  Conditions similar to those at the end of the divertor leg in a tokamak were
replicated in the linear plasma machine Magnum-PSI. The neutral pressure in the
target chamber is then increased to cause the target to transition from an
attached to a detached state. Superimposed to this steady state regime,
ELM-like pulses are reproduced, resulting in a sudden increase in plasma
temperature and density, such that the heat flux increases transiently by half
an order of magnitude. Visible light emission, target thermography, and Thomson
scattering are used to demonstrate that the higher the neutral pressure the
more energy is removed from the ELM-like pulse in the volume. If the neutral
pressure is sufficiently high, the ELM-like pulse can be prevented from
affecting the target and the plasma energy is fully dissipated in the volume
instead (ID 4 in Table 1). The visible light images allow the division of the
ELM-plasma interaction process of ELM energy dissipation into 3 "stages"
ranging from no dissipation to full dissipation (the target plasma is
detached). In the second publication related to this study, spectroscopic data
is analysed with a Bayesian approach, to acquire insights into the significance
of molecular processes in dissipating the plasma energy and particles.
