Flavor dependence of jet quenching in $pp$ collisions and its effect on the $R_{AA}$ for heavy mesons

We study the flavor dependence of the medium modification factor $R_{pp}$ for $pp$ collisions for scenario with formation of a small-size quark-gluon plasma (QGP) for RHIC ($\sqrt{s}=0.2$ TeV) and LHC ($\sqrt{s}=2.76$ TeV) energies. We find that at $p_T\sim 10$ GeV the pion spectrum is suppressed by $\sim 20{-}30\,(25{-}35)\%$ for RHIC (LHC), for $D$ ($B$) mesons the suppression effect is smaller by a factor of $\sim 0.7{-}0.8$ ($0.5$). The flavor hierarchy $R_{pp}^\pi<R_{pp}^D<R_{pp}^B$ is held at $p_T\lesssim 20$ GeV for RHIC and at $p_T\lesssim 70$ GeV for LHC. This gives a sizeable reduction of the heavy-to-light ratios of the nuclear modification factors $R_{AA}$ as compared to that in the standard scenario without the QGP production in $pp$ collisions.