The manuscript presents a solid structure, a consistent methodological approach, and reflects current best practices in Electron Spin Resonance (ESR) dating of fossil tooth enamel. The careful sample preparation, controlled administration of radiation doses, and spectral decomposition using simulated annealing all demonstrate a high level of experimental rigor. I recommend the manuscript for publication, suggesting only that a few points be more clearly addressed or incorporated into the text, as outlined in the comments below.
1) The manuscript addresses the presence of pre-existing radicals (notably NOCORs) and discusses their evolution under gamma irradiation. However, it does not clearly state whether a systematic background correction or quantification was performed prior to irradiation
2) It is noted that the irradiation doses applied to the Jebel Irhoud (IR) and Broken Hill (BH) samples differ substantially, which can be justified by the differences in the concentration and behavior of ESR radicals, particularly the non-oriented CO₂⁻ radicals (NOCORs), exhibiting distinct profiles between the two samples. These differences directly influence the ESR signal intensity and its response to irradiation, requiring tailored dose ranges to ensure that measurements remain within the linear portion of the dose-response curve for each sample. This approach is both appropriate and necessary for accurate estimation of the equivalent dose and, consequently, age determination. It is recommended that the authors explicitly confirm this rationale in the manuscript, clarifying whether the selection of irradiation dose ranges was based on the specific characteristics of each sample to ensure the comparative validity of the results.
3) Although the manuscript mentions that the Jebel Irhoud (IR) sample measurements were conducted exclusively in the Y-configuration, unlike the three orientations for the Broken Hill (BH) sample, there is no detailed discussion about the potential consequences of this limitation on angular resolution and the robustness of the spectral decomposition. This restriction may directly affect the accuracy of the ESR radical analysis, particularly in the identification and quantification of oriented radicals (AICORs), thereby compromising the comparison between the two datasets. I recommend that the authors include a critical assessment of this impact to strengthen the interpretation of their results.
4) The methodology section does not specify whether the ESR spectrometer was calibrated using recognized reference standards, nor does it mention any assessment of measurement reproducibility. I recommend that the authors provide information on equipment calibration and reproducibility tests, or justify their absence, to enhance the robustness of the experimental method.