Speaker
Description
After the discovery of the Higgs boson, one of the main target of particle physics is the measurement of the Higgs boson couplings to fermions and vector bosons. Furthermore, it is of great interest to measure the strength of the interaction of the Higgs boson with itself. In fact, through the Higgs field potential energy term, the Higgs boson can interact with itself at tree level. The coupling of this interaction is known as the Higgs boson self-coupling.
The self-coupling is very loosely constrained by EWK precision measurements therefore new physics effects could induce large deviations from its SM expectation.
The self-coupling can be measured directly using the Higgs boson pair production cross section, or indirectly through the measurement of the single-Higgs boson production and decays.
In this talk, first measurements of the Higgs boson self-coupling using single-Higgs production data and double Higgs production cross section measurements using the final states $\rm 4b$, $\rm b\bar{b}\tau^+\tau^-$ and $\rm b\bar{b} \gamma \gamma$ will be presented.
The results are obtained using ATLAS data corresponding to a luminosity of up to
80 fb$^-1$.