Bounds on colored and dissipative collapse models
In plain words
If the collapse noise has a 'color' (it stops above some frequency) or the collapse loses energy to a finite effective temperature, the X-ray bounds weaken greatly. Low-frequency tests with heavy oscillators then become the main probes.
Precise statement
For CSL with noise correlation cutoff frequency $\Omega$ (colored) and/or collapse-noise temperature $T_{\mathrm{CSL}}$ (dissipative), determine the excluded region of $(\lambda, r_{C}, \Omega, T_{\mathrm{CSL}})$ from levitated and clamped mechanical oscillators, gravitational-wave detectors, bulk heating and interferometry, and whether parameters giving macroscopic collapse survive when $\Omega$ lies below the X-ray frequency range.
What would settle it
Low-frequency force-noise or heating measurements sensitive to collapse-induced diffusion that exclude or detect it across the colored and dissipative parameter space.
Status in the literature
Unverified note
XENONnT noted in 2025 that colored and dissipative extensions retain a wide unexplored region; levitated-optomechanics bounds on linear-friction dissipative models appeared in 2024 (arXiv:2401.04665).