The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its
aspect ratio (A= R 0/a) reduced to A∼ 1.5, well below the normal tokamak operating range …

A fusion nuclear science facility (FNSF) could play an important role in the development of
fusion energy by providing the nuclear environment needed to develop fusion materials and …

The spherical tokamak (ST) is a leading candidate for a Fusion Nuclear Science Facility
(FNSF) due to its compact size and modular configuration. The National Spherical Torus …

The fast-ion D α (FIDA) diagnostic is an application of charge-exchange recombination
spectroscopy. Fast ions that neutralize in an injected neutral beam emit Balmer-α light with a …

Abstract The National Spherical Torus Experiment (NSTX) is currently being upgraded to
operate at twice the toroidal field and plasma current (up to 1 T and 2 MA), with a second …

A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost
to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather …

Full wave simulations of fusion plasmas show a direct correlation between the location of the
fast-wave cut-off, radiofrequency (RF) field amplitude in the scrape-off layer (SOL) and the …

This paper explores a range of high-performance equilibrium scenarios achievable with
neutral beam heating in the NSTX-Upgrade device (Menard JE 2012 Nucl. Fusion 52 …

Abstract Research on the National Spherical Torus Experiment, NSTX, targets physics
understanding needed for extrapolation to a steady-state ST Fusion Nuclear Science …

Fast-wave heating and current drive efficiencies can be reduced by a number of processes
in the vicinity of the antenna and in the scrape-off layer (SOL). On NSTX from around 25% to …