DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 $$\times $$ ×  6 $$\times $$ ×  6 m$$^3$$ 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019–2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

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A real time empirical mode decomposition (EMD) algorithm based ultrasonic imaging system has been developed for non-destructive testing (NDT) applications. It is difficult to implement the EMD based signal processing algorithm in real time because it is totally a data-driven process which comprises numerous sifting operations. In this paper, the EMD algorithm has been implemented in the visual software environment. The EMD implementation encompasses two types of interpolation methods: piecewise linear interpolation (PLI) and cubic spline interpolation (CSI). The cubic spline tridiagonal matrix has been solved by using the Thomas algorithm for real time processing. The total time complexity functions for both the implemented PLI and CSI based EMD methods have been computed. For the signal filtering, the partial reconstruction algorithm has been adopted. The baseline correction and noise filtering applications have been presented using an EMD based visual software. The real time practicability and the efficiency of this method have been validated through ultrasonic NDT experimentation for improvement in the time domain resolution of the ultrasonic A-scan raw data. The practical results show that in the noisy environment, it is possible to enhance the signal-to-noise ratio for the visualization and identification of ultrasonic pulse-echo signals in real time.

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype.

The second and final version of ColdADC, called ColdADC_P2, is presented. ColdADC_P2 is a 16-channel, 12-bit, 2 MS/s Digitizer ASIC intended for use inside the DUNE Far Detector. ColdADC_P2 contains two 16 MS/s Pipelined ADCs that each digitizes the output of 8 sample-and-hold amplifiers. Because the application requires immersion in liquid argon, ColdADC_P2 was developed using specialized design techniques for long-term reliability in cryogenic environments and a customized cryogenic standard cell library. ColdADC_P2, with a die area of approximately 52.4 mm 2 and fabricated in 65 nm CMOS technology, achieves 130 µV-rms noise performance and 11.8-bit ENOB at a temperature of 77 K, with channel-to-channel crosstalk of < 0.06% while dissipating 338 mW (21 mW per channel). Residual nonlinearity that is consistent with dielectric absorption in the capacitors internal to the ADC is corrected using a lookup table.