2018-06-25 referees-meeting

Previous meeting

Monday 25th June at 16:00 BST

Phone line:

UK Freephone: 08006948053
Caller PIN: 6783834683

Discussion of Note

Discussion of the MICE Note MCSNote.pdf


John Nugent
Chris Rogers
Paul Soler
Ken Long
John Cobb
Mariyan Bogomilov

Table 1:
  • Done
Figure 1:
  • Moved now to Fig. 14; legend is still tiny
Table 2b:
  • Done
  • Neither Moliere nor Carlisle-Cobb use radiation length; quote density as well.
  • Please write "using the expression from the PDG"
Figure 2:
  • JHC: Why are there such fluctuations in the dx/dz MC plot? Is it a statistics issue? JN: There are 10x statistics in MC CR: there are three distributions on top of each other
  • PS: Could consider the systematic discrepancy between MC and data in e.g. x'
  • JHC: Define the selection before showing fig. 2
Table 3:
  • Force latex to move the table to after Section 3.x
  • Upstream track selection - duplication of 69.13 % looks like a bug; JN will check
  • Diffuser cut text - define the radius
  • Inconsistent r0 in text
  • "45 degrees" -> explained in the text
  • Move equations out of the table and into the text
  • Note that the TOF cut for Table 3 has changed the statistics sample by factor 2
Fig. 3
  • Figure 3b should be a histogram
  • Move to near S3.4 (and move fig. 13 forwards)
  • Extrapolated distance is quite large; check number on envelope and add in MC
  • Note that the statistics in 3c is rather small. Should enhance statistical size
  • Add no hydride data
Fig. 4:
  • Legend too small

KL: Plot chi2 MC vs data; consider adding chi2 selection

Fig. 5:
  • Doesn't show the selection cuts!; update so that it does actually show what the fiducial cut is
  • Put scale in; e.g. relative to z = 0 m
Fig. 6:
  • Add TOF12 resolution
  • Show TOF12 momentum recon
  • Why is 6d double peaked (before the correction)
  • Fig. 6c has incorrect MAUS version stamp
  • Fig. 6b points are at centre of each TOF bin;
  • Add text to say what fig. 6b shows; put the formula in the text
Fig. 7-10:
  • Fig. 8f why is there an event at x > 140 mm? JN: Cuts are made upstream, small probability of track scattering out of TKD
  • Fig. 8d Why is there an event at r > 150 mm? JN: I don't know, but they get removed by fiducial; PS: tracker can make a track with r > 150 mm
Fig. 11 and 12:
  • 12(a) Try moving by half a bin; is it a fluctuation or a feature?
  • 11(a) A mild misalignment is noted; JN notes that the misalignment has been fixed.
Fig. 13
  • Use thicker markers; move before fig. 11 and 12
Fig. 14
  • Caption "generated" -> "calculated"; scattering distributions -> "theoretical scattering distributions"
  • Should say MICE internal
Fig. 15
  • 15(a) what is going on at -40 mrad? Comparison with positive delta x of data and negative delta x of data
  • Error bars may be underestimated; please review error bar calculation.
  • Make asymmetry plots for "red curve" in Fig. 15
Fig. 16
  • Deconvolution is systematically not producing the correct answer
  • JN: try using Gold's algorithm
  • JN: used 10 iterations; not really a firm foundation for "10"
  • KL: potential left-right asymmetry
  • JHC: What about acceptance correction? JN: it makes the deconvolution worse so I took it out;
  • JHC: Some events scatter in and then out; these will make the deconvolution imperfect; JN: use virtual planes on LiH to do the analysis (which does not have an acceptance associated); JHC virtual planes on LiH does not include effect of trackering scattering
  • JN: Look at convergence of deconvolution;

JHC: Recommend abandoning deconvolution; publish on convolution only plus MC of data
PS: Wants to keep trying on deconvolution

  • PS: would like a summary table of systematic errors
Fig. 19
  • JN: Disagreement probably arises due to deconvolution, not data
Fig. 18
  • JHC: Why are error bars so small? PS: the errors are statistically dominated; how does it look with statistical errors only?
Fig. 20
  • 3D distribution looks weird at low momentum
  • Note asymmetry in 2D distributions
General discussion:
  • JHC - should we really bother with cobb+carlisle? JN - well why not? we can discuss for the paper
  • JN: if we abandon deconvolution don't we have to do forward convolution? JHC: no we just compare empty and full data with MC
  • JN: try Gold's algorithm - couple of days work

MCSNote.pdf (1.47 MB) Rogers, Chris, 22 June 2018 12:40