Thermoluminescence, a Critical Reappraisal of Successes, Uncertainties, and a Look to the Future

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The text is well written and covers all aspects of the thermoluminescence technique. The challenges related to systematic erros both in data collection, signal processing , and models have ben presented and discussed. The authors have also made suggestions to improve on numerous aspects of experimentation and modelling.

Author Response

Please see the attached file. Many thanks! 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

General Comments

This manuscript provides a valuable and thoughtful overview of several long-standing methodological and conceptual challenges in thermoluminescence (TL) research. The authors’ extensive experience in TL data acquisition, spectral analysis, and defect characterization is clearly reflected throughout the text. Overall, the manuscript has the potential to serve as an informative resource for both new and experienced researchers in the TL community.

The following comments identify points that require revision in order to improve the clarity, completeness, and overall balance of this review article.

1. In introduction, the following passage presents a very clear and assertive statement:

“Surprisingly, this is definitely not the case. Indeed, the data collection methods are invariably flawed in many aspects, and the proposed mechanisms of the process are vastly idealised and/or deliberately over simplified.”

In this context, it may help the readers if the authors could briefly indicate some representative examples of the systematic errors or oversimplifications they have in mind.

For instance, mentioning well-known issues such as temperature lag, spectral overlap, retrapping assumptions, or the neglect of long-range interactions—even just as illustrative examples—would make the basis of this assertion more immediately accessible to readers.

2. In Section 2, the authors describe important improvements achieved through the development of their own TL measurement systems, such as the transition from PMT-based detectors to imaging photon detectors (IPDs), and these long-term contributions are clearly demonstrated.

However, in order to enhance the completeness and balance expected of a review article, it may be helpful for the authors to briefly touch upon a broader range of TL measurement systems reported in the literature, not only those developed within their own group.

3. The manuscript provides a clear and valuable discussion of issues related to heating-rate dependence and temperature-measurement uncertainties in TL analysis. I found the emphasis on the importance of low heating rates particularly meaningful.

In this context, there have been several earlier studies that explicitly analyzed TL glow curves at very slow heating rates (often with “slow rate” in the title). These works may align well with the points raised in the present review, especially regarding changes in TL parameters and the appearance of additional glow-curve components that become evident only under slow heating conditions.

If the authors feel it would be helpful, they might consider referring to a few representative studies in this area, such as:

・https://doi.org/10.1063/1.1947898

・https://doi.org/10.1063/1.2173033

・https://doi.org/10.1063/1.2359134

・https://doi.org/10.1016/j.radmeas.2007.11.037

・https://doi.org/10.1007/s10854-023-11378-7

・https://doi.org/10.18494/SAM.2016.1359

・https://doi.org/10.1007/s10854-023-11378-7

Incorporating some of these slow-rate studies is, of course, optional, but doing so may enrich the historical context of the review and further illustrate the significance of slow-heating-rate measurements in obtaining reliable TL parameters.

4. In Section 6, the authors present an important critique of the limitations of traditional single-trap and single-center models. This discussion is valuable, and the recognition of the shortcomings of classical kinetic approaches is highly relevant to current TL research.

If the authors consider it appropriate, the section could be further strengthened by briefly acknowledging that several newer modelling frameworks have been proposed in recent years to address these limitations. 

Author Response

Please see the attached file. Many thanks! 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors This review summarizes the evaluation protocols and underlying mechanisms of thermoluminescence (TL), which is widely used in radiation dosimetry and archeological dating. Although TL is a long-known phenomenon, understanding its basis in defect chemistry and the kinetic model is highly valuable for the development of novel dosimetry materials. Furthermore, the manuscript provides a detailed discussion of temperature measurement errors and noise characteristics, making it a highly informative resource for readers ranging from beginners to experts in TL measurements. The manuscript is generally acceptable; however, some minor revisions are requested as outlined below.
1. In the introduction, the authors state that they minimize effects of large-scale defects such as dislocations, grain and phase inclusions, and the influence of surface contaminations. However, the order of magnitude of defect concentrations not considered within these simple models is critical for assessing whether they can be neglected. If the authors have any insights regarding these defect concentrations, providing such information would be highly beneficial for readers.
2. There are inconsistencies in the notation of the term "imaging photon detector (IPD)" throughout the manuscript. It is recommended to ensure consistent usage of this term across the entire text.
3. Although Figure 2a appears to be a very important figure in this context, it may be challenging for readers to interpret at a glance. It is recommended to include a brief explanation in the caption to guide readers on how to interpret the figure.
4. On pages 10, 17, and 19, the same sentences are repeated in several paragraphs.
5. Regarding Figure 10, the authors state that the decrease in TL intensity with increasing Fe ion concentration correlates with the size of impurity clusters. How does this phenomenon differ from the concentration quenching typically observed in conventional phosphors doped with activator ions? For readers from broader fields, it would be helpful to include a brief explanation of this distinction.
6. On page 14, the authors state that the cubic Mg2SiO4 lattice expands with increasing Tb3+ concentration. However, judging from the XRD patterns shown in Figure 11a, Mg2SiO4 has an orthorhombic lattice rather than a cubic one.
7. In Table 1, the labels for peak temperature and intensity are currently arranged vertically, which makes it somewhat difficult to read the values in each column. It is recommended to improve the table formatting.
8. In section 4.5, the authors state: "one possible route would be to use Boltzmann thermometry on an insulator doped with two rare-earth ions and excited with a UV laser beam at a wavelength that is blocked in the spectral data collection." Boltzmann thermometry typically determines temperature based on the Boltzmann distribution between thermally coupled energy levels of a single rare-earth ion. Therefore, the expression "two rare-earth ions" should be carefully checked in this context and possibly revised to "single rare-earth ion."

9. Regarding Figure 15, the broken arrow of photon emission overlaps with the lines representing deep traps, which makes the figure difficult to interpret. It is recommended to improve the figure's clarity by adjusting the layout or spacing.
10. TL is significantly affected by thermal quenching of luminescence; therefore, when thermal quenching cannot be neglected at high temperatures, a correction using a quenching curve is required. This aspect is extremely important in TL glow curve analysis and should be explicitly mentioned in the manuscript.

Author Response

Please see the attached file. Many thanks! 

Author Response File: Author Response.pdf