Current Status and Future Developments of Micromegas Detectors for Physics and Applications

Round 1

Reviewer 1 Report

The paper is in my option very good.

I have only a few minor remarks:

• All abbreviations shall be explained, i.e. PCB, SU8 are not explained.
• All abbreviations shall be explained only once, i.e. TPC is explained twice.
• Maybe a list of all abbreviation could be added at the end of the paper (see MDPI template)
• Line 488 semicolon is orphaned
• Line 493 2 x 10^3 - times sign is missing

The paper presents a very broad spectrum devoted to Micromegas, therefore I would recommend extending the section Conclusions which is rather tiny in contrast to the rest of it.

Author Response

The authors would like to thank the referee for reviewing the article.

All remarks have been taken into consideration. A list of all abbreviation have been added after the "Acknowledgments" section. The "Conclusions" section has been extended.

Reviewer 2 Report

Introduction

The findings presented in the manuscript entitled “Current status and future developments of Micromegas detectors for physics and applications” are very interesting and have important implications in several fields, as highlighted by the authors since the beginning of the paper.

The introduction provides a good, generalized background of the topic, outlining that the present paper is going to review the Micromegas detectors for physics and applications. The main concepts included in the introduction give the reader an appreciation of the wide range of applications for this technology. Lines 41÷56 detail the main advantages of this versatile type of detector, listing the most important performances.

I think the motivations for this review are clear and well defined, and the mentioned references are essential for a detailed analysis of the several and various steps which brought to the present status and development of Micromegas detectors. In particular, the characteristics of the detector and the several solutions implemented to adapt them to different environments and multiple scopes are properly taken into consideration and the reader expects they are duly addressed in the following (as it is, indeed, in the style of a precise review, as anticipated by the authors).

Methods in the Review Paper

The review focuses on a well-established section on Micromegas fabrication techniques, in order to present the main advantages, drawbacks and usages of the different types of detectors.

In particular, Section 2 is devoted to Micromegas typologies and employs according to their features and the experiment focus (lines 86÷89; lines 139÷145; lines 164÷169; lines 196÷204).

The authors devoted an entire section, Section 3, to the use of Micromegas as a tracker in CLAS12 and COMPASS. After a detailed, but concise description of the detectors main features, experiment main purposes and critical issues to be overcome, the technical solution are presented, supported by useful figures (Figures 8 and 9), layouts, explanations.   

Section 4 focuses on the Micromegas application in the high energy physics ATLAS environment. The way the section is established and the main issues discussed is very well established and the future perspectives are really appreciated. The core of the section in lines 306÷318 details the driving specifications and the consequent constraints for these detectors. Figure 10, 11, 12 and Table 1 are useful to guide the reader in understanding how the technical challenges have been faced and the solutions implemented.

Since the style of the review does not allow to investigate or explain in detail the several experiments where Micromegas have been implemented, the duly reported references help the reader in following up the topics and deepen them, if needed, browsing the mentioned literature.

Section 6 entirely focused on the Micromegas readout of TPCs deals in detail with fields of usage, features to be exploited depending on the main purposes, original solutions implemented, even passing through the proper gas mixture to be adopted (lines 404÷413).

All the mentioned detectors and experiments, with corresponding results, presented and detailed in related papers, are here clearly explained with the support of figures: every figure is properly cited in the paper, in particular the experimental layouts, assembly and set up are depicted in Figures from 13 to 20, being absolutely helpful in guiding the reader through the review.

Section 7 is devoted to Micromegas for neutron detection, while Section 8 is a short but complete summary of such detectors use for UV detection.

In Section 9 another important and useful advantage of Micromegas application is duly addressed: the precise timing we could obtain with proper solutions and implementations (Figure 26).

Concerning references, the cited literature is balanced and relevant to the study.

Finally, despite the overall review is well established and balanced, giving the due space to the several and different fields where Micromegas can be employed and exploited, the Conclusions in Section 10 are definitely poor and not well addressed. I would have appreciated much more consideration in briefly going through the list of the Sections (i.e. dealing with the physics and the related applications), outlining the main advantages and groundbreaking results obtained so far, highlighting the future perspectives, leveraging on weak points and focusing on the Micromegas breakthrough.

Minor Comments

To publish this paper in your target journal, the following minor revisions are advised, all related to layout of pages including text and figures:

• Line 36: demonstrate instead of demonstrating.
• Line 102: “the mesh is placed on THE top”. Article to be added.
• Line 136: I recommend to use the verb SHOWS instead of has “This SHOWS as a result some degradation…”.
• Line 216: ALLOWS instead of allow (“and ALLOWS a better reconstruction”).
• Line 240: SUPPORTS instead of support (“A three sectors carbon structure SUPPORTS…”).
• Figure 13, caption, second line: CORRESPOND instead of corresponds.
• Line 437: delete the second article THE at the end of the line.
• Line 441-442: in the final formatting I would recommend to keep units next to related numbers (“10 to 15 cm”) and on the same line.
• Line 456-457: in the final formatting I would recommend to keep units next to related numbers (“100 µm”) and on the same line.
• Line 472: delete space before the colon (after the word “adopted”).
• Line 477: delete space before the colon (after the word “met”). On the same line, no uppercase “A” after the colon.
• Line 487-488: delete space before the colon (after the word “configuration”).
• Line 497: PREVENT instead of prevents.
• Line 500: in the Sub-section title, delete space before the colon (after the word “searches”).
• Line 552: “GridPix is A VERY interesting” instead of “is very a interesting”.
• Line 612: add a comma before “as for example”.
• Line 643: add the colon before the list below.
• Lines 644÷649: no uppercase for the first word (the instead of The). Put semicolon in lines 645 and 648, to close the sentence, not full sop.
• Line 655: add a comma before “as illustrated in figure 21”.
• Line 673: delete the article A at the end of the line.
• Figure 23, caption: last line, add a comma before “as explained in the text”.
• Line 728: add a comma before “but also increases”.
• Line 810: I recommend to keep in brackets measure and uncertainties (24.0±0.3) ps.
• Line 813: I recommend to keep in brackets measure and uncertainties (10.40±0.40) photoelectrons per muon and on the same line.
• Line 855: HAS instead of was (“HAS been used”).

Major Comments

My only concern is the poorness of the Conclusions. I would recommend to re-write this important Section, if possible, being more precise and touching all the aforementioned applications, dwelling on future perspectives (as the authors did report in the previous well established Sections).

I would have appreciated much more consideration in briefly going through the list of the Sections (i.e. of the physics and the related applications), outlining the main advantages and groundbreaking results obtained so far, highlighting the future perspectives, leveraging on weak points and focusing on the Micromegas breakthrough.

Author Response

The authors would like to thank the referee for reviewing the article.

All remarks have been taken into consideration. The "Conclusions" section has been extended to briefly address the developments presented in previous subsections.

Round 2

Reviewer 2 Report

The findings presented in the manuscript entitled “Current status and future developments of Micromegas detectors for physics and applications” are very interesting and have important implications in several fields, as highlighted by the authors since the beginning of the paper.

The main concepts are well introduced and addressed and the Conclusions summarize properly the main findings. I really appreciate that the authors accept my advice and the Conclusions have been duly re-written.