Searching for<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>t</mml:mi><mml:mo>→</mml:mo><mml:mi>c</mml:mi><mml:mi>h</mml:mi></mml:math>with multileptons

The results of a multilepton search conducted by the CMS collaboration with $5\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of data collected from 7 TeV $pp$ collisions are used to place the first bound on the rare flavor-changing decay of the top quark to a Higgs boson and charm quark. Combining results from a number of exclusive three- and four-lepton search channels yields an estimated upper limit of $\mathrm{Br}(t\ensuremath{\rightarrow}ch)&lt;2.7%$ for a Higgs boson mass of 125 GeV. The sensitivity of future dedicated searches for $t\ensuremath{\rightarrow}ch$ could be improved by adding exclusive same sign dilepton channels, as well as by subdividing channels based on $b$-quark tagging and partial kinematic top quark and Higgs boson tagging. This bound may be interpreted more widely within a range of new physics processes that yield final states with a $W$-boson in association with a Higgs boson. For such processes with kinematics that are similar to top-anti-top production and decay, the estimated limit on cross section times branching ratio corresponds to roughly $\ensuremath{\sigma}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{Br}(pp\ensuremath{\rightarrow}WhX)&lt;9\text{ }\text{ }\mathrm{pb}$.