THE T2K NEAR DETECTOR AND PARTICLE IDENTIFICATION

A 4π time-of-flight detector for the ND280/T2K upgrade

Journal of Instrumentation ◽

10.1088/1748-0221/17/01/p01016 ◽

2022 ◽

Vol 17 (01) ◽

pp. P01016

Author(s):

A. Korzenev ◽

F. Barao ◽

S. Bordoni ◽

D. Breton ◽

F. Cadoux ◽

...

Keyword(s):

Time Resolution ◽

Plastic Scintillator ◽

Time Of Flight ◽

Particle Identification ◽

Modular Structure ◽

Accelerator Complex ◽

Large Area ◽

Near Detector ◽

Active Neutrino ◽

Cosmic Muons

Abstract ND280 is a near detector of the T2K experiment which is located in the J-PARC accelerator complex in Japan. After a decade of fruitful data-taking, ND280 is scheduled for upgrade. The time-of-flight (ToF) detector, which is described in this article, is one of three new detectors that will be installed in the basket of ND280. The ToF detector has a modular structure. Each module represents an array of 20 plastic scintillator bars which are stacked in a plane of 2.4 × 2.2 m2 area. Six modules of similar construction will be assembled in a cube, thus providing an almost 4π enclosure for an active neutrino target and two TPCs. The light emitted by scintillator is absorbed by arrays of large-area silicon photo-multipliers (SiPMs) which are attached to both ends of every bar. The readout of SiPMs, shaping and analog sum of individual SiPM signals within the array are performed by a discrete circuit amplifier. An average time resolution of about 0.14 ns is achieved for a single bar when measured with cosmic muons. The detector will be installed in the basket of ND280, where it will be used to veto particle originating outside the neutrino target, improve the particle identification and provide a cosmic trigger for calibration of detectors which are enclosed inside it.

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Microanalysis of precipitates in a ferritic steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110234 ◽

1978 ◽

Vol 36 (1) ◽

pp. 618-619

Author(s):

J.M. Titchmarsh

Keyword(s):

Ferritic Steel ◽

Particle Identification ◽

Energy Dispersive ◽

Objective Lens ◽

Ferritic Steels ◽

Replica Technique ◽

X Ray ◽

Large Numbers ◽

Scanning Transmission ◽

Made In

The advances in recent years in the microanalytical capabilities of conventional TEM's fitted with probe forming lenses allow much more detailed investigations to be made of the microstructures of complex alloys, such as ferritic steels, than have been possible previously. In particular, the identification of individual precipitate particles with dimensions of a few tens of nanometers in alloys containing high densities of several chemically and crystallographically different precipitate types is feasible. The aim of the investigation described in this paper was to establish a method which allowed individual particle identification to be made in a few seconds so that large numbers of particles could be examined in a few hours.A Philips EM400 microscope, fitted with the scanning transmission (STEM) objective lens pole-pieces and an EDAX energy dispersive X-ray analyser, was used at 120 kV with a thermal W hairpin filament. The precipitates examined were extracted using a standard C replica technique from specimens of a 2¼Cr-lMo ferritic steel in a quenched and tempered condition.

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