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The elliptic, triangular, quadrangular and pentagonal anisotropic flow coefficients for π ± , K ± and p+p in Pb-Pb collisions at √ s NN = 2.76 TeV were measured with the ALICE detector at the Large Hadron Collider. The results were obtained with the Scalar Product method, correlating the identified hadrons with reference particles from a different pseudorapidity region. Effects not related to the common event symmetry planes (non-flow) were estimated using correlations in pp collisions and were subtracted from the measurement. The obtained flow coefficients exhibit a clear mass ordering for transverse momentum (p T ) values below ≈ 3 GeV/c. In the intermediate p T region (3 < p T < 6 GeV/c), particles group at an approximate level according to the number of constituent quarks, suggesting that coalescence might be the relevant particle production mechanism in this region. The results for p T < 3 GeV/c are described fairly well by a hydrodynamical model (iEBE-VISHNU) that uses initial conditions generated by A Multi-Phase Transport model (AMPT) and describes the expansion of the fireball using a value of 0.08 for the ratio of shear viscosity to entropy density (η/s), coupled to a hadronic cascade model (UrQMD). Finally, expectations from AMPT alone fail to quantitatively describe the measurements for all harmonics throughout the measured transverse momentum region. However, the comparison to the AMPT model highlights the importance of the late hadronic rescattering stage to the development of the observed mass ordering at low values of p T and of coalescence as a particle production mechanism for the particle type grouping at intermediate values of p T for all harmonics.

Matrix representations of Maxwell's equations are very well-known. This is evident from the numerous studies on the close resemblance between the Maxwell equations in spinor form to the Dirac equation. However, all these matrix representations lack an exactness, as they assume the media to be homogeneous or/and time-independent. Moreover the final representation is given in terms of a pair of matrix equations. We present a matrix representation of Maxwell's equations in an inhomogeneous linear medium, in presence of sources. It is shown that such a representation necessarily requires 8 × 8 matrices and an explicit representation for them is presented.