Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSolution of the Boltzmann equation for gluons after a heavy ion collision
99
0
0.0
(
0
)
Authors
Jefferson Bjoraker
Ask ChatGPT about the research
No Arabic abstract
A non-linear Boltzmann equation describing the time evolution of a partonic system in the central rapidity region after a heavy ion collision is solved numerically. A particular model of the collinear logarithmic divergences due to small angle scattering is employed in the numerical solution. The system is followed until it reaches kinetic equilibrium where the equilibration time, temperature and chemical potential are determined for both RHIC and LHC.
rate research
Read More
The final stage of a relativistic heavy-ion collision is a hadron gas. Final-state interactions therein distort the $p_T$ spectrum of particles coming from the phase transition upon cooling the quark-gluon plasma. Using recent state-of-the-art parametrizations of pion interactions we provide theoretical computations of the pionic depth of the gas: how likely is it that a given pion rescatters in it (we find a high probability around $p_T=0.5$ GeV at midrapidity, corresponding to the formation of the $rho$ resonance), a comparison of the collision and Bjorken expansion rates, and how many pions make it through without interacting as a function of $p_T$. This is in the range 10-24$%$ and shown in this plot, the main result of the contribution.
We have developed a numerical framework for a full solution of the relativistic Boltzmann equations for the quark-gluon matter using the multiple Graphics Processing Units (GPUs) on distributed clusters. Including all the $2 to 2$ scattering processes of 3-flavor quarks and gluons, we compute the time evolution of distribution functions in both coordinate and momentum spaces for the cases of pure gluons, quarks and the mixture of quarks and gluons. By introducing a symmetrical sampling method on GPUs which ensures the particle number conservation, our framework is able to perform the space-time evolution of quark-gluon system towards thermal equilibrium with high performance. We also observe that the gluons naturally accumulate in the soft region at the early time, which may indicate the gluon condensation.
The estimate based on the parton model is made on the rate of production of Super Heavy Particle ( SHP ) in subthreshold collision of heavy ions at LHC. For the one month run of lead-lead collision the yield of 16 TeV particle is of the order of 70 per year.
We present an exact solution to the Boltzmann equation which describes a system undergoing boost-invariant longitudinal and azimuthally symmetric radial expansion for arbitrary shear viscosity to entropy density ratio. This new solution is constructed by considering the conformal map between Minkowski space and the direct product of three dimensional de Sitter space with a line. The resulting solution respects SO(3)_q x SO(1,1) x Z_2 symmetry. We compare the exact kinetic solution with exact solutions of the corresponding macroscopic equations that were obtained from the kinetic theory in ideal and second-order viscous hydrodynamic approximations. The macroscopic solutions are obtained in de Sitter space and are subject to the same symmetries used to obtain the exact kinetic solution.
The pseudorapidity distribution of charged hadron over a wide $eta$ range gives us crucial information about the dynamics of particle production. Constraint on the detector acceptance, particularly at forward rapidities, demands a proper distribution function to extrapolate the pseudorapidity distribution to large $eta$. In this work, we have proposed a phenomenological model based on Pearson statistical framework to study the pseudorapidity distribution. We have analyzed and fit data of charged hadrons produced in $Pb-Pb$ collision at $2.76$ TeV and $Xe-Xe$ collision at $5.44$ TeV using the proposed model.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
