Laboratory Astrophysics

The physics of plasmas plays a vital function in many astrophysical phenomena and the incorporation of these fundamental concepts in the interpretation of observations cannot be underestimated, and in many cases is essential for a proper explanation. Many astro-plasma physics systems are complex and nonlinear. The multi-scale nature of much of this physics remains beyond numerical simulation, so a direct experimental approach is particularly helpful. Furthermore, astrophysics relies on remote sensing, whereas experiment allows repeated in situ probing and the freedom to alter input conditions.  Experiments are thus a critical tool in the validation of sophisticated multi-dimensional computer models.

Examples of astro-plasma systems suitable for laser-plasmas experiments include supernovae,
supernova remnants, protostellar jets, and jets associated with accreting compact objects.

Planetary Nebulae

The subject has already advanced the understanding of hydrodynamic instabilities in the astrophysics context and has driven the development of more sophisticated computational models and diagnostic techniques.

The HiPER proposal offers the potential to extend the sophistication of experiments to higher density and temperature, with longer spatial and temporal scales, driving a step change advance in laboratory astrophysics. The combination of energetic long and short duration laser beams is novel and enables the creation of plasmas to simulate the ejection of winds and jets from highly evolved stars into interstellar medium, the formation of collisionless shocks and other high energy density systems. Future proposed experiments include studies of cosmic ray seeding and acceleration, and gamma ray bursters. HiPER will enable the study of colliding plasma systems, hydrodynamic instabilities and turbulence, photon-dominated plasmas and relativistic plasmas.

Furthermore, the possibility to generate enormous magnetic fields (in excess of a GigaGauss) over long length scales can lead to conditions otherwise only found on the surfaces of white dwarf and neutron stars. This allows the study of atomic systems in which the magnetic rather than the electric field dominates, and where motion of charged particles and characteristics of collective plasma processes are influenced by the ultra intense magnetic fields.