General Comments:
We have not yet submitted the full reading of the note to each member of LOUVAIN since we believed that it first needs to be significantly improved prior publication. - What's the main improvement and/or additional message with respect to CMS note ref. [5]? The present note should maybe be presented has a continuation and a complementary work? In its present form, the note looks more like an internal technical note than a public CMS note. - We believe the sections describing the tools should be strongly reduced. Especially since it lacks figures and illustrations... making the reading rather difficult to digest. We try to illustrate this point with the more detailed comments below. - Section 3.1 is very difficult to read. It contains a lot of slang words and definitions are missing. In addition, this section also contains four series of itemization and one long sub-itemization, showing an obvious problem of structure. - We suggest to maybe merge section 3.1 and 4 since section 4 defines notions used in 3.2. (and in this context, section 4 could also be further reduced). - Generally speaking, footnotes are to be avoided, according to the author guidelines. - Our understanding is that for this series of papers the detector will be described in a general introduction. Most of the introduction, and the first paragraph of section 2 are therefore unnecessary.

Detailed comments:
2 : general purpose -> "general-purpose" or « multi-purpose » 5 : delete the sentence "These broad... ...Standard Model.", and merge the next paragraph to the first one 8 : Strange sentence... I would not start with "the responsibility ... " 17: ? what's the fraction of cosmic muons in the 270 million cosmic ray triggered events? 35 : « In addition to the above » delete and start with The CMS 37 : « at the full bunch crossing rate » -> "at a bunch crossing rate" 44 : « 200-300 Hz » ref [5] and prior work mention 100 Hz. Precise why/how it changed. 53: it contains undefined jargon (regional data unpacking, seeds) and is not really needed. Section 3 70 : Title of section 3: "HLT During CRAFT" rather vague...


76 : " L1 pass-through triggers" slang and actually not defined... unless sentence at line 74 is modified 77-80 : Sentences are rather vague... either cancel or be more precise. we are not sure to understand but we would add sth like: ... to select events in nominal conditions. Or "that will be used to select physics events during beam collisions. 84 : " L1 trigger objects" slang... also introduced L1 bit at line 75.... should either be "L1 object" or "L1 trigger object" in contrast to "L1 trigger bit"... or is it the same thing? Later on, at line 87, you talk about "L1 single-object algorithm triggers"... later you talk about "generic trigger", and later, "generic physics event label"... 85: What is the difference between algorithm and technical triggers, for what concerns the HLT? 86 : Sentence starting at "During CRAFT..." is too long. 89-90: ? You mentioned at line 73 that L1 undergone extensive commissioning but here, you mention that there was a L1 commissioning effort... isn't there a contradiction? 91 : delete "were masked by the GT and" ... slangy and redundant with the next part of the sentence... also Repetition of the end of previous paragraph. 92: ... by L1 would however include the results... 96-97: and Bad hyphenation 98-99: "All triggers process every event accepted by L1". Does that mean there is no L1 seed required for CRAFT08 triggers? Please clarify. Besides, this second sentence is obviously redundant and/or trivial 100-115: That paragraph is a bit difficult to follow, with discussion of some L1 aspects mixed with the HLT discussion. By the way, "GT" or "global GT" both are written... 107 "the LHC bunch structure was emulated by CMS during CRAFT..." Too long an explanation to fit within an itemized paragraph. 111 Confusing paragraph to just say that in the case of random trigger, a prescale is being applied in the HLT. 113: for CRAFT08, I think "limited to few Hz" is more adequate. 133: If we do a rough estimate: rate in pixel ~0.1Hz, so P(coincidence)~1E-8 @ 1Hz, ~1E-6 @ 100Hz. Therefore, one expects one pixel event in the random sample every ~1E4s !!! It might be the same for HF, but there we don't have numbers. So, that trigger is useless as a backup. 162: How is the transverse energy defined for cosmics. From the transverse components of P? Using the crystal position + IP hypothesis (beam line)? It's worth clarifying as transverse quantities are used also later on.


157: ...background studies for example for HSCP. section 3.2: 182: Why not something like "Online Deployment of HLT conditions and rules? (Menu is maybe ambiguous or slang). by the way, what is the difference between the title 3.1 and the title of the entire section "HLT during CRAFT"? Again the structure is unclear... 187: (then 350 and 353): avoid footnotes. 192: "validation farm" what does that mean? try to unify your convention naming 195: "to collect (event) data from" why event in parenthesis? event data or/and "non-event data should be better defined. 195 : the sentence "The first ... processing" might be unclear for people not involved in the CMS data operation. For instance " How does one collect data from a process? what is a process, a Filter Unit process? 207 : How can the rejection power be tested on already selected events? Are you using some zero-bias sample, which is not mentioned? Section 4: 208 : "streams" and "primary datasets" are jargon not introduced before section four. The size of this section could also be reduced and re-organized. First a long introduction is given with short subsections (4.1 for instance). Second, there are repetitions and inconsistency naming between streams defined in the itemized part in introduction and the subsection 4.1 and 4.2. Third, there are sentences and paragraphs with slang words and structure such that they are very difficult to read. 233: What is a "reduced event data" ? We suppose this is an event containing a reduced amount of information. Why not call it this way. If reduced data is to be used often in the paper, then clear definition should be given. 235: what do you mean by "homogenous information" 235: The event content used for physics stream comprises the full detector ... --> The event information written in the physics stream includes... 242: Items: we would give less details since most of them are introduced again in subsections 4.1 and 4.2. Why the calibration and physics stream do not deserve dedicated subsections? 251: "For example, ..." We do not understand this sentence... 267: title: why has this stream a double naming? We would call it DQM stream and, as said, this stream includes HLT by-products (to be defined as well...). 276: "directly off it" ?


284: what is a " reconstruction-level objects" ? purely CMS slang 281: you introduce "reduced event content" and then on line 286 "small portion of the event data" do you talk about the same reduction here? if yes, use the same English words to name it. By the way, 281 and 286 information is almost identical... 297: "PDG Pi0 mass" --> "Pi0 mass" simply... PDG not defined and here, it is irrelevant anyway... Section 5: We understand that section 5 is the main actual results (and not a description) motivating this publication. It could therefore be extended and content maybe more actual results. 322 referring to a specific sub section as an introductory paragraph is not correct. Here, you should give general words on the section or list the actual message of each sub-section. 368 avoid HLT_L1MuOpen especially since it is even not what is in the axis of Fig. 1 and also because it is actually not used later in the paper. 383 : "... offline DQM are: all reconstruct ...; and..." we would avoid : and ; and cut the whole sentence into two. Figure 2: Redo the figure with TDR style and higher quality. Then, what is the feature around eta=0? 415: "especially for L1 trigger performances"... is this part of the sentence really relevant in a HLT paper? 423: idem: "...studies of level-one and...". This is not a L1 paper. 452: Which one? Be a bit more precise, maybe. 461: could this be monitored in the FU by online DQM? We hope this helps, best, Christophe Delaere and Vincent Lemaitre, for the LOUVAIN group christohe.delaere@cern.ch vincent.lemaitre@uclouvain.be