DC Binning Based On Wire Numbers

From New IAC Wiki
Jump to navigation Jump to search
[math]\textbf{\underline{Navigation}}[/math]

[math]\vartriangleleft [/math] [math]\triangle [/math] [math]\vartriangleright [/math]

DC Binning Based on Wire Numbers

The bin size based on wire number will need to be a uniform width of 1, as in an increment of 1 between the integer values of the wires. This uniformity in bin size based on wire numbers is not uniform when viewed by the angle theta due to the Drift Chamber geometry discussed earlier.

Modifying evio2root.cc


Layer1bins.png
Layer1bins Isotropic.png


The corresponding theta scale can be superimposed over the bin plot using the minimum and maximum angles


[math]\theta_{min}=5.23^{\circ}\ \ \ \theta_{max}=41.07^{\circ}[/math]


We will use the polynomial fit for the expression of theta as a function of the wire number

[math]\theta_{n}=4.93253 +0.297371 n+0.000566298 n^2-3.04016*10^{-6} n^3[/math]


gStyle->SetStripDecimals(kTRUE);
TF1 *fit_function=new TF1("fit_function","[0]+[1]*x+[2]*x*x+[3]*x*x*x",5.23,41.07);
fit_function->SetParameters(4.93253,0.297371,0.000566298,-.00000304016);
TGaxis *A1 = new TGaxis(0,5000,113,5000,"fit_function",510,"-");
A1->SetTitle("Angle Theta(degrees)");
A1->Draw();


Layer1binWeighted.pngMolThetaLabWeighted.png


Layer1binWeighted Isotropic.pngMolThetaLabWeighted2.png

Using the expression for n in terms of Theta:

[math]n = \frac{-957.412}{\tan{ \theta}+2.14437}+430.626[/math]


This relationship can be used to multiply each Moller Scattering angle theta in the lab frame, with it's differential cross-section weight, to find the Moller differential cross-section as a function of wire number in the lab frame.


MolThetaWireWeighted.pngMolThetaWireWeightedIsotropic.png


MolThetaWireWeightedAdjusted.pngMolThetaWireWeightedAdjustedIsotropic.png


TheoryDCbinsWire.pngTheoryDCbinsWireIsotropic.png




[math]\textbf{\underline{Navigation}}[/math]

[math]\vartriangleleft [/math] [math]\triangle [/math] [math]\vartriangleright [/math]