Editing ROOT Analysis (section)

===Fitting the Graph===
The next step was to make a fit for the graph. Since the graph had the shape of the integral of the Gauss function, the erf function was chosen to model the data. In Root, another method was created to make a line of best fit that was made to model the erf function. To better approximate the data, the erf function was scaled to the range of the data. After the best fit function was displayed the first time, the chi squared value was too high. This was mostly due to the small error bars utilized by the program. So, then, by executing many trials for the same time interval, the range of the average round-trip time interval was determined.  The range of these means were approximately 0.05 seconds, so this was used as the length of the error bars. By using these error bars and the inputed data from above, the data and line of best fit was plotted on a graph as shown below.

====15.155 Meter Cable====


[[File:intervalfit.jpg|center|frame|Graph of time interval versus average round-trip time]]


====217 Meter Cable====

A possible fit may be a Heaviside function or a Step Function. But more importantly, the graph illustrates that our analysis at this cable length is not the best choice for this experiment. Since our expectation of a linear fit does not match our current experimental model, changes need to be made in order to better analyze the data.   


[[File:intervalfit_217.jpg|center|frame|Graph of time interval versus average round-trip time]]