Getting to Higgs

Finding Evidence for W: W Transverse Mass Histogram
Data for 49,844 candidate W events are in an Excel spreadsheet with the following data as shown in the table below:

 

A

B

C

D

1

Run No

Event No
W TMass
GeV/c2
Bins

2

55237

19588

68.71732

 

3

55237

30799

72.19464

  
Get the data.
  1. Sort the data by ascending mass. Be sure to sort all the data in the first three columns!

  2. Make a histogram of the data.
    Rather than graphing the data as individual points, physicists group the data by mass. They consider the full range of the data and divide it into "bins" of equal range size. A histogram is a graph of the number of events in each bin vs. the bin range.

    They are looking for a peak in the data where most of the masses fall. This will be the value of the mass as detemined by that dataset, and the width of the distribution is a reflection of the errors in the measurements.

    Choose the size of bins that you think might give good results. You may have to bin your data several times based on what the histogram looks like. If your bins are too small, the data has too many peaks and valleys. If your bins are too large, you cannot see a peak. Excel will "bin" the data for you.

    When you create your histogram, you should see a new sheet with two columns similar to the table on the right.

    Bin

    Frequency

    45

    7

    50

    1595

    . . .

    . . .

    195

    0

  3. Plot frequency vs. binned momenta.
    Look for the peak in your data? Do you need to try a different size bin?
Help with data analysis.

References

Assignments: Identifying W