Difference between revisions of "CDC prototype runs at CMU"

From GlueXWiki
Jump to: navigation, search
Line 60: Line 60:
 
root [6] prototype/cdc
 
root [6] prototype/cdc
 
(double)1.04723572482852867e+00
 
(double)1.04723572482852867e+00
 +
</pre>
 +
 +
<pre>
 +
root [0] Double_t prototype_observed_mpv = 204
 +
root [1] Double_t cdc_observed_mpv = 172
 +
root [2] prototype_observed_mpv/cdc_observed_mpv
 +
(double)1.18604651162790709e+00
 
</pre>
 
</pre>

Revision as of 20:27, 5 February 2015

The prototype runs at CMU were made with the prototype sitting along the top of one scintillator. The scintillator is only slightly larger than the prototype.
Run 2016 at JLab was a cosmics run with the BCAL trigger.
The CDC run at CMU used two scintillators in coincidence, the scintillators were above and below the CDC, separated by approx 2m, and are 9" wide and 6ft long. The cosmic rays would have been much closer to vertical than for the prototype and JLab measurements.The run data on this page (32990) were collected with the large paddles above and below the CDC, running along its length.

First article/prototype preamp & HVB were used for all but one of the prototype runs. One run was made using JLab preamp & HVB with all other settings unaltered since the previous run; as expected, the resulting data look very similar.


Prototype, 2100V, 50/50 Ar/CO2
max amp
drift time
Prototype, 2100V, 55/45 Ar/CO2
max amp
drift time
Prototype, 2100V, 55/45 Ar/CO2 JLab electronics
max amp
drift time
Prototype, 2100V, 60/40 Ar/CO2
max amp
drift time
CDC straw 496 2100V JLab run 2016 (cosmics, BCAL trigger)
max amp
drift time
CDC (sum) 2100V JLab run 2016 (cosmics, BCAL trigger)
max amp
drift time
CDC (72ch) at CMU, 2100V, 50/50 Ar/CO2 with large scint paddles along the length of the CDC
max amp
drift time w terrible fit


CDC at CMU had MPV at ~190 for 2110V, 50/50 Ar/CO2.

CDC wire is 20um and straw radius is 0.77cm, prototype wire is 17.8um (7 mil), and prototype straw radius is 0.79375cm.

from Blum & Rolandi
root [4] Double_t prototype = 1.0/log((Double_t)0.79375/(Double_t)17.8)
root [5] Double_t cdc = 1.0/log((Double_t)0.77/(Double_t)20.0)
root [6] prototype/cdc
(double)1.04723572482852867e+00
root [0] Double_t prototype_observed_mpv = 204
root [1] Double_t cdc_observed_mpv = 172
root [2] prototype_observed_mpv/cdc_observed_mpv
(double)1.18604651162790709e+00