WalkingAlbatross < Sandbox/Sandbox

Low-level AD performance
1. PMT gain
  1. Definition
  2. Measurement technique(s). Include example figure(s).
  3. Charge Stability Figure: Mean AD1,2 gains compared vs time
  4. Charge Uniformity Figure: AD1,2 comparison of gain distributions
2. PMT dark rate
  1. Definition
  2. Measurement technique
  3. PMT Dark Rate Stability Figure: Mean AD1,2 dark rates vs time
3. Problem PMTs, such as flashers, or other instrumental backgrounds and features. Just in case
  1. Characterisitics
  2. How treated for analysis in this paper?
4. Electronics performance.
  1. Noise Level Figure: Channel hit rates vs. threshold for AD1,2 Figure: Channel hit rates vs. time for AD1,2 using forced triggers
  2. Charge Stability: Figure: AD1 and AD2 pedestal (preADC) and charge ($\Delta$ADC) vs. time
5. Trigger
  1. Stability Figure: AD1,2 trigger rates vs time for multiplicity and energy sum triggers
  2. Efficiency Figure: AD1,2 efficiency vs energy for multiplicity and energy sum triggers.
6. AD system stability/uptime: Figure: Total livetime for each AD as a function of time.
Comparison of rates and energy spectra. When comparing rates and energy spectra, we suggest using a common energy range of 0 to 12 MeV. This range provides a $\sim$4~MeV background window above the IBD region. This range displays confidence about higher energy backgrounds, while not overwhelming the region of interest. We may consider including a single figure that shows backgrounds at higher energies if needed.
1. Calibration sources
  1. Description of source activities, positions, decay products, and spectral shape
  2. Description of selection criteria
  3. Energy Identicality Figure: Spectral comparison and ratio for AD1,2
  4. Efficiency Stability Figure: Rate vs time comparison and ratio for AD1,2
  5. Figure: Rate and spectral comparisons as a function of source position? This demonstrates identicality of response throughout the AD.
  6. Options and discussion: How to evaluate the measured source rates?
    1. One straightforward option is to count events in a background-subtracted spectrum after application of energy cuts.
    2. Another option is to use the results of fits. Comment: Should this choice be determine by the approach with the smallest systematic uncertainty?
2. Spallation neutrons
  1. Description of source of spallation neutrons
  2. Description of selection criteria
  3. Energy Identicality Figure: Spectral comparison and ratio for AD1,2
  4. Efficiency Stability Figure: Rate vs time comparison and ratio for AD1,2
  5. Efficiency Identicality Figure: Capture time comparison and ratio for AD1,2
  6. Options and discussion: Do we need to show nH and nGd capture peaks separately? Comparsion of nH and nGd relative rates is a measure of Gd/H ratio but probably not as meaningful as a comparison of capture time distributions. Extraction of relative rates of capture from nH and nGd peaks is likely to be complex. Comment: We can produce a clean nH energy peak if this is useful for the publication. Extracting the Gd/H ratio is limited due to the contribution of nH captures in the acrylic, LS, and MO regions. Studies of using the AmC source for such a measurement are also challenging.
3. All AD triggers
  1. Description of likely sources of observed features in spectra
  2. Description of selection criteria
  3. Energy Identicality Figure: Spectral comparison and ratio for AD1,2
  4. Efficiency Stability Figure: Rate vs time comparison and ratio for AD1,2
  5. Options and discussion: It has been proposed we show spatial- or position-dependence of rates and efficiencies.
    1. Our singles rates are equally distributed in the detector Comment: I would not be surprised to find some variation in the singles backgrounds between the two ADs.
    2. Our spallation neutron detection efficiency is consistent at all positions in both ADs Comment: We expect that the nGd capture efficiency will decline near the GdLS boundary due to partial gamma escape. It may be possible to show the ratio of AD1/AD2 efficiency vs. reconstructed $\rho$ and $z$. Are the differences in these ratios attributed to vertex reconstruction or true efficiency differences?
    3. Our detected IBD rates are consistent at all positions in both ADs. (Note that IBD rates should differ by $\sim\!2\%$ due to baselines .) Comment: See comment about spallation neutron distributions. The same issues apply, with the addition of the slight position variation in IBD rate due to the baseline.
4. All AD triggers after muon veto
  1. Description of muon veto
  2. Description of suppression or enhancement of features
  3. Energy Identicality Figure: Spectral comparison and ratio for AD1,2
  4. Efficiency Stability Figure: Rate vs time comparison and ratio for AD1,2
5. After IBD selection
  1. Description of IBD reaction and products, and any residual backgrounds
  2. Description of selection criteria
  3. AD Identicality Figure: Side-by-side AD1,2 comparison of prompt vs delayed energy spectra
  4. AD Stability Figure: Relative IBD rate vs time. Comparison with predicted ratio given observed thermal power and nominal baselines. This comparison would be quite convincing. It could be complicated if significant background remains after all cuts.

Revision: r2 - 2011-09-04 - 05:22:05 - DavidJaffe

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