Dear Florencia et al, please find below my comments on the Jet Energy Scale NIM article. Congratulations to everybody involved writing this up. It is a very nice paper and worth all the effort that went into writing it. I hope my comments are helpful to further improve the paper. I consider requesting my name to be added to the paper since I originally coordinated the first calorimeter tuning when I was in charge of simulation. This activity then turned into the Calorimeter Simulation Task Force where my postdoc Soon Jun played a major role. He should also be an author of the paper. I also like to request my student Vivek Tiwari to be an author based on more than 2 years of work on the ADMEM's (Larry actually suggested to add Vivek). With the same argument, Mark Mattson, the other ADMEM pager carrier, should be an author (but it is not up to me to request this). Thanks, Manfred. ------------------------------ Here are my comment on CDF 7543, dated July 11, 2005. I hope they are useful in some way: * General Comments: ^^^^^^^^^^^^^^^^^^^ - Some of my comments below are English comments; since I am not a native speaker, please take them as suggestions and check with a native speaker. - I don't know whether this is still possible, but it would be great if we can give some of the plot a more professional appearance, such as Figs. 2, 7, 17, 18, 33, 34, 35, 36. No grid in figures! - I don't need to mention that we need real references for many of the references * Specific comments: ^^^^^^^^^^^^^^^^^^^^ * page 1: - abstract: ... clusters of energy deposited in the calorimeter. A detailed understanding of the calorimeter calibrations and simulation is required. * page 5: - l. 13: correcting the jet - l. 20 & 27: it would be good to spell out that the subscripts MI, UE and OOC stand for multiple interaction, underlying event and out-of-cone, respectively. * page 6: - l. 9: if you give numbers 0.4, 0.7 and 1.0 characterizing the cone sizes, you need to define that you are talking about a cone of size dR = sqrt(...). I would just say: "Different cone sizes are studied and all corrections are derived for the specific cone size." (that's good enough for this overview in the introduction) - l. 20: to go from single particle response to comparing jets, you also need to make sure your MC generator gives the right track multiplicities and charged/neutral fractions in your jet. You would never be able to compare jets if your MC generator generated only jets with 3 tracks every time. I think it should be mentioned that Pythia and Herwig do a good job with respect to this. * page 8: - l. 10: remove (COT); it is also defined in l. 14 which is the right place - l. 11-13: mention that SVX is double sided silicon - l. 16: divided into eight superlayers of 12 ... - l. 22: It is described in - l. 28: are used for photon ... * page 9: - l. 2: and the forward calorimeter at * page 10: - we've put the essential information about the CDF calorimeters such as range, resolutions, thickness, etc in form of 2 tables (Tab. 3.2 & 3.3) in the detector description of the B Physics in Run II yellow book (page 102/3). I would recommend using a table instead of putting everything into text as you do at the top half of page 10. I'm sure I still have the LaTeX of those tables and could send to you if you like it. - we should quote references for the various sigma(E)/E resolutions given - l. 8: |eta| < 3.6, and are based on the same - l. 19: do we want to describe the ADMEM? - l. 25: what does 'well identified' mean? Define! - l. 33: add blank: test beam [16, ...] - l. 34: does not interact in the CEM - l. 38: explain what you mean with 'in situ muon data'; how were the muon data used? * page 11: - l. 8: Their online response is kept ... - l. 9: are used to obtain this ... * page 12: - l. 7: calibrations - l. 9: run number. This - l. 14: From Fig. 3 and 4 we derive an uncertainty on ... of the CEM of about 0.3% and for the CHA of 1.5%. - l. 15: insert blank: 70% of - l. 16: CHA, the corresponding uncertainty is thus 0.5%. * page 13: - l. 2: number. the --> number. The - l. 3: probes --> probe - l. 4: and the most inner part --> plus the inner most part * page 14: - l. 5: phi^tower - phi^jet - l. 12: from the origin of the CDF detector to the center - l. 25: overlaps in more than 50%. --> Explain 50% of what? * page 15: - l. 6: sqrt{Px,jet2 + Py,jet2} <-- Py - l. 14: I would call this section 'Particle Jets in Monte Carlo' * page 16: - l. 18: (see Section 5). - l. 19: quote a reference for XFT - l. 35: of the electrons to be 76 < ... * page 17: - l. 2: with an muon transverse - l. 4: requiring two muons with - l. 5: muons to be 75 < ... - l. 8: threshold of 2 GeV for each electron. - l. 10: 1.5 GeV/c for each muon. - l. 13: the word 'used' is used way too often here: I suggest: [22] are utilized. - l. 15: MC samples were generated. - l. 18: put blanks between 0, 10, 18, 40, ... - l. 21: yes, specify the correct range - l. 23: word data used too often: use '... and Single Track triggers.' - l. 29: first, why did we use BGEN and not Pythia for the J/Psi MC? We should explain that BGEN does not give a complete event with fragmentation and underlying event. In addition, BGEN does not give you prompt J/Psi which is the majority of the J/Psi in the data * page 18: - l. 3: For Pythia a so-called "Tune A" version [25] ... - l. 10: in Section 3. <-- add . * page 19: - you describe the hadron tuning first and then the em tuning; historically it was done the other way around. I guess it doesn't matter in which order the tuning is described - l. 22: in detail in Ref. [29] and ... - l. 26: energy deposited (E_dp) by a ... * page 20: - l. 1: fractions - no v - l. 10: by choosing a correlated (alpha_i,beta_i) pair at random. - l. 15: in Eq. (14) and ... - l. 16: three contributions normalized such - l. 19/20: when a pi0 is produced in the first inelastic interaction. It also scales ... - l. 21: hadronic showering - no i - l. 25: are correlated through: * page 21: - l. 12: remove line with Eq. (20) by taking out \\ at the end of line 11 - l. 21: the calorimeter as one effective ... in three dimensions <-- s - l. 22: The deposited energy ... based on the CDF calorimeter ... - l. 30: from the H1 collaboration [29]. * page 22: - l. 5: trigger data with track momentum 3 < p ... and test beam data with 7 < p < ... - l. 7: by the central calorimeters, CDF - l. 12/13: tracks are selected and extrapolated to the surface of the calorimeter taking the magnetic field into account. - l. 15: not within the inner 81% of the tower surface are not considered. - l. 23: no tracks extrapolate within a - l. 25: within the 7x7 blocks - l. 34/35: necessary since no other particles were generated in the event. * page 23: - l. 1: Because of the limited statistics of the single track trigger data, the in situ ... possible for track momenta ... - l. 4: I think it would be good to explain that refers to the average E/p (not sure whether this is the first time this symbol is used here or already earlier). - l. 13/14: test beam data taking in the momentum range 7-227 GeV/c are used for ... * page 24: - footnote: response for non-interacting * page 25: - I think Soon should be able to beautify Fig. 7. I'll ask him. - Fig. 7, l. 1: observed in CHA for particles - Fig. 7, l. 3: are compared to the - l. 5: Note, that in the test beam ... of the tower while for - l. 6: in situ data the track extrapolating to the inner 81% of the tower are used. * page 26: - Fig. 8, l. 5: test beam data we assigned an error of - l. 3: However, in each case the results are consistent - I would put the info from the footnote into the main text. * page 27: - l. 10: central region where - l. 10/11: In addition, since the tracking efficiency is very low in the very forward region |eta|>2.8, other methods ... - l. 21: take out 'in the plug calorimeter' - it is redundant; this section is about plug - l. 24: made <-- no q - 5.3: as mentioned above, the em tuning was historically done first for the central; I think for the plug it was done in parallel with the had tuning; logically this makes more sense to me and I would have first talked about the em tuning in the NIM paper and then described the had tuning - l. 32: to study data and MC. * page 28: - Fig. 9: observed in the plug calorimeter ... (Open circles). <-- . missing - l. 5: where do you get this1% accuracy from? Explain. * page 29: - Fig. 10: (closed squares) ... (open squares) <-- there are no circles in the figure * page 30: - l. 8: when more single track trigger data - l. 18/19: as a function of .... between 3 and 5 GeV/c for all towers combined. * page 31: - Fig. 12, l. 1: Difference between of data - Fig. 12, l. 5: data are statistical. For the test beam data we assigned an error - l. 4: Difference in between data - l. 7/8: which implies x_CES < 21 cm. (Explain why this implies 21 cm). - l. 8: remaining 16% are studied - l. 9: explain what you mean with 'standard criteria' or give a reference - l. 13: within 10 GeV/c2 of the Z boson mass. - l. 14:For these track based electron candidates, is shown in Fig. 15 as a function - l. 16: and simulation in for Z -> e+e- events as a function of * page 32: - Fig. 13: between 12 and 16 GeV/c (right). - l. 6: it is 1.7% constant for all momenta. * page 33: - Fig. 14: for electrons from J/Psi -> e+e- - I assume the data in the plots here are sideband subtracted. This is certainly important for the J/Psi -> ee. This could be mentioned in the text. - Fig. 15 and 16 should be combined to 1 Figure; Fig. 16 at the bottom, and the caption modified accordingly. Also, the data-MC comparison does not look so great. Can we do better? * page 35: - l. 7: The relative corrections include a contribution for the transverse spreading of calorimeters showers <-- s - l. 12: We call this procedure the - l. 20: and probe jet <--no v - l. 21: can be inferred through - l. 26: we could show examples of both distributions pT^probe/pT^trigger and Eq.(22) as illustration of the argument of being a Gaussian distribution * page 36: - l. 1: is present in the event the pT ... less than 7 GeV/c for - l. 2: 8 GeV/c - l. 3: 10 GeV/c - l. 5: than the trigger threshold of the respective dijet sample. - Sec 6.2: Should we also show the results for cone sizes of 0.7 and 1.0? - l. 12: for data and PYTHIA MC samples for a cone size of dR = 0.4. - l. 15: in the region 0.2<|eta|<0.6 for both - l. 17: gap between calorimeters - l. 25: by th lines linearly interpolating between the measurement points in Fig. 17. - l. 32: a pT^jet dependence. These uncertainties will be ... of the systematic errors. * page 37: - l. 3: event selection requirements and That's it for now. I will try to read Sec. 7-12 before the deadline but wanted to send you already the comments above. Best, Manfred.