Ionization behavior of lawrencium (Lr, ) on surface ionization process

Sato, Tetsuya   ; Asai, Masato  ; Sato, Nozomi; Tsukada, Kazuaki  ; Toyoshima, Atsushi; Oe, Kazuhiro*; Miyashita, Sunao; Schdel, M.; Kaneya, Yusuke; Nagame, Yuichiro ; Osa, Akihiko  ; Ichikawa, Shinichi; Stora, T.*; Kratz, J. V.

In order to determine the first ionization potential of lawrencium (Lr, ), we have developed a surface ionization type ion-source coupled to a He/CdI gas-jet transport system for an Isotope Separator On-Line (ISOL) of the JAEA tandem accelerator experimental facility. We measured ionization efficiencies of short-lived Lr isotope and various short-lived lanthanide isotopes with our present system. We successfully ionized and mass-separated Lr ions for the first time and evaluated the first ionization potential of Lr based on a correlation between an effective ionization potential and ionization efficiencies of the lanthanide isotopes.