V. Botta

This poster presents a measurement of the associated production of the Higgs boson ($H$) with a top quark anti-quark pair ($t\bar{t}H$) or a single top quark ($tH$) in the final state where the Higgs boson decays to a bottom quark anti-quark pair. Data from proton-proton collisions at a center-of-mass energy of 13\;TeV corresponding to an integrated luminosity of 138\;fb$^{-1}$ and collected by the CMS experiment at the CERN LHC between 2016 and 2018 are analysed. The observed inclusive $t\bar{t}H$ production rate relative to the standard model (SM) expectation is $0.33\pm0.26$, and a differential measurement as a function of the Higgs boson transverse momentum $p_T$ is also performed. An upper limit on the $tH$ production rate of 14.6 times the SM expectation is set at the 95\% confidence level, with an expectation of 19.3$^{+9.2}_{-6.0}$. Finally, constraints are set on the strength and $CP$ structure of the coupling between the Higgs boson and the top quark.

The Compact Muon Solenoid (CMS) detector is a multi-purpose detector constructed in order to study high-energy particle collisions at the Large Hadron Collider (LHC) at CERN.The all-silicon design of the tracking system of the CMS experiment provided excellent resolution for charged tracks and an efficient tagging of jets during Run 1 and Run 2 of the LHC.After the pixel detector of the CMS experiment was upgraded and installed during the shutdown in the beginning of 2017, the positions and orientations of the tracker modules needed to be determined with a precision of several micrometers.The alignment also needs to be quickly recalculated each time the state of the CMS magnet is changed between 0 T and 3.8 T. The latest results of the CMS tracker performance in the 2017 run are presented, with a special focus on alignment and resolution performance using several million reconstructed tracks from cosmic rays and collision data.

The most recent search for the Standard Model Higgs boson decaying to a pair of $\tau$ leptons is performed using proton-proton collision events at a centre-of-mass energy of 13 TeV, recorded by the CMS experiment at the LHC. The full 2016 dataset, corresponding to an integrated luminosity of $35.9~fb^{-1}$, has been analysed. The Higgs boson signal in the $\tau^{+}\tau^{-}$ decay mode is observed with a significance of 4.9 standard deviations, to be compared to an expected significance of 4.7 standard deviations. This measurement is the first observation of the Higgs boson decay into fermions by a single experiment.

The most recent measurements of the Higgs H(125) boson in several final states, including decays to bosons, fermions, and the associated production of a Higgs boson with top quarks, are reviewed. Results have been obtained analysing the protonproton collision data collected with the CMS detector at the Large Hadron Collider (LHC) in 2016, corresponding to an integrated luminosity of 35.9 fb -1 at a centre-of-mass energy of 13 TeV.