Report on the quality of the LHCb-Muon four-gap MWPC produced at LNF

The LNF-LHCb team produced 185 four-gap Multi-Wire Proportional Chambers (MWPC). In this note we report the summary of the results of the panel quality controls and of the measurements performed on the assembled detector

Carbon nanotubes as target for directional detection of light WIMP

In this paper I will briefly introduce the idea of using Carbon Nanotubes (CNT) as target for the detection of low mass WIMPs with the additional information of directionality. I will also present the experimental efforts of developing a Time Projection Chamber with a CNT target inside and the results of a test beam at the Beam Test Facility of INFN-LNF.Comment: 3 figures, IFAE2017 poster session proceeding

Measurements of the Cerenkov light emitted by a TeO2 crystal

Bolometers have proven to be good instruments to search for rare processes because of their excellent energy resolution and their extremely low intrinsic background. In this kind of detectors, the capability of discriminating alpha particles from electrons represents an important aspect for the background reduction. One possibility for obtaining such a discrimination is provided by the detection of the Cerenkov light which, at the low energies of the natural radioactivity, is only emitted by electrons. In this paper, the results of the analysis of the light emitted by a TeO2 crystal at room temperature when transversed by a cosmic ray are reported. Light is promptly emitted after the particle crossing and a clear evidence of its directionality is also found. These results represent a strong indication that Cerenkov light is the main, if not even the only, component of the light signal in a TeO2 crystal. They open the possibility to make large improvements in the performance of experiments based on this kind of material

Measurements and optimization of the light yield of a TeO2_2 crystal

Bolometers have proven to be good instruments to search for rare processes because of their excellent energy resolution and their extremely low intrinsic background. In this kind of detectors, the capability of discriminating alpha particles from electrons represents an important aspect for the background reduction. One possibility for obtaining such a discrimination is provided by the detection of the Cherenkov light which, at the low energies of the natural radioactivity, is only emitted by electrons. This paper describes the method developed to evaluate the amount of light produced by a crystal of TeO$_2$ when hit by a 511 keV photon. The experimental measurements and the results of a detailed simulation of the crystal and the readout system are shown and compared. A light yield of about 52 Cherenkov photons per deposited MeV was measured. The effect of wrapping the crystal with a PTFE layer, with the aim of maximizing the light collection, is also presented

Study of the performance of the LHCb MWPC with cosmic rays

In this note we report the results of measurements performed with cosmic rays on different LHCb Muon Chambers. The main characteristics of the chambers have been investigated as a function of the high voltage value in order to achieve a better comprehension of the detector performance both for optimizing the chamber working conditions on the experimental apparatus and for providing useful information for the Monte Carlo simulation

Gas leakage and HV test procedure for the INFN Muon MWPCs

The Muon MWPCs produced by INFN laboratories are subject to gas leakage and HV tests before the installation on the LHCb experiment. The test procedure and the software tools developed are described in this paper

ELMB Microcontroller Firmware and SCADA Integration for the LHCb Muon Detector Readout Control System

The LHCb system requires high efficiency muon detection into LHC bunch crossing: 95% into a 25 ns time window. To reach such efficiency many parameters of the detector readout apparatus have to be calibrated and adjusted and its channels must be aligned in time. In addition, essential characteristics must be monitored to guarantee a good working condition of the apparatus (to avoid loss of efficiency and to minimize systematic errors). As the number of the muon readout parameters is extremely high (∼700000 registers), a system able to process information in parallel is required: 122000 readout channels will be controlled by about 600 microcontrollers and 6 computers. The complexity of such an apparatus requires the use of a distributed system. For this a Supervisory Control And Data Acquisition (SCADA) based system is being developed to control the entire detector readout equipment. Moreover, a Finite State Machine (FSM) implementation is being developed to integrate the Detector Readout Control (DRC) into the LHC Experiment Control System (ECS)

Silicon Photo-Multiplier radiation hardness tests with a beam controlled neutron source

We report radiation hardness tests performed at the Frascati Neutron Generator on silicon Photo-Multipliers, semiconductor photon detectors built from a square matrix of avalanche photo-diodes on a silicon substrate. Several samples from different manufacturers have been irradiated integrating up to 7x10^10 1-MeV-equivalent neutrons per cm^2. Detector performances have been recorded during the neutron irradiation and a gradual deterioration of their properties was found to happen already after an integrated fluence of the order of 10^8 1-MeV-equivalent neutrons per cm^2.Comment: 7 pages, 6 figures, Submitted to Nucl. Inst. Meth.