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Systematic uncertainties in accelerator oscillation neutrino experiments arise mostly from nuclear models describing neutrino-nucleus interactions. To mitigate these uncertainties, we can study neutrino-nuclei interactions with detectors possessing enhanced hadron detection capabilities at energies below the nuclear Fermi level. Gaseous detectors not only lower the particle detection threshold but also enable the investigation of nuclear effects on various nuclei by allowing for changes in the gas composition. This approach provides valuable insights into the modelling of neutrino-nucleus interactions and significantly reduces associated uncertainties. Here, we discuss the design and first operation of a gaseous argon time projection chamber optically read. The detector operates at atmospheric pressure and features a single stage of electron amplification based on a thick GEM. Here, photons are produced with wavelengths in the vacuum ultraviolet regime. In an optical detector the primary constraint is the light yield. This study explores the possibility of increasing the light yield by applying a low electric field downstream of the ThGEM. In this region, called the electroluminescence gap, electrons propagate and excite the argon atoms, leading to the subsequent emission of photons. This process occurs without any further electron amplification, and it is demonstrated that the total light yield increases up to three times by applying moderate electric fields of the order of 3~kV/cm. Finally, an indirect method is discussed for determining the photon yield per charge gain of a ThGEM, giving a value of 18.3 photons detected per secondary electron.

We examine the dynamics of superconducting vortices with two-fold anisotropic interaction potentials driven over random pinning and compare the behavior under drives applied parallel and perpendicular to the anisotropy direction. The number of topological defects reaches a maximum near depinning and then drops with increasing driving force as the vortices form one-dimensional chains. This coincides with a transition from a pinned nematic to a moving smectic aligned with the soft direction of the anisotropy. The system is generally more ordered when the drive is applied along the soft direction of the anisotropy, while for driving along the hard direction, there is a critical value of the anisotropy above which the system remains aligned with the soft direction. We also observe hysteresis in the dynamics, with one-dimensional aligned chains persisting during a decreasing drive sweep to drives below the threshold for chain formation during the increasing drive sweep. More anisotropic systems have a greater amount of structural disorder in the moving state. For lower anisotropy, the system forms a moving smectic-A state, while at higher anisotropy, a moving nematic state appears instead., Comment: 13 pages, 11 figures