorimeters, which detect the Cherenkov light produced by the shower particles in silica optical fibers embedded in a dense absorber. The technical characteristics of ZP and ZN detectors are described. The calorimeters have been tested at the CERN SPS using pion and electron beams with momenta ranging from 50 to 200 GeV/c; the ZN detector behaviour has also been studied with an indium beam of 158 GeV/c per nucleon. The beam test results are presented: the calorimeters response, the energy resolution and the localizing capability. Also the signal uniformity and a comparison between the transverse profile of the hadronic and electromagnetic shower are discussed. Moreover the differences between the ZP detector responses to protons and pions of the same energy have been investigated, exploiting the proton contamination in the positive pion beams.
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