C++ top tips #1

C++ Namespaces:

Should use std namespace for cout etc eg:

std::cout << "Output via std::cout" << std::endl;

and not

cout << "Regular cout output" << endl;

Namespaces can be created by:

namespace simon { class simonsclass { }; void simonsfunction { } }

Questions, ideas and plans

The current status of code is that events with 2 or more jets are reconstructed and interesting quantities (eta etc) are placed in ROOT histograms. This is not especially useful for analysis as quantities are not linked (cutting, in ROOT, makes no sense). However it does give us a useful sanity check. I will try and get Kajari to run the codes over each of our signal datasets. It might also be useful (as another sanity check) to plot some MEt/lepton information. It may be senseible to put a soft cut on jet energy at 20-30Gev.

The current plan is to use ORCA solely to reconstruct events, and ROOT to apply cuts/do the
analysis. This gives us more flexibility in tuning cuts etc. It also means we need to store interesting events as objects (inherit from TObject) containing Jets, Leptons and Missing Et. I'm currently planning on having 4 classes:

MyEvent

Inheritted from TObject (or prehaps the ROOT Event object), basically as a holder for the other three classes. We will store in a ROOT tree one MyEvent per interesting event (obviously). Will be made of a MyMET object and arrays of MyJet and MyLepton. The arrays will hold one object per jet/lepton in the event.

MyJet

Will contain (at least) jet mass & energy, Et, eta, the Lorentz vector, the algorithm and RecQuery used to reconstruct the event and the calo towers that make up the event.

MyLepton

Will contain charge, type (muon/electron - unless these are stored as two separate objects), and how they were reconstructed (calo towers, dt/csc hits)

MyMET

Stores the algorithm and RecQuery used to reconstruct the MET, it's magnitude and the phi-direction

Questions:

1. HLT path - how do we write our own?


2. L1 trigger and HLT - how do we put our events through these?


3. Signal & Background - how do we add background to the signal


4. QCD background - where is it? how do we use it?


5. How are leptons reconstructed? Will we need an electron and muon object?