Experimental scaling of the scrape-off layer particle flux width by outboard divertor Langmuir probes with favorable Bt configuration on EAST

• DOI: 10.48550/arxiv.2206.08643
• Publication Date: 2022-01-01
• Authors: Xun Liu; Lingyi Meng; J.C. Xu; L Wang; Jie Li; the EAST Team
• Keywords: Langmuir Probe

The scrape-off layer (SOL) power width (\lambda_q) is important for predicting the heat load on divertor targets future magnetically confined devices. Currently, underlying physics \lambda_q scaling not fully understood. This paper extends previous inboard SOL particle flux (\lambda_{js}) [Liu et al 2019 Plasma Phys. Control. Fusion 61 045001] to outboard side in EAST, which can provide more experimental evidence study. A systematic method has been developed correct less reliable upper outer (UO) Langmuir probe (Div-LP) measurements with their neighboring reduce measurement uncertainty of \lambda_js. For discharges favorable Bt and single null configurations experiment campaign, about 260 have selected by certain criteria ensure good \lambda_js measurements. Three H-mode, L-mode, Ohmic databases constructed are used scalings. It found that H-mode L-mode plasmas scales as, \lambda_(js,UO)=1.52(W_{MHD}/n_e)^(-0.61) P_{tot}^0.19, where W_{MHD} stored energy, n_e line-averaged density, P_{tot} total input power. similar except amplitude probably due triangularity. repeatable dependence W_{MHD}/n_e confirms reliability this even though regression quality relatively poor. also discussed solely \lambda_q/\lambda_{js} Bp enough include all transports.