QCD at high density: Equation of state for nuclear collisions and neutron stars

A unified chiral mean field approach is presented for QCD thermodynamics in a wide range of temperatures and densities. The model simultaneously gives a satisfactory description of lattice QCD thermodynamics and fulfills nuclear matter and astrophysical constraints. The resulting equation of state can be incorporated in relativistic fluid-dynamical simulations of heavy-ion collisions and neutron stars mergers. Access to different regions of the QCD phase diagram can be obtained in simulations of heavy-ion data and observations of neutron star mergers.Comment: 4 pages, 2 figures. Contribution to the Quark Matter 2018 conference proceeding

Identifying the nature of the QCD transition in heavy-ion collisions with deep learning

In this proceeding, we review our recent work using deep convolutional neural network (CNN) to identify the nature of the QCD transition in a hybrid modeling of heavy-ion collisions. Within this hybrid model, a viscous hydrodynamic model is coupled with a hadronic cascade “after-burner”. As a binary classification setup, we employ two different types of equations of state (EoS) of the hot medium in the hydrodynamic evolution. The resulting final-state pion spectra in the transverse momentum and azimuthal angle plane are fed to the neural network as the input data in order to distinguish different EoS. To probe the effects of the fluctuations in the event-by-event spectra, we explore different scenarios for the input data and make a comparison in a systematic way. We observe a clear hierarchy in the predictive power when the network is fed with the event-by-event, cascade-coarse-grained and event-fine-averaged spectra. The carefully-trained neural network can extract high-level features from pion spectra to identify the nature of the QCD transition in a realistic simulation scenario.publishedVersio

Laser induced proton acceleration by resonant nano-rod antenna for fusion

Recently laser induced fusion with simultaneous volume ignition, a spin-off from relativistic heavy ion collisions, was proposed, where implanted nano antennas regulated and amplified the light absorption in the fusion target. Studies of resilience of the nano antennas were published recently in vacuum and in UDMA-TEGDMA medium. These studies concluded that the lifetime of the plasmonic effect is longer in medium, however, less energy was observed in the UDMA-TEGDMA copolymer, due to the smaller resonant size of gold nanoantenna than in case of Vacuum. Here we show how the plasmonic effect behaves in an environment fully capable of ionization, surrounded by Hydrogen atoms close to liquid densities. We performed numerical simulations treating the electrons of gold in the conduction band as strongly coupled plasma. The results show that the protons close to the nanorod's surface follow the collectively moving electrons rather than the incoming electric field of the light. The results also show that the plasmonic accelerating effect is also dependent on the laser intensity.Comment: arXiv admin note: text overlap with arXiv:2212.0363