A kind of analysis

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-peak positions are shifted w.r.t. each other due to the difference in TOF conversion (electronics amplification). If we wanna calculate the asymmetry as a function of TOF for each channel (neutron energy) it is necessary to match the positions of centroids of -peaks. However, one needs to take into account the difference between channel-to-TOF calibration coefficients for each detector.

This is what we have if we superimpose TOF-spectra within one plot. It was used used the average channel-to-TOF calibration coefficient (0.179+0.186+0.19)/3 = 0.185 ns/channel (Is it okay to do that?).

Channel-to-TOF calibration coefficients used was 0.19 ns/channel. -peak positions were matched manually by cutting out the shift in the spectra w.r.t. Ref Det.

The following plot was drawn using upper plot and formula for calculation of asymmetry placed at [[1]]

Neutron part of spectrum

We should define how many peaks to use, i.e. we need some physical model for the process we observe.

Why do you want to fit multiple gaussians to the neutron distribution? TF


relations

In the calculation of it was used just integration of area under the curve instead of fitting neutron spectrum with three peaks (it was observed 0.36% difference between areas calculated in these two ways).

Summary tables for averaged over runs w/ polarized beam, and target

target Det A (side) Det C (side) Det A (up) Det C (up) Ref Det
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target Det A (side) Det C (side) Det A (up) Det C (up) Ref Det
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relation for and targets

Run(21/20), run(25/24) were taken 10/15/2008 and run(38/37), run(34/33) were carried out on 10/16/2008. Some beam conditions might have been changed.

target:

target

Where is gamma flash coming from? (H2O target)

(MT) = (Plastic shell)+(room BKG)

(H2O target) = (Plastic shell)+(H2O liquid)+(room BKG)

(H2O liquid) = (H2O target) - (MT)

(Plastic shell) = (MT) - (room BKG)

run# Duration, sec # of 's Rate (/sec) (MT) date 10/17/2008 NaI 122 (Det A up) 3071.69 27987.5 167.3 9.11 0.054 123 (Det C side) 3071.69 14227 119 4.63 0.038 124 (Ref Det) 3071.69 24037 155 7.8 0.05

run# Duration, sec # of 's Rate (/sec) (room BKG) date 10/17/2008 NaI 118 (Det A up) 1812.1 15873.5 125.9 8.76 0.069 119 (Det C side) 1812.1 7993 89 4.41 0.049 120 (Ref Det) 1812.1 14128 119 7.79 0.065

run# Duration, sec # of 's Rate (/sec) (H2O target(a)) date 10/17/2008 NaI 110 (Det A up) 1799.57 40725 202 22.63 0.11 111 (Det C side) 1799.57 11511 107 6.4 0.06 112 (Ref Det) 1799.57 18902 137 10.5 0.08

run# Duration, sec # of 's Rate (/sec) (H2O target(b)) date 10/17/2008 NaI 114 (Det A up) 1801.1 41351 203 22.96 0.11 115 (Det C side) 1801.1 11511 107 6.4 0.06 116 (Ref Det) 1801.1 18703 137 10.38 0.076

Separation of -sources:

run# rate(/sec) (room BKG) 118 (by Det A up) 8.76 0.069 119 (by Det C side) 4.41 0.049 120 (by Ref Det) 7.79 0.065

run# rate(/sec) (Plastic shell) 122-118 (by Det A up) 0.35 0.087 123-119 (by Det C side) 0.22 0.062 124-120 (by Ref Det) 0.029 0.082

run# rate(/sec) (H2O liquid (a)) 110-122 (by Det A up) 13.52 0.12 111-123 (by Det C side) 1.77 0.071 112-124 (by Ref Det) 2.67 0.094

run# rate(/sec) (H2O liquid (b)) 114-122 (by Det A up) 13.85 0.12 115-123 (by Det C side) 1.76 0.071 116-124 (by Ref Det) 2.56 0.091