2020-06-11 analysis

Paul Kyberd
Ken Long
Dan Kaplan
John Cobb
Paul Jurj
Chris Rogers
Tom Lord
Craig Brown

PJ showed us plot of change in emittance with emittance with fit line.

KL: Did you estimate the size of the shift due to Al? PJ: No. The relationship is complicated due to slight differences in beta function.

JHC: Agreement of blue dots and line for LiH is pretty good. No absorber effect is reasonable. Note that the lH2 and no absorber look quite consistent.

DK: One could validate the Al explanation. Encouraged to check.

KL: Showed fits by eye to various lines. Note difference in slope. Propose we do no show "theory line" because agreement is still needing work.

JHC: You could probably even do better.

DK: Why are the error bars smaller than previous version? PJ: Improvements to correction procedure.

DK: How do we describe the error bars; they are partly statistical and systematic? KL: Make sure that the errors are only statistical. PJ: The errors get rather small if we don't include the "systematic" effects. KL: The error is not really "systematic", it is statistical, even though it is "MC statistical".

JHC: Can't get to the MICE note to check his error analysis as is down. DK: Working on it. PK: PF has a copy.

PK: Have we agreed that the theory line will not be on the plot? PJ: Yes. PK: Is there a motivation to put a fit line on? KL: will the fit get distorted by corrections.

JHC: What about the suppressed zero? PJ: We don't have enough statistics at low emittance. JHC: would be nice to use additional samples. PJ: yes, it is a work in progress. CR: we won't do it by Monday

DK: Why don't the points have same emittance at TKU? PJ: Fluctuations in the parent distribution tend to pull the plot.

JHC: Fit to the blue points and compare CR: Good idea but we can't do it by Monday. JP: Note that the theory slope is shown on slide 3. DK: note beta changes significantly over the absorber.

JHC: What is the best absorber? PJ: lH2 has smaller eqm emittance. KL: LiH is easier to handle.

JP: To be clear, what do we agree? CR: We agree to keep errors the same with comment on the plot to the effect that there are no systematic errors.

KL: Do the branding carefully! These will live with us for two years.

KL: Watch LH2 in the legend
CR: varepsilon not epsilon
JHC: Horizontal axis starts at 1.0
CR: vertical axis starts at -0.5 mm

JHC, KL, DK, CR: Great plots! Well done for these and also Tom et al!

Updated by Rogers, Chris almost 4 years ago · 4 revisions