# Getting to Higgs

## Finding Evidence for W: Z Mass Histograms

Data for 2,012 candidate Z events are in an Excel spreadsheet with the following data as shown in the table below:

1. Z TMass = Z transverse mass or Z mass in a 2-dimensional x-y plane perpendicular to the beam pipe

2. Z Mass = Z mass calculated from all three dimensions of momenta
 A B C D E F 1 Run No. Event No. Z TMassGeV/c2 Z MassGeV/c2 Bin Z MT Bin Z M 2 63977 63165 54.40164 70.40511 3 67642 17809 55.24385 87.24314
We will use this information to determine a correction factor for the W transverse mass based on these Z mass datasets.

To find the W correction factor, we begin by graphing the two Z mass values from our data:

1. Bin the data for each of the two masses.

2. Make two histograms of the binned masses, one for the transverse mass and one for the mass.

3. Plot frequency vs. binned masses for each.
Help with data analysis.

What do the histograms tell us?

1. Read the peaks on the histograms and record the Z transverse mass and the Z mass from these datasets.

2. Calculate the W mass correction factor, the ratio of the masses (Z Mass)/(Z TMass).

3. Calculate the W mass: multiply the W transverse mass by the correction factor.

4. Compare your values for W and Z with those in the Particle Data Book. Explain.