Exercise 7: Trigonometric functions

(15 minutes)

The quantity theta, or the angle that the beam makes with the z-axis, is calculated by:

\[ \theta = \arctan\left(\frac{p_{T}}{p_{z}}\right) \]

The units are radians. Revise your script to include a histogram of theta.

I’ll make your life a little easier

The math function you want is TMath::ATan2(y,x), which computes the arctangent of y/x. It’s better to use this function than TMath::ATan(y/x), because the ATan2 function correctly handles the case when x=0.

xkcd los_alamos — Figure 31: https://xkcd.com/809/ by Randall Munroe