SPARC: Interaction with High-Intensity Lasers

Ultra High Field Physics in Combination of Relativistic Heavy Ions and Lasers

With the extremely short, relativistic enhanced field pulses produced by ions at relativistic energies, the critical field limit (Schwinger limit) for lepton pair production can be surpassed by orders of magnitudes in heavy ion collision. The detection methods of reaction microscopes will give the momentum of all fragments when atoms or molecules are disintegrating in strong field pulses of the ions down to low energies where the atomic interactions are dominated by strong perturbations and quasi- molecular effects.
The other class of experiments will focus on structure studies of selected highly-charged ion species, a field that is still largely unexplored; with determinations of properties of stable and unstable nuclei by atomic physics techniques on the one hand, and precision tests of quantum electrodynamics (QED) and fundamental interactions in extremely strong electromagnetic fields on the other hand.
Different complementary approaches will be used such as relativistic Doppler boosts of optical or X-UV laser photons [1] to the X-ray regime, or coherent radiation by channeling of relativistic ions, or electron-ion recombination, or electron and photon spectroscopy that will give hitherto unreachable accuracies.

Advanced Light Sources

In the last few years, technological bottlenecks in high-energy laser technology have been overcome. First, news schemes to operate large glass laser systems at moderate to high shot rates are now emerging and second, these lasers are becoming more and more reliable, so that further non-linear amplifications schemes and secondary sources can be envisioned. This culminated with the introduction by G. Mourou et al. of the C3 scheme [2], allowing one to think about experimental science at the levels well above 10-PW.
GSI has an extensive experience in building and operating such high energy lasers like the PHELIX [3] facility. This laser is successfully supporting the experimental program of the Helmholtz association and in particular in the field of atomic physics. Because of the existing strong local expertise and the opportunities offered in combined laser-ion experiments, PHELIX can be easily upgraded and it is the ideal testbed to prepare the next generation of high-energy lasers.
With modern laser systems, secondary laser-driven sources are a central theme of the facility. Secondary sources from laser-accelerated ions [4] to coherent and non-coherent X-rays are currently actively being developed with strong application potential for FAIR. All these themes form a new and lively field at the crossroad of laser and accelerator research [5].