Measurement of the production of charm jets tagged with D${}^0$ mesons in pp collisions at $\sqrt{s}$= 7 TeV

The production of charm jets in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=7$ TeV was measured with the ALICE detector at the CERN Large Hadron Collider. The measurement is based on a data sample corresponding to a total integrated luminosity of $6.23$ ${\mathrm{n}\mathrm{b}}^{-1}$, collected using a minimum-bias trigger. Charm jets are identified by the presence of a D${}^0$ meson among their constituents. The D${}^0$ mesons are reconstructed from their hadronic decay D${}^0\to$K${}^{-}{\pi }^{+}$. The D${}^0$-meson tagged jets are reconstructed using tracks of charged particles (track-based jets) with the anti-$k_{\mathrm{T}}$ algorithm in the jet transverse momentum range $5<p_{\mathrm{T},\mathrm{j}\mathrm{e}\mathrm{t}}^{\mathrm{c}\mathrm{h}}<30$ $\mathrm{G}\mathrm{e}\mathrm{V}\mathrm{/}c$ and pseudorapidity $\mathrm{\mid }{\eta }_{\mathrm{j}\mathrm{e}\mathrm{t}}\mathrm{\mid }<0.5$. The fraction of charged jets containing a D${}^0$-meson increases with $p_{\mathrm{T},\mathrm{j}\mathrm{e}\mathrm{t}}^{\mathrm{c}\mathrm{h}}$ from $0.042 \pm 0.004, $(\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t})$ \pm 0.006, $(\mathrm{s}\mathrm{y}\mathrm{s}\mathrm{t})$$to$0.080 \pm 0.009, \rm{(stat)} \pm 0.008, \rm{(syst)}$\mathrm{.}ThedistributionofD$^0$-meson tagged jets as a function of the jet momentum fraction carried by the D${}^0$ meson in the direction of the jet axis ($z_{\mathrm{\mid }\mathrm{\mid }}^{\mathrm{c}\mathrm{h}}$) is reported for two ranges of jet transverse momenta, $5<p_{\mathrm{T},\mathrm{j}\mathrm{e}\mathrm{t}}^{\mathrm{c}\mathrm{h}}<15$ $\mathrm{G}\mathrm{e}\mathrm{V}\mathrm{/}c$ and $15<p_{\mathrm{T},\mathrm{j}\mathrm{e}\mathrm{t}}^{\mathrm{c}\mathrm{h}}<30$ $\mathrm{G}\mathrm{e}\mathrm{V}\mathrm{/}c$ in the intervals $0.2<z_{\mathrm{\mid }\mathrm{\mid }}^{\mathrm{c}\mathrm{h}}<1.0$ and $0.4<z_{\mathrm{\mid }\mathrm{\mid }}^{\mathrm{c}\mathrm{h}}<1.0$, respectively. The data are compared with results from Monte Carlo event generators (PYTHIA 6, PYTHIA 8 and Herwig 7) and with a Next-to-Leading-Order perturbative Quantum Chromodynamics calculation, obtained with the POWHEG method and interfaced with PYTHIA 6 for the generation of the parton shower, fragmentation, hadronisation and underlying event.