The CERN Large Hadron Collider as a Tool to Study High-Energy Density Matter

The Large Hadron Collider (LHC) at CERN will generate two extremely powerful 7 TeV proton beams. Each beam will consist of 2808 bunches with an intensity per bunch of $1.15\times {10}^{11}$ protons so that the total number of protons in one beam will be about $3\times {10}^{14}$ and the total energy will be 362 MJ. Each bunch will have a duration of 0.5 ns and two successive bunches will be separated by 25 ns, while the power distribution in the radial direction will be Gaussian with a standard deviation, $\sigma =0.2\mathrm{mm}$. The total duration of the beam will be about $89\mu \mathrm{s}$. Using a 2D hydrodynamic code, we have carried out numerical simulations of the thermodynamic and hydrodynamic response of a solid copper target that is irradiated with one of the LHC beams. These calculations show that only the first few hundred proton bunches will deposit a high specific energy of $400\mathrm{kJ}/\mathrm{g}$ that will induce exotic states of high energy density in matter.

Figure 1

Specific energy deposited by one bunch along the target axis ($\mathrm{\text{time}}=1\mathrm{ns}$).

Figure 2

Specific energy vs transverse coordinate at different longitudinal positions ($\mathrm{\text{time}}=1\mathrm{ns}$).

Figure 3

Material state at $t=500\mathrm{ns}$.

Figure 4

Material state at $t=2.5\mu \mathrm{s}$.

Figure 5

Temperature vs transverse coordinate at different times at a longitudinal position of 16 cm.

Figure 6

Density vs transverse coordinate at different times at a longitudinal position of 16 cm.

Figure 7

Density and temperature at the target center vs time.

Figure 8

Plasma coupling parameter $\Gamma$ as a function of temperature and density.

Figure 9

Degree of ionization in the plasma as a function of temperature and density.