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In H 2 discharges of large helical device (LHD), H-mode-like transition has been obtained with edge localized mode (ELM)-like bursts in an outwardly shifted configuration of R ax= 4.00 m with an extremely thick ergodic layer, where the ι/2π= 1 position is located in the middle of the ergodic layer. This H-mode-like transition can be triggered by changing P NBI (< 12 MW) from 3 beams to 2 beams in a density range (4–8)× 10 13 cm− 3. The spontaneous H-mode-like transition is also observed during a stable discharge with constant heating power and density, where a steep edge pressure gradient is formed at the ι/2π= 1 position. The ELM-like bursts occurred in the ergodic layer accompanied with density bursts. It is found that the density bursts triggered at the ι/2π= 1 position in the ergodic layer instantaneously propagate outward beyond the ergodic layer with positive density pulse, and a few ms later also begin to …