More about strange charged trilepton events

I already told about indications for strange charged tri-lepton events at CMS. The inspiration came from a posting CMS sees SUSY-like tri-lepton excesses of Lubos.

Only a few days later both Tommaso and Lubos discussed a quite recent paper telling about charged tri-lepton events observed at CMS.

1. From Tommaso's posting one learns that three charged leptons with total mass near to Z⁰ mass have been observed. Charge conservation of course requires fourth charged lepton if the particles originate in the decay of Z⁰ as assumed and Tommaso argues that this lepton has so low energy that it is not detected. This kind of lepton could results in an energy asymmetric decay of photon. The assumption that Z⁰ is the decaying particle might be however un-necessarily strong: it could be quite well W with almost the same mass. In this case charge conservation allows genuine charged tri-lepton event. The discussion of my earlier posting suggests the decay W→ sW+sZ to be the source of charged tri-lepton events.

2. The authors of the paper propose that the reaction could be initiated by a decay of squark or gluino and necessarily involving R-parity breaking. There are two possibile options for R-parity breaking allowed by proton stability depending on whether it conserves lepton or baryon number. For lepton number violating option intermediate particle is neutralino (lightest sparticle which is stable in R-parity breaking scenarios ) and for baryon number violating scenatior bino or higgsino. The R-parity violating decay of lightest spartner (neutral) would yield slepton-lepton pair and the R-parity violating decay of slepton a lepton pair plus neutrino. This would produce instead single observed lepton charged tri-lepton state. The authors do not give enough details to make possible for a non-professional to deduce what the detailed model for the process really is.

It is interesting to consider the situation in TGD framework in light of the crucial additional data (the three charged leptons have mass rather near to that of Z⁰ and therefore to that of W).

1. The decay of W → sW +sZ with the decays sW and sZ proceeding in either of the two manners discussed in the previous posting would predict that the total mass of all particles produced is near to W mass (and therefore Z mass) and also why one obtains genuine charged tri-lepton states. The problem is that missing energy in the form of neutrinos and neutral sparticles is present and it is not at all clear why this energy should be small.

2. An option not discussed discussed in the previous posting is the decay W→ sν+L followed by the decay sν→ L+sW followed by sW→ L+sν would not break R-parity and would produce sν. Total energy would correspond to W mass but it is not clear why the missing energy assigned with sν should be small.

3. R-parity violation predicted by TGD however allows also to consider the direct decay sνrarr; L⁺+L^- so that there would be no missing energy. One could say that the decay is the reversal of a process in which L⁺+L^- annihilates to a sν identifiable as a pair of neutrino and right-handed neutrino at microscopic level. All standard model quantum numbers would be conserved.

In TGD framework R-parity violation is a prediction of the theory and it would not violate either baryon or lepton number conservation. There is no need to assume undetected charged lepton since charge conservation allows charged tri-lepton final state as such without any missing energy. Obviously the TGD based model is by several orders of magnitude simpler than the model based on standard SUSY.

For details and background see the chapter New particle physics predicted by TGD: part I of "p-Adic Length Scale Hypothesis and Dark Matter Hierarchy".