Responses to the first round of comments to Texas A&M. This set of comments was sent in two parts. Answers begin with a **. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Date: Thu, 23 Oct 1997 8:40:49 -0500 (CDT) From: KAMON@FNALD.FNAL.GOV To: toback@fnald.FNAL.GOV, FRISCH@uccdfj.UCHICAGO.EDU CC: chertok@cdfsga.fnal.gov, Kamon@HEPRB.tamu.edu, KAMON@FNALD.FNAL.GOV Message-Id: <971023084049.2c802214@FNALD.FNAL.GOV> Subject: 1st comment on diphoton PRL paper David I made a quick check of youre draft PRL paper and have several editorial comments/questions. I will send them later.. For a quick correction for theoretical view point: Ref. 1f is not gauge-mediated model. That (LNZ model) is constructed within their supergravity scenario. Thus, you need to have a minor correction on that wording of the text. Also: they (LNZ) has a published paper on the CDF eegg+MET event to constrain their scinario in PRD 55, 4450 (1997). I would suggest to add this in Ref.1f. Just as an example of referring to the LNZ model and gauge-mediate model in a LEP paper: ------------- Paper: hep-ex/9710009 From: "DANN James PPE U. santa Cruz" Date: Fri, 10 Oct 1997 14:14:58 GMT (66kb) Title: Searches for Supersymmetry in the photon(s) plus missing energy channels at $\sqrt{s}$ = 161 GeV and 172 GeV Author: ALEPH Collaboration Comments: Latex, 15 pages with 7 eps figures Report-no: CERN-PPE/97-122 \\ Searches for supersymmetric particles in channels with one or more photons and missing energy have been performed with data collected by the ALEPH detector at LEP. The data consist of 11.1 pb-1 at $\sqrt{s} = 161 GeV$, 1.1 pb-1 at 170 GeV and 9.5 pb-1 at 172 GeV. The e+e- -> nunu+photon cross section is measured. The data are in good agreement with predictions based on the Standard Model, and are used to set upper limits on the cross sections for anomalous photon production. These limits are compared to two different SUSY models and used to set limits on the neutralino mass. A limit of 71 GeV/c^2 at 95% C.L. is set on the mass of the lightest neutralino ($\tau_{\chi_{1}^{0}} \leq $ 3 ns) for the gauge-mediated supersymmetry breaking and LNZ models. \\ ( http://xxx.lanl.gov/abs/hep-ex/9710009 , 66kb) ** You are quite correct this model is not a gauge-mediated model. The text has been changed to reflect this. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ----------------- From: SMTP%"chertok@cdfsga.fnal.gov" 8-NOV-1997 15:31:54.32 To: TOBACK CC: Subj: Comments on CDF4149 (diphoton PRL) Date: Sat, 8 Nov 1997 15:32:05 -0600 (CST) From: Maxwell Chertok To: toback@uccdf.uchicago.edu cc: Teruki Kamon , "James P. Done" Subject: Comments on CDF4149 (diphoton PRL) Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Dear David We summarize our group's comments on "diphoton" paper (V2.0): (1) Ref. 1f: This is a sugra model, and different from gauge-mediate models. Thus, the last line of P.8 has to be modified. Also: please add PR D55, 4450 (1997) in Ref.1f Lopez et al examined their model in the paper. Note: this is the same as Teruki sent several days ago. we just included just for a completeness. ** You are quite correct this model is not a gauge-mediated model. The text has been changed to reflect this. (2) Refs. 2 and 11: add "Proceedings of .." ** This has been fixed (3) Some modification to clarify the contents: P.5 Line 5: the high-threshold (16 GeV) trigger .. ^ single photon ** No. This is not a single photon trigger. This is a diphoton trigger. The triggers are TWO_CEM_16 and PHOB_DIPHO_16 P.5 Bottom line: .., where \sum Et does not include ... ^ is the scalar sum of Et over all calorimeter towers (\eta < 3.6 ??) ** Yes this is the standard SUMET. P.8 Line 16 from bottom: 3 x 10^12 ... We thought 20 pb-1 <--> 1 x 10^12 collisions, thus 85 pb-1 <--> 4 x 10^12... ** You are correct. There were roughly 4E12 collisions. However, there were multiple collisions per bunch crossing. Since we look at bunch crossings (what we usually call events) for multiple collisions, we count the number of bunch crossings to be consistent (and conservative). This is discussed in CDF Note 3892. P.8 Line 12 from bottom: wach of W's .. ~~~ in Italic.. ** Done (4) Table I If we compare the text (P.6) and Table I, we find: Et(gam) > 15 Et(gam) > 25 MET > 35 1 (0.5+-0.1) --- N(j)>= 4 2 (1.6+-0.4) --- MET > 25 --- 2 (0.5+-0.1) N(j)>= 4 --- 0 (1.7+-1.5) <=== (a) ------------------------------------------------------ b-tag 2 (1.3+-0.7) extra lepton(s) <=== (b) mumu 1 (Z-->mumu+gamgam) ee 1 (Z-->ee+gam) tau 1 (0.2+-0.1) Et(gam_3)> 25 0 (0.1+-0.1) Questions (a) In Table I, there is no categoly of N(j) >=3 for Et(gam) > 25 GeV, while you listed 0 events for "central gamma, Et(gamma_3) >25". (b) In the text, you said 4 events with additional lepton(s). But, you explained for 3 events and listed 3 events in Table II. 4 or 3 events ? ** This is a long comment. (a) For space reasons we have not included the counting experiment results for events with photon Et>25 GeV. The result is in the text as you point out. The "central gamma, Et(gamma_3) >25" is not three photons above 25 GeV. If there were an event which had two photons (passing the cuts) with Et>12 AND a third photon with Et>25 then this would have been counted. No such events were seen. We have not mixed thresholds. Also, your rendition of our table is not correct. You missed the eeggmet event. The table lists three events with a central e or mu, and one event with a central tau. (5) Table II We remember the mass of gamma_1 and e- was around the Z mass. If a referee pointed out, how would you address on a possibility of Z + X... ** You (and they) would be quite correct. This could be a Z with a lost track. The probability of this is small (~2% as estimated in CDF Note 4183, P29). It doesn't make the event any more understandable. The plug cluster and Met still wouldn't really have an explanation. We have estimated this type of source in CDF Note 3892 section 6, see Table 6. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ And a few more comments: (6) p.4 and elsewhere. We think that the Greek versions for N_1 and C_1, (N_2, etc.) using the Chi symbol, tilde, etc., are standard. Could you double check? ** We argued about this in the GPS meetings. The papers we set limits on (Ambrosanio et al, and Babu et al,) both use the N1 and C1 notations. We decided to use what was in those papers. (7) p.4 middle of 1st paragraph. You don't need to define MET again here. ** You are quite correct. Done. (8) p.5 paragraph 3. From your description, the reason and method for determining isolation photon ID efficiency using Z0 decays is not clear. ** This is the standard method used to estimate efficiencies used in the R analysis. There is simply not enough space into a more complete description. A more complete description will be done in the PRD. (9) p.5 paragraph 3. How about "Since the purity of the sample ... signatures than IS the efficiency..." ? ** We disagree. The text is clear, and this is a purely stylistic comment. If you feel strongly, we can get an arbiter. (10) p.5 end of paragraph 3. Do you want to say a few words as to how you measure the fraction that contains 2 prompt gammas? ** We've already talked about the method as well as given reference to standard method of estimating the purity in the middle of the paragraph. Just so you know this has been done by the photon group for years and is used, for example, in the diphoton cross section measurement. There simply isn't enough space to add more to the text. It will be discussed more in the PRD. (11) p.5 last paragraph. How about $\met^{x,y}$ instead of $\met^{x}$ ? ** I think that would be confusing. Besides, the measurement was done with just X. (12) p.6 and elsewhere. $b$ for b quarks (you use it in some places) ** You are quite correct. This has been fixed. (13) p.6 first paragraph. You say that jet ID is not affected by MET mismeasurement, so you don't require the dPhi(MET,jet) selection. But that contradicts what you say at p.5 last paragraph. ** Hmmm...Just because the jets affect the met, doesn't mean that the met affects the jets. I agree that sample with large met probably have mis-measured jets, however, the most unbiased thing we can do is to NOT cut on anything which could cause a bias. (14) p.6 2nd paragraph. We think you should redefine "expected" as expected from SM processes. ** A reasonable request, but it makes the paragraph read funny. Its a stylistic point so we left it as is, especially, since we're over length. (15) p.7 1st sentence of text: "pass" instead of passes (if that is in fact what you mean!) ** We disagree. If you feel strongly, we can get an arbiter. (16) p.8 2nd to last sentence in paragraph 1 is awkward as written. ** That has been fixed.