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==Fitting the Position of Each Bundle Support Mounting Rod to a Straight Line==
 
==Fitting the Position of Each Bundle Support Mounting Rod to a Straight Line==
 
At this point the exact location for each bundle support rod is known. These locations place the scintillating fibers of each bundle support at their optimal location. Unfortunately these locations deviate slightly from a straight line. To correct this deviation and find a compromise the their location that's within the TAGM required tolerance, we must use ROOT and fit a first order polynomial to the calculated locations. A template C++ file [http: (TAGM_8GeV_Bundle_Rod_Fit.C)] has been written for this purpose. Once the arrays used for the rods' x and y locations are updated for the desired tagging energy spectrum, then the macro can be run or the code can be copy & pasted directly into ROOT's command line. The generated histograms, for the forward and rear rods, can then be fitted to a first order polynomial (pol1) using the Fitting Tool. Several fit equations are already recorded in a text file [http (TAGM_Weights.txt)]. The fits are then utilized back in the Excel file to determine the "Y-Fit" location for each rod X location. This way the parallel rails can be orientated based on these numbers and the three rail components required for the TAGM move can be designed.
 
At this point the exact location for each bundle support rod is known. These locations place the scintillating fibers of each bundle support at their optimal location. Unfortunately these locations deviate slightly from a straight line. To correct this deviation and find a compromise the their location that's within the TAGM required tolerance, we must use ROOT and fit a first order polynomial to the calculated locations. A template C++ file [http: (TAGM_8GeV_Bundle_Rod_Fit.C)] has been written for this purpose. Once the arrays used for the rods' x and y locations are updated for the desired tagging energy spectrum, then the macro can be run or the code can be copy & pasted directly into ROOT's command line. The generated histograms, for the forward and rear rods, can then be fitted to a first order polynomial (pol1) using the Fitting Tool. Several fit equations are already recorded in a text file [http (TAGM_Weights.txt)]. The fits are then utilized back in the Excel file to determine the "Y-Fit" location for each rod X location. This way the parallel rails can be orientated based on these numbers and the three rail components required for the TAGM move can be designed.
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<gallery caption="Fitting the calculations to real life" widths="450px" heights="450px" class="center">
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  Fwd_Rod_8GeV.png|Figure 2: Histogram of the bundle supports' forward rod position (*) in focal plane coordinates. The red line is a first order polynomial fit (pol1) using the ROOT fitter.
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  Rear_Rod_8GeV.png|Figure 3: Histogram of the bundle supports' rear rod position (*) in focal plane coordinates. The red line is a first order polynomial fit (pol1) using the ROOT fitter.
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</gallery>
     
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