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 2 years ago  

There is an irreducible background coming from the Standard Model (neutrinos), as well as an instrumental background coming from the non perfect identification efficiency of the detectors. For the moment, all measurements of a 'missing momentum signal' are compatible with the above expectation. In other words, we measure some momentum imbalance, but this is well explained by the Standard Model and experimental effects. For instance, let's take the image below from the CMS collaboration of the LHC.


[Credits: PRD 97 (2018) 092005 (CC BY 4.0)]

It shows the transverse energy imbalance obtained in certain collisions. Data (black dots) agrees very well with the Standard Model expectation (the sum of the coloured histograms). A potential signal should materalise as an excess on this curve, that is not seen.

Ok, thank you very much for taking the time to explain this.

Much appreciated!

 2 years ago  

You are very welcome! The pleasure was mine :)