Difference between revisions of "Wire angle correspondance"
Line 27: | Line 27: | ||
=CED Verification= | =CED Verification= | ||
Using CED to verify the angle and wire correlation, | Using CED to verify the angle and wire correlation, | ||
− | + | ||
Zooming in on the view paralell to the direction of the wires in ced, we can examine the wire corresponding theta angle in the drift chamber. | Zooming in on the view paralell to the direction of the wires in ced, we can examine the wire corresponding theta angle in the drift chamber. | ||
Line 89: | Line 89: | ||
+ | ==Super Layer 1:Layer 1== | ||
+ | |||
+ | Finding the difference between wires 1 and 2, | ||
− | + | <center><math>5.09-4.79=.3^{\circ} \frac{\pi\ radians}{180^{\circ}}=0.005235987756\approx\ 0.00524\ radians</math></center> | |
− | + | Examing a hit at layer 1, wire 112 we find the corresponding angle theta in the lab frame to be 40.82 degrees | |
− | |||
− | |||
This sets the lower limit: | This sets the lower limit: | ||
− | <center><math>\frac{4. | + | <center><math>\frac{4.79^{\circ}}{1}\frac{\pi\ radians}{180^{\circ}}=.083601271171\ radians\approx 0.0836\ radians</math></center> |
This sets the upper limit: | This sets the upper limit: | ||
− | <center><math>\frac{40. | + | <center><math>\frac{40.82^{\circ}}{1}\frac{\pi\ radians}{180^{\circ}}=.712443400664\ radians\approx 0.712\ radians</math></center> |
Taking the difference, | Taking the difference, | ||
− | <center><math>. | + | <center><math>.712443400664-.083601271171\approx\ .629\ radians</math></center> |
Dividing by 112, we find | Dividing by 112, we find | ||
− | <center><math>\frac{. | + | <center><math>\frac{.628842129493}{112}=.00561466187\ radians\approx\ 0.00561\ radians</math></center> |
===Changing cell size=== | ===Changing cell size=== | ||
Noting the difference from the spacing for a single cell, to the entire detector layer | Noting the difference from the spacing for a single cell, to the entire detector layer | ||
− | <center><math>0. | + | <center><math>0.00524-0.00561=0.00037\ \approx .001\ radians</math></center> |
Determining by how much each increment between each wire's corresponding angle must deviate from the starting distance between wires to the end of the wires: | Determining by how much each increment between each wire's corresponding angle must deviate from the starting distance between wires to the end of the wires: | ||
− | <center><math>\frac{0. | + | <center><math>\frac{0.00037\ radians}{112\ wires}=4\times 10^{-2} \frac{radians}{wire}</math></center> |
Revision as of 16:31, 28 November 2016
Determining wire-theta correspondance
To associate the hits with the Moller scattering angle theta, the occupancy plots of the drift chamber hits by means of wire numbers and layer must be translated using the physical constraints of the detector. Using the data released for the DC:
DC: Drift Chambers(specs)
This gives the detector with a working range of 5 to 40 degrees in Theta for the lab frame, with a resolution of 1m radian.
This sets the lower limit:
This sets the upper limit:
Taking the difference,
Dividing by 112, we find
CED Verification
Using CED to verify the angle and wire correlation,
Zooming in on the view paralell to the direction of the wires in ced, we can examine the wire corresponding theta angle in the drift chamber.
Corresponding theta angles can be found for other wires, in Region 1, Superlayers 1 and 2.
Wire Number | Layer 1 | Layer 2 | Layer 3 | Layer 4 | Layer 5 | Layer 6 |
---|---|---|---|---|---|---|
1 | 4.79 | 5.03 | 4.98 | 5.22 | 5.16 | 5.40 |
2 | 5.09 | 5.33 | 5.27 | 5.51 | 5.45 | 5.69 |
78 | 29.79 | 29.93 | 29.74 | 29.88 | 29.69 | 29.83 |
111 | 40.50 | 40.59 | 40.36 | 40.44 | 40.21 | 40.29 |
112 | 40.82 | 40.90 | 40.67 | 40.75 | 40.52 | 40.60 |
Super Layer 1:Layer 1
Finding the difference between wires 1 and 2,
Examing a hit at layer 1, wire 112 we find the corresponding angle theta in the lab frame to be 40.82 degrees
This sets the lower limit:
This sets the upper limit:
Taking the difference,
Dividing by 112, we find
Changing cell size
Noting the difference from the spacing for a single cell, to the entire detector layer
Determining by how much each increment between each wire's corresponding angle must deviate from the starting distance between wires to the end of the wires:
An uncertainty of this magnitude in radians corresponds to an angular uncertainty of
Testing this for a random angle, 78 degrees we find
Adding this to the starting angle of 4.91 degrees
Comparing this to CED at wire 78
Super Layer 1:Layer 2
For a hit at layer 2, wire 1 we find the corresponding angle theta in the lab frame to be 5.00 degrees
Examing a hit at layer 2, wire 112 we find the corresponding angle theta in the lab frame to be 41.05 degrees
This sets the lower limit:
This sets the upper limit:
Taking the difference,
Dividing by 112, we find
Super Layer 1:Layer 6
For a hit at layer 6, wire 1 we find the corresponding angle theta in the lab frame to be 5.30 degrees
Examing a hit at layer 6, wire 112 we find the corresponding angle theta in the lab frame to be 40.61 degrees
This sets the lower limit:
This sets the upper limit:
Taking the difference,
Dividing by 112, we find
Superlayer 2:Layer 1