[FR] Example of non-trivial phi angle (four-body decay?) - Githubissues

KaiHabermann / decayangle

https://kaihabermann.github.io/decayangle/

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[FR] Example of non-trivial phi angle (four-body decay?) #37

Closed mmikhasenko closed 4 months ago

mmikhasenko commented 5 months ago

For arbitrary rotation one needs 3 angles (Euler angles), but in case of 3body, any Wigner rotation is just Ry(theta) Rz(psi). It would be good to find a case where one needs all three angles.

Consider a phase space point of B2psiKpipi. Get valid four vectors somehow (e.g. https://github.com/zfit/phasespace).
Compute Wigner rotations for ((1,2),(3,4)) with respect to (((1,3),2),4) for one of the particles.
report the case of non-trivial phi, theta, psi