Compact electron beam ion trap for spectroscopy of moderate charge state ions

A compact electron beam ion trap (EBIT) has been constructed for spectroscopic studies of moderate charge state ions. The electron beam energy range of the present EBIT is 100-1000 eV, for which it is rather difficult to operate an ordinary EBIT which used to be designed for operation with higher electron energy (~10 keV or more). To cut down the running costs, a superconducting wire with a high critical temperature is used for the central magnet so that it can be operated without liquid helium. The performance of the compact EBIT has been investigated through visible spectroscopy of highly charged krypton and iron ions.