Paper draft HIN-18-018
CWR comments by Mykola Savitskyi
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lines 77-79: It is unclear to which coverage in pseudorapidity the HF detectors are referring to. Is it the same as the one defined in lines 51-53? Why then defining this coverage again in line 90?
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lines 82: It would be interesting to know why Pythia6 is used as nominal for this measurement and not, e.g., Pythia8.
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lines 93-95: Which quality criterion was used to define bins in centrality as they are? This criterion has to be specified in detail.
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chapter 4 (lines 104 - 137): Authors should make clear which parts of the jet and track reconstruction are common for pp and PbPb collisions, and which are unique. The current structure of the description is convoluted. We would recommend describing first what is common, or a procedure for one type of collisions, and then summarize what is different for the other type of collisions.
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line 96-97: We recommend to rephrase this sentence, especially avoid usage of "binary" (to be replaced with a word that provides more clarity).
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line 156: A detailed description of the final-state particle level has to be added.
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line 176-179: Why variations of 50% are justified to provide the best estimate regarding the number of iterations?
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line 179-182: One needs to specify the exact number of iterations used for each considered selections.
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chapter 8 (lines 219-263): Many numbers used for the assessment of systematic uncertainties are given in the text without mentioning their origin, e.g. references, studies, etc.
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line 246: This is the first time when the regularization is mentioned in the paper. Regularization has to be described in the unfolding chapter, as well as the way to determine its strength.
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Figure 2: The shaded area is visible on the plot, but is never properly described. We believe that crosses for Pythia6 could be replaced with other markers (lines) to provide better visibility.
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lines 318-320 + lines 322-326: Authors state that they observe different effects w.r.t. to previous measurements by CMS, but never provide a proper discussion on this discrepancy.
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lines 332-335: One can understand that conclusions based on PbPb measurements, i.e. results are independent w.r.t. collision centrality, are also true for pp collisions at different centralities. However, in this paper, technically, only *one* centrality was measured for pp collisions. One could simply state conclusions for PbPb separately and only then specify that distributions from pp measurements follow similar trends as the ones observed from the PbPb measurements, as well as specifying what could this mean physics-wise (e.g. similar to what is done in lines 321-323).