arXiv subjects

F. Magniette

Publications and source records attributed to F. Magniette.

7 recordsLinked to original sources

arXiv2020

Particle Identification Using Boosted Decision Trees in the Semi-Digital Hadronic Calorimeter Prototype

The CALICE Semi-Digital Hadronic CALorimeter (SDHCAL) prototype using Glass Resistive Plate Chambers as a sensitive medium is the first technological prototype of a family of high-granularity calorimeters developed by the CALICE collaboration to equip the experiments of future leptonic colliders. It was exposed to beams of hadrons, electrons and muons several times in the CERN PS and SPS beamlines between 2012 and 2018. We present here a new method of particle identification within the SDHCAL using the Boosted Decision Trees (BDT) method applied to the data collected in 2015. The performance of the method is tested first with Geant4-based simulated events and then on the data collected by the SDHCAL in the energy range between 10 and 80~GeV with 10~GeV energy steps. The BDT method is then used to reject the electrons and muons that contaminate the SPS hadron beams.

physics.ins-det↗

arXiv2019

Beam test performance of the highly granular SiW-ECAL technological prototype for the ILC

The technological prototype of the CALICE highly granular silicon-tungsten electromagnetic calorimeter (SiW-ECAL) was tested in a beam at DESY in 2017. The setup comprised seven layers of silicon sensors. Each layer comprised four sensors, with each sensor containing an array of 256 $5.5\times5.5$ mm$^2$ silicon PIN diodes. The four sensors covered a total area of $18\times18$ cm$^2$, and comprised a total of 1024 channels. The readout was split into a trigger line and a charge signal line. Key performance results for signal over noise for the two output lines are presented, together with a study of the uniformity of the detector response. Measurements of the response to electrons for the tungsten loaded version of the detector are also presented.

physics.ins-det↗

arXiv2018

Commissioning of the highly granular SiW-ECAL technological prototype

In this article we describe the commissioning and a first analysis of the the beam test performance of a small prototype of a highly granular silicon tungsten calorimeter. The prototype features detector elements with a channel number similar to that envisaged for e.g. the ILD Detector of the International Linear Collider (ILC). The analysis demonstrates the capability of the detector to record signals as low as 0.5 MIP. Further, no loss of performance has been observed when operating the detector in a high magnetic field.

physics.ins-det↗

arXiv2018

Hadronic Energy Resolution of a Combined High Granularity Scintillator Calorimeter System

This paper presents results obtained with the combined CALICE Scintillator Electromagnetic Calorimeter, Analogue Hadronic Calorimeter and Tail Catcher & Muon Tracker, three high granularity scintillator-SiPM calorimeter prototypes. The response of the system to pions with momenta between 4 GeV/c and 32 GeV/c is analysed, including the energy response, resolution, and longitudinal shower profiles. The results of a software compensation technique based on weighting according to hit energy are compared to those of a standard linear energy reconstruction. The results are compared to predictions of the GEANT4 physics lists QGSP_BERT_HP and FTFP_BERT_HP.

physics.ins-det↗

arXiv2018

Performance study of SKIROC2/A ASIC for ILD Si-W ECAL

The ILD Si-W ECAL is a sampling calorimeter with tungsten absorber and highly segmented silicon layers for the International Large Detector (ILD), one of the two detector concepts for the International Linear Collider. SKIROC2 is an ASIC for the ILD Si-WECAL. To investigate the issues found in prototype detectors, we prepared dedicated ASIC evaluation boards with either BGA sockets or directly soldered SKIROC2. We report a performance study with the evaluation boards, including signal-to-noise ratio and TDC performance with comparing SKIROC2 and an updated version, SKIROC2A.

physics.ins-det↗

arXiv2017

Performance measurement of HARPO: a Time Projection Chamber as a gamma-ray telescope and polarimeter

We analyse the performance of a gas time projection chamber (TPC) as a high-performance gamma-ray telescope and polarimeter in the e$^+$e$^-$ pair creation regime. We use data collected at a gamma-ray beam of known polarisation. The TPC provides two orthogonal projections $(x,z)$ and $(y,z)$ of the tracks induced by each conversion in the gas volume. We use a simple vertex finder in which vertices and pseudo-tracks exiting from them are identified. We study the various contributions to the single-photon angular resolution using Monte Carlo simulations and compare them with the experimental data and find that they are in excellent agreement. The distribution of the azimutal angle of pair conversions shows a bias due to the non-cylindrical-symmetric structure of the detector. This bias would average out for a long duration exposure on a space mission, but for this pencil-beam characterisation we have ensured its accurate simulation by a double systematics control scheme, data taking with the detector rotated at several angles with respect to the beam polarisation direction and systematics control with a non-polarised beam. We measure, for the first time, the polarisation asymmetry of a linearly polarised gamma-ray beam in the low energy pair creation regime. This sub-GeV energy range is critical for cosmic sources as their spectra are power laws which fall quickly as a function of increasing energy. This work could pave the way to extending polarised gamma-ray astronomy beyond the MeV energy regime.

astro-ph.IM↗

arXiv2017

SiW ECAL for future $e^+e^-$ collider

Calorimeters with silicon detectors have many unique features and are proposed for several world-leading experiments. We discuss the tests of the first three 18x18 cm$^2$ layers segmented into 1024 pixels of the technological prototype of the silicon-tungsten electromagnetic calorimeter for a future $e^+e^-$ collider. The tests have beem performed in November 2015 at CERN SPS beam line.

physics.ins-det↗