CMS Collaboration2019-01-112019-01-112018CMS Collaboration. "Elliptic Flow of Charm and Strange Hadrons in High-Multiplicity $p+\mathrm{Pb}$ Collisions at $\sqrt{{s}_{\mathrm{NN}}}=8.16\text{ }\text{ }\mathrm{TeV}$." <i>Physical Review Letters,</i> 121, no. 8 (2018) American Physical Society: https://doi.org/10.1103/PhysRevLett.121.082301.https://hdl.handle.net/1911/105091The elliptic azimuthal anisotropy coefficient (v2) is measured for charm (D0) and strange (K0S, Λ, Ξ−, and Ω−) hadrons, using a data sample of p+Pb collisions collected by the CMS experiment, at a nucleon-nucleon center-of-mass energy of √sNN=8.16 TeV. A significant positive v2 signal from long-range azimuthal correlations is observed for all particle species in high-multiplicity p+Pb collisions. The measurement represents the first observation of possible long-range collectivity for open heavy flavor hadrons in small systems. The results suggest that charm quarks have a smaller v2 than the lighter quarks, probably reflecting a weaker collective behavior. This effect is not seen in the larger PbPb collision system at √sNN=5.02 TeV, also presented.engPublished by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, andJournal articlehttps://doi.org/10.1103/PhysRevLett.121.082301