Robustness of analogue Hawking radiation in cavities with moving boundaries

Abstract In this work we explore the limitations and robustness of thermal radiation in dynamical Casimir systems serving as analogues for Hawking radiation. Through detailed numerical analysis, we characterize particle production spectra in cavities with moving boundaries under various configurations. We establish a thermality criterion based on the detailed balance condition, and we find that thermal signatures emerge in the spectrum of specific expanding cavity configurations, although they are highly dependent on frequency bands and acceleration parameters. Furthermore, our framework successfully verifies previous theoretical predictions, demonstrating that non-standard statistical distributions (such as Fermi–Dirac) can be robustly reproduced in finite confined settings despite the underlying field being purely bosonic. Further, we derive fitting expressions that quantify deviations from idealized thermal spectra through grey-body factors, revealing oscillatory behaviours tied to acceleration duration. Our results identify experimental setups that can reliably reproduce the thermal production akin to that from gravitationally-induced phenomena and quantify how finite-size effects and transient dynamics modify the expected thermal distributions, providing a comprehensive framework for distinguishing genuine Hawking-like radiation from experimental artefacts.