1. The scrape-off layer (SOL) refers to the region outside the last closed flux surface (LCFS) in a limiter plasma or outside the separatrix in a divertor plasma. The SOL is characterized by open field lines ending on material surfaces. The SOL governs the heat load on the plasma facing components, determines the power and particle balance and regulates the impurity dynamics. Therefore, understanding the SOL is essential for future reactor design. Transport in the SOL is determined to a huge fraction by intermittently occurring structures of enhanced plasma pressure. In the poloidal crosssection or drift-plane they appear compact and localized and therefore are called plasma blobs. These structures are also field-aligned and therefore also called plasma filaments. Blobs are driven by the interchange instability.  The propagation of the filaments follows rather simply scaling laws. The transport of filaments is intrinsically nonlocal and convective. However, it is possible to descibe the convective transport by an effective diffusivity.  

relevant publications with members of the working group

G. Birkenmeier, P. Manz et al 'Filament transport, warm ions and erosion in ASDEX Upgrade L-modes'  Nucl. Fusion 55 033018 (2015)

D. Carralero, P. Manz  et al. 'Experimental Validation of a Filament Transport Model in Turbulent Magnetized Plasmas' Phys. Rev. Lett. 115, 215002 (2015)

P. Manz et al. 'Filament velocity scaling laws for warm ions' Physics of Plasmas 20, 102307 (2013)

G. Fuchert et al. Blob properties in L- and H-mode from gas-puff imaging in ASDEX upgrade Plasma Phys. Control. Fusion 56 125001 (2014)

D. Carralero et al. 'Recent progress towards a quantitative description of filamentary SOL transport' Nucl. Fusion 57 056044 (2017)

D. Carralero et al 'On the role of filaments in perpendicular heat transport at the scrape-off layer'Nucl. Fusion 58 096015 (2018)