Characteristics of laser produced plasmas of hafnium and tantalum in the 1–7 nm regionBowen Li, Takamitsu Otsuka, Emma Sokell, Padraig Dunne, Gerry O’Sullivan, Hiroyuki Hara, Goki Arai, Toshiki Tamura, Yuichi Ono, Thanh-Hung Dinh and Takeshi HigashiguchiEur. Phys. J. D, 71 11 (2017) 278DOI: https://doi.org/10.1140/epjd/e2017-70830-6