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--- cms:cms-exo-12-025 [10/04/2014 16:49]
ortona
+++ cms:cms-exo-12-025 [11/04/2014 23:58] (versione attuale)
bellan
@@ Linea 55: / Linea 55: @@
 Line 266-273 Would it be possible to merge these 2 paragraphs? You describe twice how you compute the limits, from 2 different perspectives
+--
+Stefano C.
+- General comments
+) The introduction lacks of details about the models tested: the reader may want to have a bit deeper insight on the production
+mechanisms of this heavy guy, possibly introducing also the rho and pi TC hadrons
+) In general the paper is well written and clear apart from the chapter 4: it has several repetitions and the organization is sub-optimal, especially in the description of the objects (see also text comments). The section on the optimization of M(WZ) and LT cuts has too many details and will probably benefit from a plot with the interpolation of the cuts
+) The Lt variable, used for the optimization of the discrimination against background, does not seem (at least looking at fig. 1)
+to give much more information with respect to the M(WZ) cut. Is it known the improvement in the sensitivity by adding the Lt cuts
+compared to the M(WZ) cut alone?
+) It's not 100% clear to me the assumptions that go into fig. 4 result: is the W'ZW coupling affecting only the BR(W'->WZ)?
+If so, fig. 4 does not add much information to fig. 2 but rather it is the explicit model dependent interpretation of the limits in the EGC model
+- Text comments
+L 86: ".. which produce different physics, but lead to ..." -> "leading to"
+L 101: remove "full"
+L 117: define "standalone muon", which is CMS jargon
+L 127-129: in one line there are 3 "simulated". Consider to use instead "data-to-MC" or some other synonyms
+L 123-124 & 127-128: consider merging these two sentences, since the information is the same
+L 129: You mean "close to unity"? If they were really compatible with unity within the uncertainty it would make no sense to apply them
+L 155: define Delta(pT)
+L 144: "overlapping" -> "additional"
+L 162-163: Clearly this is something that improves the signal efficiency, but what about the overall sensitivity? In principle also the background efficiency improves...
+L 163-164: consider merging this sentence with 127-128
+L 210-211 & 215: is it really needed to explicitely quote the empirical interpolation in the main body?
+L 214: what is a "linear turn-on curve"?
+L 230-241: many repetitions of "we apply"
+Table 1: too many lines and the efficiency does not have units (I assume they are in %)
+L 238-241: These statements sounds obscure to me
+L 246: "same analysis phase space" -> "same phase space of the analysis" ?
+--------------
+--
+Riccardo
+*General comments*
+The paper in general is well written, however there are some places where some slang is used. The most relevant is the assumption "lepton = charged lepton". For example, the title should be changed to read "Search for new resonances decaying to WZ using leptonic channel in pp collisions at sqrt(s) = 8 TeV", or something similar, but not "trilepton", as the neutrino is also a lepton.
+I propose to change make this change everywhere in the text.
+*Specific comments*
+Biggest comment:
+To reconstruct the W you use the standard technique that foreseen to constrain the neutrino-charged lepton invariant mass to the nominal W mass, to extract the neutrino pZ. This method clearly, cannot precisely reconstruct the W (either because of the gamma_W and  of the W boost, as you state in the text). Now, the net result is that M(ZW) reconstructed like that is not exactly M(WZ) and therefore it is not exactly M(W'). I do not see cited anywhere the systematics associated to this approximation and I expect that it directly impacts the limit on W' as it is an indetermination on the energy scale extracted from the approximated M(WZ). Can you clarify if you have included this systematics in the analysis and if so eventually state that more clearly in the text?
+Abstract
+First sentence: I would add after muons  "[...] and a neutrino."
+Text
+L19: instead of trileptons, use leptonic
+L23: three leptons --> three charged leptons
+L25: top pair --> top quark pair
+L31: you wrote "low ZZ production" but it is not clear compared to what. Is it w.r.t. typical signal cross sections? If so, add few words.
+L34: the search --> the 8 TeV data analysis
+L35-L40: Not very clear. I do not understand if the drop in the efficiency due to the isolation requirement was already present in 7 TeV or not, or if the isolation used for 7 TeV analysis cannot be used for 8 TeV because it is inefficient for the more boosted Z than in 7 TeV. I strongly suggest to rephrase it to make clear what is happening.
+L76-L78: "We consider [...] 25 GeV" --> "We consider the relationship between rhoTC and piTC M(piTC) = ... [18,31],",  i.e, I suggest to drop the part on Les Houches and just put the citation after the formula.
+L83: "The background processes" --> "The processes to estimate the background"
+L96: Object --> Particle
+L106-107: I suggest to move the latter sentence later, after the trigger description, i.e., after L122.
+L115: instead of quotes I prefer italic style, as quotes in general give the impression it is not a precise word, while here is more an alias, so better to use the italic.
+L122: "[...] tracker muon [36]." --> "[...] tracker muon. A more detailed description of the muon identification algorithm can be found elsewhere [36]." OR rearrange such a way that ref 36 will refer to the muon id in general and not only to the tracker muons only.
+L127-L129: Why you apply a correction if it is compatible with unity?
+L139-L143: particle-flow isolation is jargon. I suggest to rewrite such that it looks like:
+"Electron candidates are also required to be isolated: the sum of the transverse momenta of all neutral and charged reconstructed
+particle candidates inside a cone around the electron in eta-phi space of DR < 0.3 is divided by the pT of the electron and is requested to be less than 0.15.
+The isolation computation also includes ..."
+I find the section on muon reconstruction a bit not precise. I have therefore some corrections:
+L150-L151: This sentence is wrong. Remove Global in front of muon and '("tracker muons")' too.
+L152: "in the global muon track fit" --> "in the combined muon-tracker hit fit"
+L157: "Particle-flow-based relative isolation [...] 0.12." --> "Particle-based relative isolation, defined as the sum of the transverse momenta of all neutral and charged reconstructed
+particle in a cone size of DR < 0.4, is required to be less than 0.12."
+L159: "The above [...] Z decay" --> "The identification requirement for muons coming from a Z decay are relaxed with respect to the one from W, for which instead we use the above criteria."
+L159: pileup --> pile-up
+L159-L161:
+"One of the leptons is allowed to be a tracker muon instead of a global muon and the requirement on the number of muon chamber hits is removed" --> "One of the muon is allowed to be a tracker muon only and the requirement on the number of muon chamber hits is removed."
+L161-L162: not clear if the lepton removal is only for the muons from Z or for all muons. If it is only for muons from Z, then why? If it is for all muons, then the sentence, in that position, make that not clear (in this latter case you should move this sentence after pile-up in L159).
+L174: not clear at all what you mean with "non-overlapping Z boson".
+L177: "A lepton" --> "A charged lepton" and I must admit that I do not like the "W lepton" alias, better use "W charged lepton".
+L196-L201: See the "biggest comment" mentioned above.
+L204-L218: This is a key point of the analysis and I think this piece of text does not make the job to explain well what we do. It is not clear what is the 100 GeV mass spacing, as then in Tab 1 there are no quantities varying by 100 GeV steps. Then it is not clear what is parametrized as a function of M(WZ), L_T and M(WZ)??? Clearly the latter is not, but what is then the second term? A window on M(WZ)? Make it clear.
+I think also the part from L209 to L218 is particularly hard to be followed, why not having plots that help to explain that part?
+Without some rephrasing in this paragraph, I am afraid, an external reader will drop reading further.
+Figure 1. Last sentence of the caption is not true for the plot on the left. Please adjust the sentence to refer only to the plot on the right.
+L275-L276: Remove "The largest [...] (see Table 1)." There is no need to draw attention to a fluctuation.