Developing Code for Analysing the 2014 data
Here is a ntuple ... loop through the events and make plots.
- A 2014 ntuple, 1410420649complete.root, can be downloaded from Google drive CERN BL4S 2015 - Winning Teams.
- Create a folder just for this application
- Here is the MyClass.C and the MyClass.h for this tuple ... produced as described in the section of the ROOT UserGuide on Trees ... using TTree::MakeClass.
- Here is a skeleton main programme Analyse-2014-data.cpp, developed from MyClass.C, but containing a main function and showing how to fill a histogram by looping over events.
- Use this Makefile
- Put all of this in the same folder (Analyse-2014-data.cpp, the 2014 data, MyClass.h and the Makefile) ... then make.
Exercises
- Add conditions to the filling of the histogram for the Lead Glass Spectrum .... for example, based on the Cerenkov signal and the hit positions in the DWC.
- You should see the peak in th calorimeter becomes both cleaner and has less statistics as the correct filters are applied. There is a pay-off between good filtering and losing too many events (filters are not 100% effective).
- Fit the peak in the Lead Glass Spectrum, once with a Gaussian, using the Fit Panel, and once with a Lorentzian, defined within your program.
- The work done with "FittingDemo.C" from the tutorial/fit folder can inspire you here.
- You can also play with adding polynomial backgrounds, of different orders, and also using different fit strategies (fixing parameters, fitting, releasing parameters, fitting, different algorithms for the fit ... and so on ...)
Natures preference .... the "R" ratio ... Pion decay to electrons as compared to muons
- Read and understand the ATHENS 2014 proposal here.
- Get the data for this experiment, pion beams of 4, 7, 10 GeV available on the teams Google Drive
- You can also get a description of the ntuple at the same place.
- Now make a fresh folder for this analysis, and import your Makefile, MyClass.h and the c++ analysis app ... all in this directory.
- Now read back the tuple, and count separately the number of electrons and muons from pion decay.
- You apply the correct cuts / filters in the Cherenkovs and the first two scintillators, and then the resulting particles are likely to be pions only.
- You ask the calo to be > 1/2 E_beam to select for an electron
- You ask the third scintillator to fire for a muon
- Now make the "R" ratio
- Histogram from Brandon's MBP 2 for 10GeV data 10GeV Muon vs. Positron Histogram
- Complete Analysis from Brandon's MBP 2
- Representation of experimental components from Brandon's MBP 2: here.
- Program for using DWC DWC program.cpp
