Emittance Paper Referees Meeting¶

11th April 2018 at 15:00 BST, meeting room will be CR23, or phone:

UK Freephone: 08082380274
US Toll free: 631.621.5253

Caller PIN: 177 933 9517

• previous meeting

Agenda¶

The outcome of the meeting should be a set of specific actions to create additional plots, tables, etc that the referees feel are required to support the paper.

• Presentation of the MICE Note
  • 2018-03-29-Emit-Note.pdf (Blackmore)

Notes¶

Present¶

Scott Berg
Paul Kyberd
Chris Hunt
Victoria Blackmore
Chris Rogers

Abstract:¶

"reconstruct the emittance" -> "reconstruct the distribution"
Add a phrase to indicate "not only can we do it, but we get it right"

Section 1:¶

Para 1: the e+ e- collider will require cooling or <some magic>; so we can be
more assertive

Para 2: phrasing of "is subsequently accelerated" is a bit mangled; improve wording

Concern: we don't make it clear that where the MC and data disagree, we need to
emphasise that the disagreement does not compromise the method. Response: it is
hard to justify things without just wildly speculating. Agree: Especially in the MICE
note we need to document why we are using a wrong energy beam, what the shortcomings are
and why we think its okay.

Para 3: again "reconstruct emittance" as per abstract

Section 2:¶

Add a reference to where its done in more detail.

Last para last sentence - needs straightening out

Para 2 just before eqn (1) normalised transverse emittance "is" -> "characterises/approximates"

Scott comments that section 2 is a bit light on detail/motivation.

Section 3:¶

Reference for diffuser please

The phrasing regarding "the most downstream surface of the scintillating-fibre plane closest to the absorber/focus coil module" is confusing - need to specify the most downstream plane of the upstream tracker. Add a line in Fig. 1?

Section 4:¶

title: Should be a "transfer line" or "beam line" but definitely not a "beam". Need agreement between Scott and Ken Long.

last para: 700 MeV/c -> MeV

last line: "uniform" -> "effectively uniform"

Section 5:¶

Mention 700 vs 800 MeV

Second paragraph second line 800 MeV not 800 MeV/c

"simulated using G4Beamline" -> "produced using G4Beamline"

be consistent with ToF vs TOF

Section 6:¶

Need more discussion of discrepancies between MC and data

Note discrepancy between MC and data; there is no glue in the MC (rather He)

Normalised Time-of-Flight bullet

• Explain that MC vs data TOF01 has a different electron peak
• "normalised" -> "calibrated"
• "1 <= t_n01 <= 6" -> "1 <= t_n01 <= 6 ns". Explain purpose of the cut a bit better

Other bullets

• Add a little more clarity on why there is a "single track reconstructed" cut
• "Events for which... are ascribed to the passage of pions". Reference Table 2.

Plots (in general):

• Font sizes need to be bigger

Figure 5:

• Comment on y-distribution

Section 7:¶

Section 7.2¶

Fig. 8, Fig. 9: add some more text to discuss them

• A bit more interpretation on Fig. 8
• Specify that Fig. 9 justifies the momentum selection
  Juggle section 7.2; e.g. the paragraph on statistical uncertainty is a bit "out of nowhere"

Section 7.3¶

Propose put Fig. 13 (emittance) to "start things out" and then explain where the error bars come in
e.g. do the results; then do the statistical and systematic uncertainties

Section 7.3.1¶

Add a table showing - how much each cut was varied and the resultant change in emittance

Section 7.3.2¶

Split paragraph 1 into section on "p" and "x, px, y, py". Explicitly state which
line of Table 3 corresponds to which error.

Section 7.3.5¶

Add a reference to Holger presentation (or equivalent) for the COMSOL model.
Ensure Holger is on the author list of the paper.

last sentence para 1: what is the "known field model"? Explain that we have two
models; COMSOL and MAUS; and be explicit about what we are talking about.

para 3: what does the last sentence mean? Clarify.

para 4: "to the correct the emittance values" -> "to correct the emittance values"

Table 3: why is the +0.08 for 230 MeV/c diffuser so large?

Section 7.4¶

Fig. 13: the MC and data do no agree. Is this a problem?

• KL: we will not show MC in the publication.

Explicitly say that the MC disagrees because the generated beam is not right, etc.

Fig. 14: "the residual emittance is approximately flat" -> quote a chi2

Consider removing the 180 MeV/c bin.
Quote the chi2 for Fig. 14

Para 1: dispute the assertion that Fig. 13 MC is flat between 195 and 225

Section 8¶

Comment on the rather large emittance uncertainty; how do we square that with the goals of MICE

"mean emittance of" -> "mean value of"
"apertures leading to" -> "aperture upstream of"

Agree: we will meet again with final draft of MICE note and first draft of paper; propose Monday 23rd April for next iteration of the paper.