Speaker
Description
Standard Model of high energy physics is very successful, but neutrino sector is not completely accommodated into it (e.g. neutrino oscillations). One of the possible solution is introduction of heavy sterile neutrino, which does not have any flavour and interacts with only flavour SM neutrinos via oscillations.
In this talk studies of heavy sterile neutrino N is presented, where neutrino originates from $D_s^+$ decay, namely $D_s^+ \to \mu^+ N \to \mu^+ \mu^+ \pi^-$. Origin of $D_s^+$ mesons are semileptonic decays $B_s^0 \to D_s^+ \mu^- \mu_\nu$. Studies are provided using Monte-Carlo simulation samples with CMS detector at CERN Run-2 conditions (proton-proton collisions with $\sqrt{s} = 13$ TeV). Full simulation (Pythia + EvtGen + Photos + Geant4) is provided, as well as the full reconstruction of the simulated decay. Several points on ($m_N, V_{N\mu}$) plane are generated for the sterile neutrino properties, where $m_N$ and $V_{N\mu}$ are the expected mass of N and coupling parameter with mass. We provide studies of kinematic and topological variables of the involved particles, reconstruction efficiencies in dependence of N properties, detector resolution and selection criteria, fit functions etc.
The obtained results and estimated sensitivity in ($m_N, V_{N\mu}$) plane will be used for the future search for this decay and heavy sterile neutrino, using real CMS Experiment data.
