An upgrade of the Near Detector of the T2K long baseline neutrino oscillation experiment, ND280, has been proposed. This upgrade will include two new Time Projection Chambers, each equipped with 16 ...resistive Micromegas modules for gas amplification. A first prototype of resistive Micromegas has been designed, built, installed in the HARP field cage, and exposed to a beam of charged particles at CERN. The data have been used to characterize the performances of the resistive Micromegas module. A spatial resolution of 300 μm and a deposited energy resolution of 9% were observed for horizontal electrons crossing the TPCs at 30 cm from the anode. Such performances fully satisfy the requirements for the upgrade of the ND280 TPC.
The ENUBET project is aimed at designing and experimentally demonstrating the concept of monitored neutrino beams. These novel beams are enhanced by an instrumented decay tunnel, whose detectors ...reconstruct large-angle charged leptons produced in the tunnel and give a direct estimate of the neutrino flux at the source. These facilities are thus the ideal tool for high-precision neutrino cross-section measurements at the GeV scale because they offer superior control of beam systematics with respect to existing facilities. In this paper, we present the first end-to-end design of a monitored neutrino beam capable of monitoring lepton production at the single particle level. This goal is achieved by a new focusing system without magnetic horns, a 20 m normal-conducting transfer line for charge and momentum selection, and a 40 m tunnel instrumented with cost-effective particle detectors. Employing such a design, we show that percent precision in cross-section measurements can be achieved at the CERN SPS complex with existing neutrino detectors.
Glutamate and multiple sclerosis Frigo, M; Cogo, M G; Fusco, M L ...
Current medicinal chemistry,
03/2012, Letnik:
19, Številka:
9
Journal Article
Recenzirano
Multiple sclerosis (MS) has been considered for a long time a typical inflammatory demyelinating disease of the central nervous system due to autoimmunity targeting oligodendrocytes with sparing of ...axons until advanced stages of the disease. For this reason, most of the earliest experimental studies focused on the role of cytokines and chemokines at the site of oligodendrocytes loss and on the importance in MS pathogenesis of classical inflammatory mechanisms. As a result, several attempts to treat MS through reduction of the local inflammatory milieau have been performed, leading to the current "immunomodulatory" treatment of the disease. However, more recently the importance of axonal loss and neurodegeneration even in the earliest stages of MS has been also recognized, and additional or concomitant players have been therefore searched. Evidence is now increasing that excessive glutamate is released at the site of demyelination and axonal degeneration in MS plaques, and the most probable candidates for this cellular release are infiltrating leukocytes and activated microglia. These observations are no longer simply preclinical results obtained in the MS animal model, i.e. experimental allergic encephalomyelitis, but have already been partially confirmed by post-mortem studies and in vivo analysis in MS patients, thus raising the possibility that modulation of glutamate release and transport as well as receptors blockade might be relevant targets for the development of future therapeutic interventions.
The second phase of the T2K experiment is expected to start data taking in autumn 2022. An upgrade of the Near Detector (ND280) is under development and includes the construction of two new Time ...Projection Chambers called High-Angle TPC (HA-TPC). The two endplates of these TPCs will be paved with eight Micromegas type charge readout modules. The Micromegas detector charge amplification structure uses a resistive anode to spread the charges over several pads to improve the space point resolution. This innovative technique is combined with the bulk-Micromegas technology to compose the “Encapsulated Resistive Anode Micromegas” detector. A prototype has been designed, built and exposed to an electron beam at the DESY II test beam facility.
The data have been used to characterize the charge spreading and to produce its map. Spatial resolution better than 600 μm and energy resolution better than 9% are obtained for all incident angles. These performances fulfil the requirements for the upgrade of the ND280 TPC.
An upgrade of the near detector of the T2K long baseline neutrino oscillation experiment is currently being conducted. This upgrade will include two new Time Projection Chambers, each equipped with ...16 charge readout resistive Micromegas modules.
A procedure to validate the performance of the detectors at different stages of production has been developed and implemented to ensure a proper and reliable operation of the detectors once installed. A dedicated X-ray test bench is used to characterize the detectors by scanning each pad individually and to precisely measure the uniformity of the gain and the deposited energy resolution over the pad plane. An energy resolution of about 10% is obtained.
A detailed physical model has been developed to describe the charge dispersion phenomena in the resistive Micromegas anode. The detailed physical description includes initial ionization, electron drift, diffusion effects and the readout electronics effects. The model provides an excellent characterization of the charge spreading of the experimental measurements and allowed the simultaneous extraction of gain and charge spreading information of the modules.
In this paper we describe the performance of a prototype of the High Angle Time Projection Chambers (HA-TPCs) that are being produced for the Near Detector (ND280) upgrade of the T2K experiment. The ...two HA-TPCs of ND280 will be instrumented with eight Encapsulated Resistive Anode Micromegas (ERAM) on each endplate, for a total of 32 ERAMs. This innovative technique allows the detection of the charge emitted by ionization electrons over several pads, improving the determination of the track position.
The TPC prototype has been equipped with the first ERAM module produced for T2K and with the HA-TPC readout electronics chain and it has been exposed to an electron beam at DESY in order to measure spatial and dE/dx resolution. In this paper we characterize the performances of the ERAM and, for the first time, we compare them with a newly developed simulation of the detector response.
Spatial resolution better than 800 μm and dE/dx resolution better than 10% are observed for all the incident angles and for all the drift distances of interest. All the main features of the data are correctly reproduced by the simulation and these performances fully fulfill the requirements for the HA-TPCs of T2K.
Abstract
The main source of systematic uncertainty on neutrino cross section measurements at the GeV scale originates from the poor knowledge of the initial flux. The reduction of this uncertainty to ...1% can be achieved through the monitoring of charged leptons produced in association with neutrinos. The goal of the ENUBET ERC project is to prove the feasibility of such a monitored neutrino beam. In this contribution, the final results of the ERC project, together with the complete assessment of the feasibility of its concept, are presented. An overview of the detector technology for a next generation of high precision neutrino-nucleus cross section measurements, to be performed with the ENUBET neutrino beam, is also given.
The ENUBET experiment is developing a new narrow-band neutrino beam in which the flux and the flavor composition are known at 1
level, and the energy with O(10
) precision. Such a goal is ...accomplished monitoring the associated charged leptons produced in the decay region of the ENUBET facility:
and
from kaons are measured by a segmented calorimeter instrumenting the walls of the decay tunnel, while muon stations after the hadron dump can monitor muons from pions. We report an update on the status of the project.
The ENUBET project is aimed at designing and experimentally demonstrating the concept of monitored neutrino beams. These novel beams are enhanced by an instrumented decay tunnel, whose detectors ...reconstruct large-angle charged leptons produced in the tunnel and give a direct estimate of the neutrino flux at the source. These facilities are thus the ideal tool for high-precision neutrino cross-section measurements at the GeV scale because they offer superior control of beam systematics with respect to existing facilities. In this paper, we present the first end-to-end design of a monitored neutrino beam capable of monitoring lepton production at the single particle level. This goal is achieved by a new focusing system without magnetic horns, a 20 m normal-conducting transfer line for charge and momentum selection, and a 40 m tunnel instrumented with cost-effective particle detectors. Employing such a design, we show that percent precision in cross-section measurements can be achieved at the CERN SPS complex with existing neutrino detectors.
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