Measurement of azimuthal anisotropy at high $p_\mathrm{T}$ using subevent cumulants in pPb collisions at CMS

The second-order (elliptic) Fourier coefficients ($v_{2}$) as a function of particle transverse momentum ($p_\mathrm{T}$) and event multiplicity are presented for pPb collisions using a subevent multiparticle cumulant analysis where nonflow effects are strongly suppressed. The data were recorded by the CMS experiment at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{_{\mathrm{NN}}}} = 8.16$ TeV. The new measurement probes an extended range of particle $p_\mathrm{T}$, up to values where the influence of nonflow effects are shown to strongly influence the results using a standard cumulant analysis. Results for both pPb and PbPb collisions are compared in similar multiplicity ranges, allowing for an assessment of the medium influence on the elliptic anisotropy associated with high $p_\mathrm{T}$ particle production.