Lorentz Boost

Newbie
1

If I remember well, a good class TLorentzVector was previously in ROOT. Using it one could easily do boosts to some other frames like:

TLorentzVector v;
v.Boost(bx, by, bz);

Now instead of this user-friendly class the Reference Guide suggest to use two independent classes ROOT::Math::PxPyPzEVector and ROOT::Math::Boost with zero information on how to use them together. Moreover, the ROOT::Math::Boost class seems to be broken.

ROOT::Math::Boost b(bx, by, bz);
$ undefined reference to `ROOT::Math::Boost::SetComponents(double, double, double)'

So, what is now the procedure of boosts to another frame? If there is a working method or it’s better to still use the old TLorentzVector class?

2

You need to link your utility against: -lGenVector

3

Thank you, but the main question was about boosts.
So now with the new ROOT::Math::LorentzVector and ROOT::Math::Boost classes it’s obsolete and one should use the old TLorentzVector class (or to write it’s own functions)?

4

TLorentzVector

5

Actually, I found this by myself.
One needs to construct another vector:

      ROOT::Math::PxPyPzEVector p(px, py, pz, e);
      ROOT::Math::Boost b(bx, by, bz);
      ROOT::Math::PxPyPzEVector p2=b(p);

Better to have it in the ref. guide.