The stransverse mass MT2

[Najimuddin Khan]

Hi,
Is it possible to calculate the transverse mass MT2 using the standard variables in the Delphes program? Any suggestion !!!!

Thanks and regards,
Najim

[Pavel Demin]

I think that it could be calculated using the Mt2() method of the TLorentzVector class. Most of the Delphes classes have a method called P4() that returns an object of the TLorentzVector class.

For example, the following code should work for a jet:

  Double_t mt2 = jet->P4().Mt2()

[Najimuddin Khan]

Hi,
I think it (the stransverse mass MT2) is not the same as in REFs:
Chris Lester, David Summers Phys.Lett.B463:99-103,1999
Alan Barr, Christopher Lester, Phil Stephens J.Phys.G29:2343-2363,2003

Am I missing anything?

[Pavel Demin]

Am I missing anything?

What is missing is a detailed description of what you're looking for.

[Najimuddin Khan]

Hi,
Thank you so much for the reply.
I have two charged lepton (coming from W+W- or some BSM particles but not from the Z) plus missing ET in the final state.
I want to calculate the stransverse mass MT2 variable(see equation (8) of ​http://iopscience.iop.org/article/10.1088/0954-3899/29/10/304/pdf). The authors have used some maximization and minimization procedure using different codes.

Is this code available inside the Delphes or I have to introduce it by hand?
Is it same as you suggested in your earlier reply?: Double_t mt2 = jet->P4().Mt2()

Thank you
NK

[Pavel Demin]

I don't have access to the full text linked article.

Anyway, if the variable that you're looking for is calculated from the kinematic parameters of several selected objects (lepton, missing ET, etc), then I think that it should be calculated in the code that analyses the Delphes output.

So, the short answer is that the code isn't available inside Delphes and you have to introduce it by hand.