New data and inter-machine comparisons are presented exploring the role of rotation, ρ and error fields in governing tearing mode β limits. It is found that conventional aspect ratio tokamak βN limits due to 2/1 tearing modes fall from values in excess of 3 with the usual strong neutral beam torque injection, to ~2 in low torque plasmas for ITER-like baseline scenarios. The fractional rates of ...

In the standard scenario of tokamak plasma operation, sawtooth crashes are the main perturbations that can trigger performance-degrading, and potentially disruption-generating, neoclassical tearing modes. This Letter demonstrates sawtooth pacing by real-time control of the auxiliary power. It is shown that the sawtooth crash takes place in a reproducible manner shortly after the removal of that...

A 40-year-old woman presented with severe vaginal bleeding. Initial workup with an abdominal sonography revealed endometrium for about 3 mm and free fluid in the abdomen. Hemodynamic instability with abdominal pain and free fluid in the abdomen prompted blood transfusion and laparotomy. There were about 1000 cc blood and clots in the abdomen at laparotomy. There was a longitudinal rupture from ...

A simple theoretical model is developed which describes how current eddies are excited in the scrape-off layer SOL of a large-aspect-ratio, low, circular cross-section tokamak by time-varying magnetohydrodynamical instabilities originating from within the plasma. This model is used to study the interaction of SOL currents with tearing modes and resistive wall modes in a typical tokamak plasma. ...

The nonlinear dynamics of magnetic tearing islands imbedded in a pressure gradient driven turbulence is investigated numerically in a reduced magnetohydrodynamic model. The study reveals regimes where the linear and nonlinear phases of the tearing instability are controlled by the properties of the pressure gradient. In these regimes, the interplay between the pressure and the magnetic flux det...