We review recent developments in the theoretical description of the initial state and collective dynamics in heavy ion and light-heavy ion collisions. After describing the current state of the art in event by event simulations of high energy nuclear collisions we will focus on open issues. These include early time non-equilibrium dynamics, small collision systems (p+p, p+A), hydrodynamic fluctu...

We calculate the spatial correlation of electrons and positrons emitted by internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The alignment or polarization of the nucleus results in an anisotropic emission of the electron-positron pairs which is closely related to the anisotropic emission of γ-rays. However, the angular correlation in the case of internal pair conversio...

The scattering cross sections of charm mesons with hadrons such as pion, rho meson and nucleon are studied in an effective Lagrangian. In heavy ion collisions, rescattering of produced charm mesons by hadrons affects both their transverse mass spectra and the invariant mass spectrum of dileptons resulting from their decays. These effects are estimated for heavy ion collisions at SPS energies an...

We calculate the spatial correlation of electrons and positrons emitted by internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The alignment or polarization of the nucleus results in an anisotropic emission of the electron-positron pairs which is closely related to the anisotropic emission of γ-rays. However, the angular correlation in the case of internal pair conversio...

The first Pb+Pb collisions at the Large Hadron Collider (LHC) at √ sNN = 5.52 TeV are imminent. Heavy ion collisions at the LHC provide an extended energy lever arm to the existing measurements made at RHIC and SPS, especially in hard (large-Q) processes. In this contribution an overview of the ATLAS detector is given and the current physics focus of Heavy Ion Working Group is discussed.

The synchrotron photon spectrum in heavy ion collisions is computed taking into account the spatial and temporal structure of the magnetic field. It is found that a significant fraction of photon excess in heavy ion collisions in the region k ⊥ = 1–3 GeV can be attributed to the synchrotron radiation. Azimuthal anisotropy of the synchrotron photon spectrum is characterized by the Fourier coeffi...

We employ stochastic modelling of statistical reactions with memory to study quasiperiodic oscillations in the excitation functions of dissipative heavy-ion collisions. The Fourier analysis of excitation function oscillations is presented. It suggests that S-matrix spin and parity decoherence, damping of the coherent nuclear rotation and quantum chaos are sufficient conditions to explain the no...

Strange particles such as the kaon and lambda are useful in probing the properties of dense matter formed in heavy ion collisions. We review in this talk the theoretical understandings of their properties in nuclear medium based on both the effective chiral Lagrangian and the phenomenological hadronic model. We further review the effects due to changes in their in-medium properties on their col...