Questa è una vecchia versione del documento!
http://cms.cern.ch/cds/EXO-16-025
Dear authors, ARC, congratulations on this well-written, clear paper. Below we have some questions/comments to your attention.
Best wishes for a speedy publication. The Torino group
Type B comments
1. The hardest part of the analysis, to the non-expert reader, seems to be the accurate identification of Z decays coming from merged jets. To convince that the jet substructure identification works, a check on data would be appropriate, if possible. For example, one could measure the ratio Z→jj / Z→mu+mu- with merged jets, taking into account the appropriate efficiencies, and check that the ratio of branching ratios is consistent with expectations. If something like this was done, it is worth mentioning, if not, please consider a similar test.
2. In the discussion of systematic uncertainties, it is not clear how b-tagging, the uncertainty on efficiency of which is up to 60%, can increase the sensitivity by 50%. Can you explain ? Table 2 is very important, but not very clear in understanding the origin and effect of the uncertainties.
Type A comments
L4 Invert : “Searches … are of particular interest”
L 77 “ 170 or 180 GeV” → (180) GeV
L 82 “corrected for zero suppression effects” → the ecal corrections are so many and complicated that I would not mention zero suppression, which to my knowledge is irrelevant at pt>150 GeV
L 83-88 I understand this is boilerplate PF descriptive text, but why bother describing electron and muon reconstruction, which are not used in this analysis ?
L111-112 if possible add a sentence to explain briefly why two different algorithms are chosen at 8 and 13 TeV
L132-141 hard to understand
L187 acceptance mentioned here for the first time, it is not defined and you don't say how it is calculated
Throughout the paper subjet → sub-jet
L207 - 208 I would omit saying that this fit function was chosen among others by using a Fisher test. It is a function that describes the background well, period.
L248 source of the systematic uncertainty → remove “the”
L265 “ only the effect .. on signal acceptance” → what does it mean ? that the impact on yield and efficiency was not taken into account ?
Table 2 : In this form, the table is quite confusing. It is not clear if the “magnitude” column is the relative uncertainty on sigma x BR or on the quantity indicated by the last column. In the first case, I would remove the last column. For the label of the second column “Magnitude” is best described as “relative uncertainty” . In the caption: “ the second column, the third column indicates ” → there is an offset in the column count, “Source” is the first column, therefore “Affected quantity” is the fourth, not the third, and “Effect on yield” is the third, not the second.