Difference between revisions of "CDC signal integration new"
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− | Try to calculate dE/dx... | + | Try to calculate dE/dx by dividing by track length (calculated in the plane parallel to the endplates) and 3 methods: |
+ | (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" | ||
+ | |+(B) height of first maximum in signal amplitude / track length (unscaled) | ||
+ | |[[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_31810_maxampdx_unscaled.png|thumb|x180px|Tilted at 45 degrees, LV 3.0V, HV 2090V]] | ||
+ | |} | ||
+ | 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. | 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. | ||
{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
− | |+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) |
|[[Image:run_31809_integdx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | |[[Image:run_31809_integdx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | ||
|[[Image:run_31811_integdx.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | |[[Image:run_31811_integdx.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | ||
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{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
− | |+height of first maximum in signal amplitude / track length (scaled for tilt angle) | + | |+(B)height of first maximum in signal amplitude / track length (scaled for tilt angle) |
|[[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.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | |[[Image:run_31811_maxampdx.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | ||
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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 amplitude/track length histogram is 0.99 (old data) and 1.07 (new data). | ||
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{| border="0" cellpadding="2" | {| border="0" cellpadding="2" | ||
− | |+signal integrated from low threshold crossing to position of first maximum in signal amplitude / track length (scaled for tilt angle) | + | |+(C)signal integrated from low threshold crossing to position of first maximum in signal amplitude / track length (scaled for tilt angle) |
|[[Image:run_31809_intmax1dx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | |[[Image:run_31809_intmax1dx.png|thumb|x180px|No tilt, LV 3.0V, HV 2090V]] | ||
|[[Image:run_31811_intmax1dx.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] | |[[Image:run_31811_intmax1dx.png|thumb|x180px|Tilted at 30 degrees, LV 3.0V, HV 2090V]] |
Revision as of 16:08, 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) and 3 methods:
(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.
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