Minimum fluence required to achieve measurable emission signals
Note: Usually the breakdown-threshold fluence is orders of magnitude higher than the ablation-threshold fluence.
Source: PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 714 (https://doi.org/10.1515/pac-2019-0203)