In situ melting phenomena on W plasma-facing components for lower divertor during long-pulse plasma operations in EAST oleh D. Zhu, Z. Guo, C. Xuan, B. Yu, C. Li, B. Gao, R. Ding, R. Yan, Y. Wang, C. He, D. Yao, L. Cao, P. Zi, L. Han, B. Wang, W. Fu, Y. Li, J. Chen, the EAST Team