Difference between revisions of "CDC signal integration new"
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Try to calculate dE/dx by dividing by track length (calculated in the plane parallel to the endplates)... | Try to calculate dE/dx by dividing by track length (calculated in the plane parallel to the endplates)... | ||
(A) integrate signal for 700 ns (B) position of first max in amplitude (C) integrate signal up to position of first max in amplitude | (A) integrate signal for 700 ns (B) position of first max in amplitude (C) integrate signal up to position of first max in amplitude | ||
| + | |||
| + | {| border="0" cellpadding="2" | ||
| + | |+(A) integration from low threshold crossing for next 700ns / track length | ||
| + | |[[Image:run_31809_integdx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | ||
| + | |[[Image:run_31811_integdx_unscaled.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | ||
| + | |[[Image:run_31810_integdx_unscaled.png|thumb|x180px|Tilted at 45 degrees, LV 3.0V, HV 2090V]] | ||
| + | |} | ||
| + | |||
{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
| − | |+(B) height of first maximum in signal amplitude / track length | + | |+(B) height of first maximum in signal amplitude / track length |
|[[Image:run_31809_maxampdx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | |[[Image:run_31809_maxampdx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | ||
|[[Image:run_31811_maxampdx_unscaled.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | |[[Image:run_31811_maxampdx_unscaled.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | ||
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Ratio of vertical path lengths should be 1:1.16:1.45 | Ratio of vertical path lengths should be 1:1.16:1.45 | ||
| + | {| border="0" cellpadding="2" | ||
| + | |+(C)signal integrated from low threshold crossing to position of first maximum in signal amplitude / track length | ||
| + | |[[Image:run_31809_intmax1dx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | ||
| + | |[[Image:run_31811_intmax1dx_unscaled.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | ||
| + | |[[Image:run_31810_intmax1dx_unscaled.png|thumb|x180px|Tilted at 45 degrees, LV 3.0V, HV 2090V]] | ||
| + | |} | ||
| + | <div style="background-color:#ccf"> | ||
| + | Track length is calculated in the plane parallel to the endplates (no z information) so I scaled it by the tilt of the prototype for the 45 degree data, the upper cosmic trigger scintillator is high up enough that the cosmics are ~ vertical. (Purple background section has histograms from previous section with the tilted data scaled by 1/cos(tilt angle)) | ||
| − | |||
{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
|+(A) integration from low threshold crossing for next 700ns / track length (scaled for tilt angle) | |+(A) integration from low threshold crossing for next 700ns / track length (scaled for tilt angle) | ||
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|} | |} | ||
The ratio of tilted 45deg to horizontal MPV of Landau fitted to (integration to first maximum/tracklength) histogram is 1.07 (old data) and 1.18 (new data). | The ratio of tilted 45deg to horizontal MPV of Landau fitted to (integration to first maximum/tracklength) histogram is 1.07 (old data) and 1.18 (new data). | ||
| − | + | </div> | |
Revision as of 16:53, 9 July 2012
Cosmics, 50/50 gas, 2090V
Comparison with old (underpowered pream) data is at CDC_signal_integration
Run numbers are 31809 (horiz) 31810 (45 deg) and 31811 (30 deg) at 3.0V, 2.09kV
Ratio of fit MPV for horizontal : 30 degr : 45 degr data are 210 : 261 : 317 or 1 : 1.24 : 1.51 Ratio of vertical path lengths should be 1:1.15:1.41 or 1:1.16:1.45 after correcting for range of angles due to scintillator height and width.
Data below are for hit threshold 5 x pedestal sigma
Try to calculate dE/dx by dividing by track length (calculated in the plane parallel to the endplates)...
(A) integrate signal for 700 ns (B) position of first max in amplitude (C) integrate signal up to position of first max in amplitude
Ratio of fit MPV for horizontal : 30 degr : 45 degr data are 16.9 : 21.4 : 25.7 or 1 : 1.27 : 1.52 Ratio of vertical path lengths should be 1:1.16:1.45
Track length is calculated in the plane parallel to the endplates (no z information) so I scaled it by the tilt of the prototype for the 45 degree data, the upper cosmic trigger scintillator is high up enough that the cosmics are ~ vertical. (Purple background section has histograms from previous section with the tilted data scaled by 1/cos(tilt angle))
The ratio of tilted 45deg to horizontal integration means is 1.24 (old data) and 1.28 (new data); it should be 1 (as they are already scaled by track length) so this means the tilted integrations are 25-30% too large.
The ratio of tilted 45deg to horizontal MPV of Landau fitted to amplitude/track length histogram is 0.99 (old data) and 1.07 (new data).
The ratio of tilted 45deg to horizontal MPV of Landau fitted to (integration to first maximum/tracklength) histogram is 1.07 (old data) and 1.18 (new data).
Look at time over threshold...
Peak duration is # samples after the lower threshold crossing until the ADC value decreases by 2sigma over 2 samples, this is a measure of time over threshold in units of 8ns
