------------------------------------------------------------------- From womersley@fnal.gov Wed Jun 20 12:11:33 2001 Return-Path: Received: from fnal.gov (heffalump.fnal.gov [131.225.9.20]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5KHBX024806 for ; Wed, 20 Jun 2001 12:11:33 -0500 Received: from fnal.gov ([131.225.225.124]) by smtp.fnal.gov (PMDF V6.0-24 #37519) with ESMTP id <0GF800175NR8NZ@smtp.fnal.gov> for strauss@mail.nhn.ou.edu; Wed, 20 Jun 2001 12:11:33 -0500 (CDT) Date: Wed, 20 Jun 2001 12:02:31 -0500 From: John Womersley Subject: 630/1800 photons To: strauss , "marek@fnal.gov" , Daniel Elvira Message-id: <3B30D727.CA226691@fnal.gov> Organization: Fermi National Accelerator Laboratory MIME-version: 1.0 X-Mailer: Mozilla 4.74 [en] (WinNT; U) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Accept-Language: en Content-Length: 830 Status: RO Mike, congratulations, this looks very good. I have only a few small comments. 1. I would suggest adding a mention of the low ET behavior in the abstract, given the focus that this has had over the years. for example "...show satisfactory agreement in most of the ET range. While the measured cross section at 630 GeV exceeds the prediction at low ET, this excess is of marginal statistical significance." 2. measurement is mis-spelled in first sentence of para 5. 3. The paper does not make clear whether it is Owens' or Vogelsang's calculations that are used in the figures and tables. Some statement about how well the two calculations agree would also be useful. We should try to keep on good terms with both guys and give them equal billing as far as we can. John ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Wed Jun 20 16:00:11 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5KL08026506; Wed, 20 Jun 2001 16:00:08 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f5KL08726221; Wed, 20 Jun 2001 16:00:08 -0500 (CDT) Date: Wed, 20 Jun 2001 16:00:08 -0500 (CDT) From: Mike Strauss Message-Id: <200106202100.f5KL08726221@particle.nhn.ou.edu> To: womersley@fnal.gov Subject: Re: 630/1800 photons Cc: strauss@mail.nhn.ou.edu, marek@fnal.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: rVnrx6rzRXPu79IIcVoCJg== Content-Length: 2640 Status: RO John, Thanks for your comments. My responses are written below. > congratulations, this looks very good. I have only a few small > comments. > > 1. I would suggest adding a mention of the low ET behavior in the > abstract, given the focus that this has had over the years. > > for example "...show satisfactory agreement in most > of the ET range. While the measured cross section at 630 GeV > exceeds the prediction at low ET, this excess is of marginal > statistical significance." I will add this. > 2. measurement is mis-spelled in first sentence of para 5. I will fix this. > 3. The paper does not make clear whether it is Owens' or Vogelsang's > calculations that are used in the figures and tables. Some > statement > about how well the two calculations agree would also be useful. > We should try to keep on good terms with both guys and give them > equal billing as far as we can. I would like to discuss this. It is exactly because of "equal billing" that I didn't mention whose I used. Jeff and Werner worked together to make sure they were doing things in the same way and that their CTEQ5M numbers agreed (at least to the extent that they understood the difference.) In the CC, Werner's numbers are a little higher over most of the E_T region than Jeff's because of the way they handle NLO fragmentation. At 10 GeV Werner is about 10% higher than Jeff. At 40 GeV, about 5% higher, and at 70 GeV, about the same. In the EC, Werner's numbers are about 20% higher over most of the E_T region. I used Werner's numbers for two reasons: 1) His cross section is much smoother. The errors on Jeff's are much larger, and his cross section values must be smoothed to give a nice smooth curve. (Steve Linn smoothed Jeffs in the 1A-1B paper). 2) Werner actually calculated the cross section in the nonuniform bins I used to calculate x_T, thus giving me an exact theoretical cross section using the same bins I have used. In the acknowledgements, I acknowledge both, and in the paper I say that the theory is CTEQ5M. Both statements are true. I chose not to say whose theory is actually plotted since they both worked hard on the theory to make sure the numbers I used were accurate. I don't know if we should do anything else. I think drawing both curves would distract from the paper. We are not trying to differentiate between two theorists using the exact same theory. We could state in a footnote that the calculations agree to witin 10% at low E_T and are the same at high E_T, but I'm not even sure that is necessary. Any thoughts? -Mike ------------------------------------------------------------------- From marek@d0mino.fnal.gov Wed Jun 20 17:40:05 2001 Return-Path: Received: from d0mino.fnal.gov (d0mino.fnal.gov [131.225.224.45]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5KMe4023964 for ; Wed, 20 Jun 2001 17:40:05 -0500 Received: from localhost (marek@localhost) by d0mino.fnal.gov (SGI-8.9.3/8.9.3) with SMTP id RAA44777; Wed, 20 Jun 2001 17:40:04 -0500 (CDT) Message-Id: <200106202240.RAA44777@d0mino.fnal.gov> X-Authentication-Warning: d0mino.fnal.gov: marek@localhost didn't use HELO protocol X-Mailer: exmh version 2.0.2 2/24/98 To: Mike Strauss cc: womersley@fnal.gov, marek@fnal.gov Subject: Re: 630/1800 photons In-reply-to: Your message of "Wed, 20 Jun 2001 16:00:08 CDT." <200106202100.f5KL08726221@particle.nhn.ou.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 20 Jun 2001 17:40:04 CDT From: Marek Zielinski Content-Length: 3186 Status: RO Mike, I asked before the same question about which theory we use, but did not understand how much they are different. Others may also wonder. The minimal solution could be adding "(Vogelsang)" in the captions. I do not insist on making statements how the two calculations compare; if we do not specify Vogelsang in the discussion in main text, this to me implies that the conclusions hold for both. Comments? Marek ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Wed Jun 20 17:49:04 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5KMlm021286; Wed, 20 Jun 2001 17:47:48 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f5KMlmi26354; Wed, 20 Jun 2001 17:47:48 -0500 (CDT) Date: Wed, 20 Jun 2001 17:47:48 -0500 (CDT) From: Mike Strauss Message-Id: <200106202247.f5KMlmi26354@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, marek@d0mino.fnal.gov Subject: Re: 630/1800 photons Cc: womersley@fnal.gov, marek@fnal.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: 7bpbiepgdPO0H20WAxHmZA== Content-Length: 3533 Status: RO If we do mention Vogelsang, then I feel that we may be in danger of alienating Owens since my choice of Vogelsang is somewhat arbitrary and they both did a lot of work on the theory. -Mike ------------------------------------------------------------------- From womersley@fnal.gov Wed Jun 20 17:50:26 2001 Return-Path: Received: from fnal.gov (heffalump.fnal.gov [131.225.9.20]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5KMoQ023376 for ; Wed, 20 Jun 2001 17:50:26 -0500 Received: from fnal.gov ([131.225.225.124]) by smtp.fnal.gov (PMDF V6.0-24 #37519) with ESMTP id <0GF900M9N3G24R@smtp.fnal.gov> for strauss@mail.nhn.ou.edu; Wed, 20 Jun 2001 17:50:26 -0500 (CDT) Date: Wed, 20 Jun 2001 17:41:23 -0500 From: John Womersley Subject: Re: 630/1800 photons To: Mike Strauss Cc: marek@fnal.gov Message-id: <3B312693.9C125756@fnal.gov> Organization: Fermi National Accelerator Laboratory MIME-version: 1.0 X-Mailer: Mozilla 4.74 [en] (WinNT; U) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Accept-Language: en References: <200106202100.f5KL08726221@particle.nhn.ou.edu> Content-Length: 3223 Status: RO Mike, OK, this is good. Leave everything as is but I would suggest combining [11] and [12] in a single reference with a note which would read (for example) [11] H. Baer, J. Ohnemus and J.F. Owens, blah; W. Vogelsang, blah blah. The authors of these predictions have verified that their calculated cross sections are consistent over the whole range of photon transverse energies measured here. JW ------------------------------------------------------------------- From RJMadaras@lbl.gov Fri Jun 22 14:28:07 2001 Return-Path: Received: from postal2.lbl.gov (postal2.lbl.gov [131.243.248.26]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5MJS6P23528 for ; Fri, 22 Jun 2001 14:28:06 -0500 Received: from SpamWall.lbl.gov (localhost [127.0.0.1]) by postal2.lbl.gov (8.11.2/8.11.2) with ESMTP id f5MJS5205536 for ; Fri, 22 Jun 2001 12:28:05 -0700 (PDT) Received: from lbl.gov (dplbl1.fnal.gov [131.225.226.122]) by SpamWall.lbl.gov (8.11.2/8.11.2) with ESMTP id f5MJRx605532; Fri, 22 Jun 2001 12:27:59 -0700 (PDT) Message-ID: <3B33BC69.77CBF7F3@lbl.gov> Date: Fri, 22 Jun 2001 14:45:13 -0700 From: Ron Madaras Organization: Lawrence Berkeley Laboratory X-Mailer: Mozilla 4.72 [en] (WinNT; U) X-Accept-Language: en MIME-Version: 1.0 To: strauss@mail.nhn.ou.edu CC: Marek Zielinski , Daniel Elvira Subject: comments on the 630/1800 GeV photon PRL draft Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Length: 2559 Status: RO Mike, I read the 630/1800 GeV photon PRL draft, and have some comments. Ron 1) You did not use the latest author list, or the list of visitor addresses, though you did use the latest acknowledgment paragraph. Please check for the latest versions of the author list, list of visitor addresses, and the acknowledgment paragraph (see http://www-d0.fnal.gov/~madaras/authorlist.html) before you distribute another draft and before you submit the paper. Do not change or update the author list after the paper is submitted; it should stay frozen for your paper at the time of submittal. 2) I think that everywhere you use eta (mostly on p.4), you really mean eta_det (detector eta), which is different. I think you should change all the eta to eta_det, and define it. It is incorrect to use eta when you really mean detector eta. They are not the same. 3) p.4, 5th para: a) You say that the EC is 1.0 Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5PFwCP25648; Mon, 25 Jun 2001 10:58:12 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f5PFwBP01326; Mon, 25 Jun 2001 10:58:11 -0500 (CDT) Date: Mon, 25 Jun 2001 10:58:11 -0500 (CDT) From: Mike Strauss Message-Id: <200106251558.f5PFwBP01326@particle.nhn.ou.edu> To: RJMadaras@lbl.gov Subject: Re: comments on the 630/1800 GeV photon PRL draft Cc: marek@fnal.gov, strauss@mail.nhn.ou.edu Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: DFq1tY+50hnfykMU4kXu6A== Content-Length: 5170 Status: RO Ron, Thanks for reading the PRL draft and for your comments. I have responded below with changes. Please comment further if any of these changes are not satisfactory. -Mike > Mike, > > I read the 630/1800 GeV photon PRL draft, and have some comments. > > Ron > > > 1) You did not use the latest author list, or the list of visitor addresses, > though you did use the latest acknowledgment paragraph. > > Please check for the latest versions of the author list, list of visitor > addresses, and the acknowledgment paragraph > (see http://www-d0.fnal.gov/~madaras/authorlist.html) > before you distribute another draft and before you submit the paper. > > Do not change or update the author list after the paper is submitted; it > should stay frozen for your paper at the time of submittal. I have updated the author list. > 2) I think that everywhere you use eta (mostly on p.4), you really mean eta_det > (detector eta), which is different. I think you should change all the eta > to eta_det, and define it. It is incorrect to use eta when you really mean > detector eta. They are not the same. Actually, I am using eta, and not eta_det. The eta is calculated from the actual interaction vertex. So this is correct. One of my selection criteria is on eta_det, but the eta used is not eta_det. > 3) p.4, 5th para: > > a) You say that the EC is 1.0 there are 4 EM layers. This gives the impression that the ECEM covers > 1.0 > > > b) You say that the 4 sections of the EM calorimeter have 2, 2, 7 and 10 > radiation lengths. This is not true of the ECEM, which has 0.3, 2.6, > 7.9 and 9.3 radiation lengths. This should be changed. It is not easy to address these points while being accurate, and brief. I have changed the sentences to: The calorimeter provides full azimuthal ($\phi$) coverage, and consists of a central cryostat (CC) with $|\eta | \simle 1.0$, and two forward cryostats (EC) with $1.0 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is divided into four longitudinal layers, EM1--EM4, of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. The problem with this is that it still may still leave the impression that the EM calorimeter covers the mentioned eta. But there are "approximately equal" signs and it is hard to state what the calorimeter does actually cover. An alternative reading could just focus on the EM calorimeter and say The electromagnetic calorimeter provides nearly full azimuthal ($\phi$) coverage, and consists of a central cryostat (CC) with $|\eta | \simle 1.2$, and two forward cryostats (EC) with $1.3 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is divided into four longitudinal layers, EM1--EM4, of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. The problem with this reading is that I do use the hadronic calorimeter to filter out hadronic background. Which do you prefer? > 4) p.4, 2nd col, para starting "Photon candidates within...": You say "The > transverse energy around any cluster...", but it is not clear if the > transverse energy is EM energy or total (EM+hadronic) energy. Please > make this clear. It is total, and I have added the word "total". > 5) p.5, 7th line: You talk about EM1 and the first absorber plate. ECEM1 > does not have the usual thick absorber plate in front of it. See D0 > Note 757 (or our NIM papers). Your discussion gives slightly the wrong > impression. Could it be changed? Changed this to Photons only have a small probability of showering in material in front of the calorimeter and, thus, tend to deposit very little energy in EM1. > 6) In the first few paragraphs, you explicitly set up the hypothesis that the previous > single photon production excess at low Et is due either to gluon > radiation or PDF, and that by now taking the ratio you minimize the > sensitivity to PDF. Then at the end of the paper you show that there > is good agreement between the ratio and the theory. Thus the logical > conclusion is that the excess at low Et for the single photon production > is due to PDF. But you never conclude this in the paper. Why not? After > setting up the hypothesis that the excess is due to either A or B, and > then you show that the excess goes away when you remove B, why don't you > explicitly conclude that the excess is due to B? > I think the situation is not that simple. There is still a discrepency at low E_T in the ratio, primarily from the 630 measurement. In the CC, the three lowest bins are all 1 sigma high. The paper is already quite long, (maybe too long), so with the large errors on the points, I have taken the conservative approach by quoting a chi^2 probability, but not making any more definitive statements. With such large errors on the measurement, I think this is prudent. Again, thanks for your comments and please feel free to respond again to any of these changes or anything else in the paper. -Mike ------------------------------------------------------------------- From: Hugh Montgomery Organization: Fermi National Accelerator Laboratories Precedence: normal To: marek@fnal.gov, strauss@physast.nhn.ou.edu Cc: mont@fnal.gov, Jianming Qian Subject: 630-1800 GeV photon XS ratio PRL for collaboration review Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 25 Jun 2001 15:21:40 CDT Sender: mont Mike, Marek et al, I read your paper again over the weekend. I think it is basically fine and should be submitted. These damned single photons are so seductive but so painful! My comments are few and should be taken as just that, not demands, make your own call as to whether to ignore or not. Well done, Mont ============================================================================== Montgomery Comments ___________________ o page 4, para 3, I look for a different phrase than "This comparison reduces systematic..." because the comparison does not do anything itself. Perhaps " In the ratio, the systematic undertainties are reduced and the sensitivity .... is minimised." or similar. o page 4, para 8, perhaps my memory is faulty but I have in mind cuts EM fraction higher than 96%. Does the use of this value require a comment? o page 4, para 8, the phrase "... extrapolate to within a road.." read funnily. if we extrapolate then why not to a circle or ellipse at the calorimeter... and if its meant to indicate a solid within the tracking volume, I find myself wanting to use "cone" .. probably this use of road was established as a standard way-back when but on thinking, its a bit strange. o page 5, para 1, " .. tend to deposit very little.." I might remove very.. in my mind I am thinking that electrons are not so different... but maybe thats not the point. o page 5, para 1, last sentence, "The detector responses.... EM1 corrected to match the data..." why not use "calibrated " ? "corrected" may be the way we did it historically but thinking more globally, this is just an "in situ" calibration. o page 5, para 2, change "The distribution .. from the data are fitted .." to "The distribution .. from the data is fitted .." o page 5, para 3, change "The final cross section...... and purity corrections, is shown ..." to (two corrections) "The final cross sections ...... and purity corrections, are shown ..." o page 7, Figure 5. replace the theory sybols with a line (hand-drawn is fine) which goes through the theory points (but of course does not extrapolate) - --PAA14933.993500502/d0mino.fnal.gov-- ------------------------------------------------------------------- From qianj@umich.edu Tue Jun 26 09:10:48 2001 Return-Path: Received: from harumscarum.mr.itd.umich.edu (harumscarum.mr.itd.umich.edu [141.211.125.17]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5QEAmO23888 for ; Tue, 26 Jun 2001 09:10:48 -0500 Received: from d0nt1 (d0nt1.physics.lsa.umich.edu [141.211.101.171]) by harumscarum.mr.itd.umich.edu (8.9.3/3.3s) with SMTP id KAA04376; Tue, 26 Jun 2001 10:10:47 -0400 (EDT) Message-ID: <003301c0fe49$e0da3b40$ab65d38d@physics.lsa.umich.edu> Reply-To: "Jianming Qian" From: "Jianming Qian" To: , , "Daniel Elvira" Subject: comments on the 630 GeV photon PRL Date: Tue, 26 Jun 2001 10:11:22 -0400 Organization: The University of Michigan MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2462.0000 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2462.0000 Status: RO Content-Length: 1214 Hi Mike and Marek, The paper is well written. My only significant comment is that it is too long for PRL. You probably need to remove either a figure or a table to fit into PRL length. A couple of minor comments: 1) page 4, left column, first paragraph, last line: "... from jet identification and fragmentation" => "...from fragmentation and jet identification." 2) page 4, right column, the paragraph begins with "Photon candidates within...", line 10: The square should be on the differences, not only eta and phi themself. So please add brackets: "\sqrt{(\Delta\eta)^2+(\Delta\phi)^2}". 3) page 6, Table I, caption: It appears that Ref. 13 is hardwired. If so, change it to "\protect\cite{...}". It adds some robustness if you late need to add/remove references. 4) page 7, Fig. 5: In the jet ratio paper, theoretical values are shown in curves for several different normalization scales and different PDFs. I think curves are better. In the current form, the theory points are invisible when they are on top of data points. That's it. Please note that you need to respond to individuals who comment on the paper before we can close the collaboration after the deadline. -- Jianming ------------------------------------------------------------------- From RJMadaras@lbl.gov Tue Jun 26 16:01:24 2001 Return-Path: Received: from postal1.lbl.gov (postal1.lbl.gov [128.3.7.82]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f5QL1NO20230 for ; Tue, 26 Jun 2001 16:01:23 -0500 Received: from SpamWall.lbl.gov (localhost [127.0.0.1]) by postal1.lbl.gov (8.11.2/8.11.2) with ESMTP id f5QL1MX14210 for ; Tue, 26 Jun 2001 14:01:22 -0700 (PDT) Received: from lbl.gov (d0lblv.lbl.gov [128.3.2.50]) by SpamWall.lbl.gov (8.11.2/8.11.2) with ESMTP id f5QL1L914196; Tue, 26 Jun 2001 14:01:21 -0700 (PDT) Sender: madaras@lbl.gov Message-ID: <3B38FA06.86C9EDD0@lbl.gov> Date: Tue, 26 Jun 2001 14:09:26 -0700 From: Ron Madaras Reply-To: RJMadaras@lbl.gov Organization: LBL X-Mailer: Mozilla 4.73C-CCK-MCD LBNL V4.73 Build 1 [en] (X11; U; IRIX 6.5 IP32) X-Accept-Language: en MIME-Version: 1.0 To: Mike Strauss CC: marek@fnal.gov Subject: Re: comments on the 630/1800 GeV photon PRL draft References: <200106251558.f5PFwBP01326@particle.nhn.ou.edu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Status: RO Content-Length: 5843 Mike, Thanks. I have 3 comments on your replies, which I've indicated with ***. Ron Mike Strauss wrote: > > Ron, > Thanks for reading the PRL draft and for your comments. > I have responded below with changes. Please comment further if > any of these changes are not satisfactory. > > -Mike > > > Mike, > > > > I read the 630/1800 GeV photon PRL draft, and have some comments. > > > > Ron > > > > > > 1) You did not use the latest author list, or the list of visitor addresses, > > though you did use the latest acknowledgment paragraph. > > > > Please check for the latest versions of the author list, list of visitor > > addresses, and the acknowledgment paragraph > > (see http://www-d0.fnal.gov/~madaras/authorlist.html) > > before you distribute another draft and before you submit the paper. > > > > Do not change or update the author list after the paper is submitted; it > > should stay frozen for your paper at the time of submittal. > > I have updated the author list. *** And also the list of visitor addresses? > > > 2) I think that everywhere you use eta (mostly on p.4), you really mean > eta_det > > (detector eta), which is different. I think you should change all the eta > > to eta_det, and define it. It is incorrect to use eta when you really mean > > detector eta. They are not the same. > > Actually, I am using eta, and not eta_det. The eta is calculated from > the actual interaction vertex. So this is correct. One of my selection > criteria is on eta_det, but the eta used is not eta_det. *** When you make the cuts on photons, eta<0.9 or 1.6 > > 3) p.4, 5th para: > > > > a) You say that the EC is 1.0 > there are 4 EM layers. This gives the impression that the ECEM covers > > 1.0 > > > > > > > b) You say that the 4 sections of the EM calorimeter have 2, 2, 7 and 10 > > radiation lengths. This is not true of the ECEM, which has 0.3, 2.6, > > 7.9 and 9.3 radiation lengths. This should be changed. > > It is not easy to address these points while being accurate, and brief. > I have changed the sentences to: > > The calorimeter provides > full azimuthal ($\phi$) coverage, and consists > of a central cryostat (CC) with > $|\eta | \simle 1.0$, and two forward cryostats (EC) with > $1.0 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is > divided into four longitudinal layers, EM1--EM4, > of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. > > The problem with this is that it still may still leave the impression that > the EM calorimeter covers the mentioned eta. But there are "approximately > equal" signs and it is hard to state what the calorimeter does actually > cover. > > An alternative reading could just focus on the EM calorimeter and say > > The electromagnetic calorimeter provides > nearly full azimuthal ($\phi$) coverage, and consists > of a central cryostat (CC) with > $|\eta | \simle 1.2$, and two forward cryostats (EC) with > $1.3 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is > divided into four longitudinal layers, EM1--EM4, > of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. > > The problem with this reading is that I do use the hadronic calorimeter > to filter out hadronic background. > > Which do you prefer? *** I prefer the second paragraph, since the photon detection is primary. *** But I think it is more common to characterize the CCEM as |eta|<1.1 *** and the ECEM as 1.4<|eta|<4.0. > > > 4) p.4, 2nd col, para starting "Photon candidates within...": You say "The > > transverse energy around any cluster...", but it is not clear if the > > transverse energy is EM energy or total (EM+hadronic) energy. Please > > make this clear. > > It is total, and I have added the word "total". > > > 5) p.5, 7th line: You talk about EM1 and the first absorber plate. ECEM1 > > does not have the usual thick absorber plate in front of it. See D0 > > Note 757 (or our NIM papers). Your discussion gives slightly the wrong > > impression. Could it be changed? > > Changed this to > > Photons only have a small probability of showering in > material in front of the calorimeter and, thus, > tend to deposit very little energy in EM1. > > > 6) In the first few paragraphs, you explicitly set up the hypothesis that the > previous > > single photon production excess at low Et is due either to gluon > > radiation or PDF, and that by now taking the ratio you minimize the > > sensitivity to PDF. Then at the end of the paper you show that there > > is good agreement between the ratio and the theory. Thus the logical > > conclusion is that the excess at low Et for the single photon production > > is due to PDF. But you never conclude this in the paper. Why not? After > > setting up the hypothesis that the excess is due to either A or B, and > > then you show that the excess goes away when you remove B, why don't you > > explicitly conclude that the excess is due to B? > > > I think the situation is not that simple. There is still a discrepency > at low E_T in the ratio, primarily from the 630 measurement. In the > CC, the three lowest bins are all 1 sigma high. The paper is already > quite long, (maybe too long), so with the large errors on the points, > I have taken the conservative approach by quoting a chi^2 probability, > but not making any more definitive statements. With such large errors > on the measurement, I think this is prudent. > > Again, thanks for your comments and please feel free to respond again > to any of these changes or anything else in the paper. > > -Mike ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Mon Jul 2 14:26:12 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62JOt913716; Mon, 2 Jul 2001 14:24:55 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f62JOsP06896; Mon, 2 Jul 2001 14:24:54 -0500 (CDT) Date: Mon, 2 Jul 2001 14:24:54 -0500 (CDT) From: Mike Strauss Message-Id: <200107021924.f62JOsP06896@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, daniel@fnal.gov, mont@d0mino.fnal.gov Subject: Re: 630-1800 GeV photon XS ratio PRL for collaboration review: resend Cc: marek@fnal.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: JU2PrjHKopTK14xEP2kPfw== Content-Length: 4041 Status: RO Mont, Thanks for your latest comments. I respond below. (Daniel and Marek, please read the last comment and response and let me know what you think). -Mike > Mike, Marek et al, > > I read your paper again over the weekend. I think it is basically fine > and should be submitted. These damned single photons are so seductive but > so painful! > > My comments are few and should be taken as just that, not demands, make > your own call as to whether to ignore or not. > > Well done, > > Mont > > ============================================================================== > Montgomery Comments > ___________________ > > o page 4, para 3, I look for a different phrase than > "This comparison reduces systematic..." because the comparison does not > do anything itself. Perhaps > " In the ratio, the systematic undertainties are reduced and the > sensitivity .... is minimised." or similar. > > o page 4, para 8, perhaps my memory is faulty but I have in mind cuts EM > fraction higher than 96%. Does the use of this value require a comment? Changed to: A ratio of the cross sections at different energies reduces systematic uncertainties and minimizes the sensitivity to the choice of parton distribution functions (PDF) because the measurements at both energies use the same detector and the same analysis method. > o page 4, para 8, the phrase "... extrapolate to within a road.." read > funnily. if we extrapolate then why not to a circle or ellipse at the > calorimeter... and if its meant to indicate a solid within the tracking > volume, I find myself wanting to use "cone" .. probably this use of road > was established as a standard way-back when but on thinking, its a bit > strange. This terminology was actually changed to the way it is currently written by the grammatical wizardry of Tom Ferbel. With such pristine pedigree I am reluctant to change it too much. > o page 5, para 1, " .. tend to deposit very little.." I might remove very.. > in my mind I am thinking that electrons are not so different... but maybe > thats not the point. No, the point has nothing to do with electrons or photons. It has to do with a single photon, or multiple photons. If photons deposit a lot of energy in EM1, then the probability for two to shower is not just twice that of the probability of one to shower. The terminology used is a consolidation of terminology suggested by John Krane and myself. I will remove the word "very" and just say "deposit little energy" > o page 5, para 1, last sentence, > "The detector responses.... EM1 corrected to match the data..." > > why not use "calibrated " ? "corrected" may be the way we did it > historically but thinking more globally, this is just an "in situ" > calibration. I like calibration better. I have changed it. > o page 5, para 2, change "The distribution .. from the data are fitted .." > to "The distribution .. from the data is fitted .." I can never remember if data is singular or plural. However, here you are correct that it is the distributions that is fitted and that is singular. > o page 5, para 3, change > "The final cross section...... and purity corrections, is shown ..." > to (two corrections) > "The final cross sections ...... and purity corrections, are shown ..." > Yes, you are correct again. Cross sections is plural. > o page 7, Figure 5. replace the theory sybols with a line > (hand-drawn is fine) which goes through the theory points (but of course > does not extrapolate) > There has been some discussion on how to present this. The problem with the line is that it looks strange. The horizontal band on the data point extends to .15 but the theory stops at the central value of .12. It makes the plot look very strange. I have tried both ways and prefer this one, but am willing to change if others think it is best. Daniel or Marek, any thoughts? ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Mon Jul 2 14:39:53 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62Jdj921406; Mon, 2 Jul 2001 14:39:45 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f62Jdjn06901; Mon, 2 Jul 2001 14:39:45 -0500 (CDT) Date: Mon, 2 Jul 2001 14:39:45 -0500 (CDT) From: Mike Strauss Message-Id: <200107021939.f62Jdjn06901@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, marek@fnal.gov, daniel@fnal.gov, qianj@umich.edu Subject: Re: comments on the 630 GeV photon PRL Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: oS/hOko39eSujrs6G3yLxg== Content-Length: 3313 Status: RO Jianming, Thanks for your comments. I respond below. I would appreciate help from others (Marek, Daniel?) in what should be left out if the paper is too long. (See the first comment). Jianming, what do you think should be dropped? Also, the comment about Figure 5 has come up again. (See last comment). -Mike > Hi Mike and Marek, > > The paper is well written. My only significant comment is that it is too > long for PRL. You probably need to remove either a figure or a table to fit > into PRL length. A couple of minor comments: Any suggestions on what to drop? > 1) page 4, left column, first paragraph, last line: > "... from jet identification and fragmentation" => "...from fragmentation > and jet identification." Done > 2) page 4, right column, the paragraph begins with "Photon candidates > within...", line 10: > The square should be on the differences, not only eta and phi themself. > So please add brackets: > "\sqrt{(\Delta\eta)^2+(\Delta\phi)^2}". Yes, that is better. I have changed this to make the definition of R unambiguous. > 3) page 6, Table I, caption: > It appears that Ref. 13 is hardwired. If so, change it to > "\protect\cite{...}". It adds some robustness if you late need to add/remove > references. I did hardwire it because I kept getting an error since the reference was in the caption. I didn't know about the \protect command, but that seems to have fixed the problem. > 4) page 7, Fig. 5: > In the jet ratio paper, theoretical values are shown in curves for > several different normalization scales and different PDFs. I think curves > are better. In the current form, the theory points are invisible when they > are on top of data points. Mont made the same comment. Here is my response. Mont said: > o page 7, Figure 5. replace the theory sybols with a line > (hand-drawn is fine) which goes through the theory points (but of course > does not extrapolate) > I said: There has been some discussion on how to present this. The problem with the line is that it looks strange. The horizontal band on the data point extends to .15 but the theory stops at the central value of .12. It makes the plot look very strange. I have tried both ways and prefer this one, but am willing to change if others think it is best. Daniel or Marek, any thoughts? Given that Mont and Jianminf have made the same suggestion, it seems like there is a consensus to draw a curve. However, there are some problems. Here are the problems: The theory is actually calculated at each of the midpoints in figure 5. If I draw a curve, then I do what Mont said and draw it "by hand" or I have to go back and ask the Theorists to calculate the 1800 GeV cross section in x_T bins that correspond to 1 GeV bins at 630 GeV. (I know Vogelsang would be willing to do this). If I draw the curve "by hand" then it stops at .12 even though the plot and the horizontal errors run out to .15. I tried this but didn't like how it looks. I could send you a ps file of how it looks. Thoughts? > That's it. > > Please note that you need to respond to individuals who comment on the paper > before we can close the collaboration after the deadline. I am responding to everyone and sending cc's to Daniel and Marek. Thanks for your comments. -Mike ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Mon Jul 2 14:46:55 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62Jkq921414; Mon, 2 Jul 2001 14:46:52 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f62Jkpg06905; Mon, 2 Jul 2001 14:46:51 -0500 (CDT) Date: Mon, 2 Jul 2001 14:46:51 -0500 (CDT) From: Mike Strauss Message-Id: <200107021946.f62Jkpg06905@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, RJMadaras@lbl.gov Subject: Re: comments on the 630/1800 GeV photon PRL draft Cc: marek@fnal.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: PrjUkPO1NoeJ/oILm/L4SQ== Content-Length: 2733 Status: RO Thanks Ron, I have edited your note and replied to your lastest comments in the line under those marked ***. > > I have updated the author list. > > *** And also the list of visitor addresses? Yes, I updated the author list, as well. > *** When you make the cuts on photons, eta<0.9 or 1.6 *** eta and not detector eta? Why? Yes, I do. The reason is because that is the physically significant variable from a theorists point of view. I check that the photon is also well within the detector so cut on eta_det, but that just folds into the efficiency. The variable plotted and used for analysis is eta because the theoretical calculations are done in an eta region, not in an eta_det region. > > It is not easy to address these points while being accurate, and brief. > > I have changed the sentences to: > > > > The calorimeter provides > > full azimuthal ($\phi$) coverage, and consists > > of a central cryostat (CC) with > > $|\eta | \simle 1.0$, and two forward cryostats (EC) with > > $1.0 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is > > divided into four longitudinal layers, EM1--EM4, > > of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. > > > > The problem with this is that it still may still leave the impression that > > the EM calorimeter covers the mentioned eta. But there are "approximately > > equal" signs and it is hard to state what the calorimeter does actually > > cover. > > > > An alternative reading could just focus on the EM calorimeter and say > > > > The electromagnetic calorimeter provides > > nearly full azimuthal ($\phi$) coverage, and consists > > of a central cryostat (CC) with > > $|\eta | \simle 1.2$, and two forward cryostats (EC) with > > $1.3 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is > > divided into four longitudinal layers, EM1--EM4, > > of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. > > > > The problem with this reading is that I do use the hadronic calorimeter > > to filter out hadronic background. > > > > Which do you prefer? > > *** I prefer the second paragraph, since the photon detection is primary. > *** But I think it is more common to characterize the CCEM as |eta|<1.1 > *** and the ECEM as 1.4<|eta|<4.0. OK. It is changed to The electromagnetic calorimeter provides full azimuthal ($\phi$) coverage, and consists of a central cryostat (CC) with $|\eta | \simle 1.1$, and two forward cryostats (EC) with $1.4 \simle |\eta | \simle 4.0$. The eletromagnetic CC (EC) is divided into four longitudinal layers, EM1--EM4, of 2, 2, 7, and 10 (0.3, 2.6, 7.9 and 9.3) radiation lengths, respectively. Again, thanks for your comments. -Mike ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Mon Jul 2 14:51:12 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62Jnu916754; Mon, 2 Jul 2001 14:49:56 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f62JntB06909; Mon, 2 Jul 2001 14:49:55 -0500 (CDT) Date: Mon, 2 Jul 2001 14:49:55 -0500 (CDT) From: Mike Strauss Message-Id: <200107021949.f62JntB06909@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, daniel@fnal.gov, mont@d0mino.fnal.gov Subject: Re: 630-1800 GeV photon XS ratio PRL for collaboration review: resend Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: EXP59GN5UZeFMI9L1PocAA== Content-Length: 271 Status: RO I forgot to respond to this one, and Sharon made the same comment. > o page 4, para 8, perhaps my memory is faulty but I have in mind cuts EM > fraction higher than 96%. Does the use of this value require a comment? > Changed to "have more than 96%" -Mike ------------------------------------------------------------------- From hagopian@hep.fsu.edu Mon Jul 2 13:41:47 2001 Return-Path: Received: from r2d2.hep.fsu.edu (root@r2d2.hep.fsu.edu [128.186.110.40]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62Ifk920782 for ; Mon, 2 Jul 2001 13:41:46 -0500 Received: from lnxc13.hep.fsu.edu (IDENT:root@lnxc13.hep.fsu.edu [128.186.110.173]) by r2d2.hep.fsu.edu (8.11.4/8.11.4) with ESMTP id f62IhVP17858 for ; Mon, 2 Jul 2001 14:43:31 -0400 (EDT) Received: from localhost (hagopian@localhost) by lnxc13.hep.fsu.edu (8.9.3/8.9.3) with ESMTP id OAA30500 for ; Mon, 2 Jul 2001 14:43:29 -0400 X-Authentication-Warning: lnxc13.hep.fsu.edu: hagopian owned process doing -bs Date: Mon, 2 Jul 2001 14:43:29 -0400 (EDT) From: Sharon Hagopian 850-644-4777/630-840-8384 X-X-Sender: To: Subject: comments on 630/1800 photon xsect ratio PRL draft (fwd) Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Content-Length: 1913 Status: RO ---------- Forwarded message ---------- Date: Mon, 2 Jul 2001 14:38:49 -0400 (EDT) From: Sharon Hagopian 850-644-4777/630-840-8384 To: strauss@physast.nhn.ou.edu, Marek Zielinski Cc: daniel@fnal.gov Subject: comments on 630/1800 photon xsect ratio PRL draft Dear Mike and Marek, I am glad to see that the 630 GeV direct photon results are ready for publication. Below are a few comments. Good-luck in getting this paper published in the near future. Regards, Sharon ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1. Page 4, col. 1, end of paragraph 2 - could add a sentence: For a recent summary of experimental results and theoretical status see the Report of the Fermilab QCD and Weak Boson Run II Workshop [hep-ph/0005226]. 2. Page 4, col. 2, paragraph 3, line 6 - better to say "have more than 96%" or "96% or more" whichever is the case. 3. Page 5, col. 1, paragraph 1, line 23 - consider changing "data, thus minimizing constraints from the tracking efficiency" to "data, thus minimizing uncertainties from the tracking efficiency". 4. Page 5, col. 1, Figure 1 - Is the two peak structure in curve (a) and the data due to one photon depositing almost no energy in E1, but two photons depositing more and making the 2nd peak? If so, having a separate MC curve for two photons from pi zeros might make this clearer. 5. Page 5, col. 2, Figure 2 - The E_T for the last bin (29.75-49.0) for abs(eta) between 1.6 and 2.5 only has a photon purity of ~10%, giving an error of %160. Wouldn't it be better just to drop this point? 6. Page 6, col. 1, end of paragraph 1 - Could add a sentence: "Such deviations between theory and data for low E_t(gamma) have been seen in previous experiments [2-6]." to remind the reader. ------------------------------------------------------------------- From strauss@phyast.nhn.ou.edu Mon Jul 2 15:14:53 2001 Return-Path: Received: from particle.nhn.ou.edu (particle.nhn.ou.edu [129.15.30.205]) by phyast.nhn.ou.edu (8.10.2/8.10.2) with ESMTP id f62KEp923308; Mon, 2 Jul 2001 15:14:51 -0500 Received: by particle.nhn.ou.edu (8.10.2/8.10.2) id f62KEo306920; Mon, 2 Jul 2001 15:14:50 -0500 (CDT) Date: Mon, 2 Jul 2001 15:14:50 -0500 (CDT) From: Mike Strauss Message-Id: <200107022014.f62KEo306920@particle.nhn.ou.edu> To: strauss@mail.nhn.ou.edu, hagopian@hep.fsu.edu Subject: Re: comments on 630/1800 photon xsect ratio PRL draft (fwd) Cc: marek@fnal.gov, daniel@fnal.gov Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-MD5: IoN0cSGhDODX72a9zAD2GQ== Sharon, Thanks for reading the paper and for you comments. I have responded below. -Mike > 1. Page 4, col. 1, end of paragraph 2 - could add a sentence: > For a recent summary of experimental results and theoretical status > see the Report of the Fermilab QCD and Weak Boson Run II Workshop > [hep-ph/0005226]. The paper is already long. I could add this as another reference, but I am more inclined just to leave it out. > 2. Page 4, col. 2, paragraph 3, line 6 - better to say "have more than 96%" > or "96% or more" whichever is the case. Good point. Changed to "have more than 96%". > 3. Page 5, col. 1, paragraph 1, line 23 - consider changing "data, thus > minimizing constraints from the tracking efficiency" to "data, thus > minimizing uncertainties from the tracking efficiency". I like your wording better. Done. > 4. Page 5, col. 1, Figure 1 - Is the two peak structure in curve (a) and > the data due to one photon depositing almost no energy in E1, but two > photons depositing more and making the 2nd peak? If so, having a > separate MC curve for two photons from pi zeros might make this clearer. That is not the reason for the two peaks in (a). Curve (a) is single photons only. I'm not sure the reason for the two peak structure. I know the lowest points are the photons that deposit almost no energy in E1, but I don't know why there is a dip between that and background (which is dominated by two photons from pi zeros, etc.) and is shown in curve (b). I will add the word "single" in the explanation of (a) to make it clear this is the signal only. The caption now says: "...Points with error bars indicate data. Broken lines indicate simulated distributions of (a) single photons, and jet background (b) without and (c) with charged tracks. The solid line depicts a fit sum of all three distributions." > 5. Page 5, col. 2, Figure 2 - The E_T for the last bin (29.75-49.0) > for abs(eta) between 1.6 and 2.5 only has a photon purity of ~10%, > giving an error of %160. Wouldn't it be better just to drop this point? This has been discussed. I can't change the binning of the points because I am comparing with 1800 GeV whose x_T bins are set. The consensus of the EB was just to keep the point since the errors are correct, even though it doesn't add much to the analysis. > 6. Page 6, col. 1, end of paragraph 1 - Could add a sentence: > "Such deviations between theory and data for low E_t(gamma) have been > seen in previous experiments [2-6]." to remind the reader. > Because the discrepency between theory and data is not too significant in this measurement, I have had a number of suggestions as to whether that discrepency should be emphasized more, or emphasized less. Your remark would be put on the "more" side. I am satisfied with where things are now, stating the chi^2 for the whole fit, stating that the deviations exist, but not overemphasizing the problem. Thus, I am inclined to leave it as it is. Again, thanks for your comments and suggestions. -Mike