Highly-parallelized simulation of a pixelated LArTPC on a GPU

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

Measurements of trace gases in the tropical tropopause layer

A unique dataset of airborne in situ observations of HCl, O 3, HNO 3, H 2O, CO, CO 2 and CH 3Cl has been made in and near the tropical tropopause layer (TTL). A total of 16 profiles across the tropopause were obtained at latitudes between 10°N and 3°S from the NASA WB-57F high-altitude aircraft flying from Costa Rica. Few in situ measurements of these gases, particularly HCl and HNO 3, have been reported for the TTL. The general features of the trace gas vertical profiles are consistent with the concept of the TTL as distinct from the lower troposphere and lower stratosphere. A combination of the tracer profiles and correlations with O 3 is used to show that a measurable amount of stratospheric air is mixed into this region. The HCl measurements offer an important constraint on stratospheric mixing into the TTL because once the contribution from halocarbon decomposition is quantified, the remaining HCl (>60% in this study) must have a stratospheric source. Stratospheric HCl in the TTL brings with it a proportional amount of stratospheric O 3. Quantifying the sources of O 3 in the TTL is important because O 3 is particularly effective as a greenhouse gas in the tropopause region

The Irish Catholic Female Religious and the Transnationalisation of Care: An Historical Perspective

The transnational turn in sociological studies of care and welfare is generating new research agendas focused on the circulation and hybridisation of social ideas, values, practices, resources, relations and provision across political borders. This article examines neglected aspects within care transnationalisation research by focusing on the involvement of the Irish Catholic female religious from a historical perspective. Successive histories of female religious care migrations reveal Catholic religious orders of women to be the epitome of a flexible, hyper-mobile labour force. The nature of religious life combined with the social, cultural, economic and organisational capacities of the Catholic Church rendered female religious orders pivotal to the formation of border-spanning care labour networks through which Catholic ideas and practices of carework circulated to forge and sustain links and connections between Ireland and many other places worldwide. The discussion emphasises the necessity of attending to ‘counter-geographies’ of global care migrations, the interlocking nature of religious and secular care migration and historical antecedents of contemporary care transnationalisation processes in future research programmes