Two questions about the Higgs decay mode graph I have two questions reading this graph which shows the Higgs decay mode:

I know the mass of Higgs bosons is measured to be around 125 GeV, which is the solid line on the graph, so I wonder why could the mass on the x-axis become other values other than the measured results, and why are we interested in different Higgs masses?
Another question is why there's no data for the Higgs decay into 4 leptons, on the graph?
Thanks for the help!
 A: Based on the date (2013), I assume this figure was made before the Higgs was discovered or its mass was published. The curves are based on a theoretical calculation of the various branching ratios as a function of the Higgs mass within the Standard Model. If the branching ratios are also measured then this would be a way to measure the Higgs, or at least one can check the consistency of the measured Higgs mass and branching ratios, with the Standard Model prediction.
There is not a direct coupling between the Higgs and 4 leptons in the Standard Model. I believe the decay process you have in mind is $H\rightarrow ZZ \rightarrow 4\ell$ (Higgs decays to two $Z$ bosons which decay to a set of 4 leptons, either electrons or muons). (As @joseph h mentions in the comments, there are also other decay modes that lead to 4 leptons, like $H\rightarrow WW \rightarrow 4\ell$ and $H\rightarrow t\bar{t}\rightarrow 4\ell$). The four leptons are stable enough to be directly detected. However, I believe this plot is showing direct decays of the Higgs into other particles, ignoring the future decays that will occur before the final products are seen in a detector.
I can't be 100% sure about what message this plot was intended to send without additional context, though (like, what paper was it published in).
