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Physics Constants in Sartre

Sartre provides a minimal set of constants but tools to easily access much more. More...

 #include "Constants.h"

Physics Constants

Detailed Description

The above constants are used throughout Sartre. They have global scope. More information can be easily accessed through the following tools:

• The EventGeneratorSettings class (a singleton) provide through its base class access to a lookup table of particle properties provided by ROOT. Here's an example:

                // In your Sartre application ...
                Sartre mysartre;
                mysartre.init("myRuncard.txt");
                
                EventGeneratorSettings *settings = mySartre.runSettings();
                
                // here it comes:
                TParticlePDG *part = lookupPDG(443);  // J/psi
                cout << "J/psi is my favorite particle:" << cout;
                cout << "mass = " << part->Mass() << " GeV" << endl;        
                // etc

There is a rich set of information reaching from spin, mass, decay channels etc available. See TParticlePDG documentation for more.

• Information on nuclei can be obtained through the Nucleus class. One Example:

                // In your Sartre application ...
                Sartre mysartre;
                mysartre.init("e_Au_Runcard.txt");
                
                Nucleus *myNucl = mySartre.nucleus();
                
                // Information about nucleus used
                cout << "Au is my favorite nucleus:" << cout;
                cout << "atomic mass = " << myNucl->atomicMass() << " GeV" << endl;        
                
                // You can of course always access information from other available nuclei:
                Nucleus big(208); // Pb
                cout << "Pb is larger than Au:" << endl;
                cout << "Pb radius = " << big.radius() << " fm" << endl; 
                cout << "Au radius = " << myNucl->radius() << " fm" << endl;