2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/175622The Bardeen-Cooper-Schrieffer (BCS) mean-field theory of the pairing interaction breaks down for nuclei and ultra-small metallic grains (nanoparticles). Finite-temperature pairing correlations in such finite-size systems can be calculated beyond the BCS theory in an auxiliary-field Monte Carlo approach. We identify thermal signatures of pairing correlations in both nuclei and nanoparticles that depend on the particle-number parity.9 pages, 3 figures; to appear in the Proceedings of the Second International Conference on Collective Motion in Nuclei Under Extreme Conditions (COMEX2)Nuclear TheorySuperconductivitytext