Log 6.2 - Oct 17, 2019

Copied code for calorimeter problem.

Fixed errors:

    put missing bracket at end - then moved to before functions for histogram to make it more efficient

    changed secretparameters.txt to secretparameters.tx to fit with file name

Complied and ran code.

In Class:

'g' means global

true: without randomness

Google "ROOT gRandom->Rndm()" and find what Rndm() function does. ?

    Machine Independent Random number generator

    Generates num between 0 and 1

    Lower random bit are correlated - Not useful for statistical study

Add another histogram for transverse momentum (p_T = sqrt(P_x^2 + P_y^2)

Added 2nd histogram - got help from classmate to make it work

Questions for calorimeter Problem:

Set N=1 and run it.  From this "data", what would you guess the mass of the mother particle is?  And, how far would you guess the true mother mass could be from this measured value? 

The "data" suggests that the mother particle's mass is around 108. Running the program again gives masses of 75, 88, and 86, so it seems that the actual mother mass would be around 30 away from the predicted.

Now change N to 10.  What do you find? 

The distribution is now centered around 85, and appears to fall on the lower end.

Change N to 100?  What do you find? 

The distribution is now focused around about 90 and slightly above.

Change N to 1000.  What do you find? 

The distribution is now more normal centered around 90.

Now open secretparameters.txt and change the first number in it to 1.  Repeat with N=1,10,100,1000.  What have you learned?

After changing the parent mass from 91 to 1, the distribution appears to be centered around 10 (but the full chart is not visible). This seems to show that for low parent masses this program will give estimations that are higher.