ISOLDE RILIS: New beams, new facilities V.N. Fedosseev a, * , L.-E. Berg b , N. Lebas a , O.J. Launila b , M. Lindroos a , R. Losito a , B.A. Marsh a , F.K. O ¨ sterdahl b,z , T. Pauchard b , G. Transtro ¨mer b , J. Vannesjo ¨ b a CERN, CH-1211 Gene `ve 23, Switzerland b KTH-Royal Institute of Technology, SE-10044 Stockholm, Sweden Available online 5 June 2008 Abstract The resonance ionization laser ion source (RILIS) at the ISOLDE on-line isotope separator is based on the selective excitation of atomic transitions by tunable laser radiation. New ion beams have been produced with RILIS in recent years: Sb, Sc, Dy, Au, Hg and Po. In total, isotopes of 26 different elements have been selectively laser-ionized and separated at ISOLDE. In order to facilitate the work on development of atomic ionization schemes an off-line laser laboratory has been established at CERN. Operating indepen- dently of the on-line RILIS setup, this laboratory will be capable of providing extensive data on atomic transitions, in particular between highly excited and auto-ionizing atomic states, which are required for the improvement of the RILIS efficiency. Additionally, the pro- gram of upgrading the on-line RILIS system by the implementation of solid state lasers will be presented. Ó 2008 Elsevier B.V. All rights reserved. PACS: 29.25.Ni; 32.10.Fn; 32.80.Fb; 42.60.By; 42.62.Fi Keywords: Ion source; Laser photoionization; Laser spectroscopy 1. Introduction The intensity and physical composition of the ion beams produced at on-line ISOL facilities are strongly dependent on the type of source used to ionize the isotope of interest. Laser ion sources based on resonant excitation of atomic transitions by wavelength tunable lasers have been devel- oped and implemented at different ISOL facilities [1–5]. The main advantages of resonance ionization laser ion sources are the chemical selectivity of ionization and a con- venient way of manipulating the composition of the ion beams by turning on and off laser beams. An overview of the presently existing laser ion sources can be found in these proceedings [6]. At CERN, following the off-line development of the res- onance ionization laser ion source (RILIS) [2], the installa- tion of a permanent laser ion source at the PS-BOOSTER ISOLDE was proposed in 1993. The laser equipment was supplied from the Institute of Spectroscopy of the Russian Academy of Sciences (Troitsk, Moscow region) as a contri- bution to the ISOLDE programme. It included three cop- per vapor lasers operating in the Master Oscillator – Power Amplifier (MOPA) mode, three dye lasers and a set of optical and mechanical components for the laser beam control and focusing. The first physics run with the use of the RILIS was carried out in 1994 (experiment IS333: ‘‘Neutron-rich silver isotopes produced by a chemi- cally selective laser ion-source: test of the r-process ‘‘Wait- ing-Point” concept”). Since that time the output MOPA power has been increased from 40 W up to 80 W by the implementation of higher power laser tubes and a modern- ization of the laser power supplies. In addition, the wave- length tuning range was extended by using new dyes as well as by generating beams of the second and third har- monics. Presently, the annual usage of RILIS has exceeded 2000 h and for more than half of the available proton beam time, ISOLDE is running with RILIS. An overview of ion beams produced with RILIS will be given in next chapter. 0168-583X/$ - see front matter Ó 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.nimb.2008.05.038 * Corresponding author. E-mail address: Valentin.Fedosseev@cern.ch (V.N. Fedosseev). z Deceased. www.elsevier.com/locate/nimb Available online at www.sciencedirect.com Nuclear Instruments and Methods in Physics Research B 266 (2008) 4378–4382 NIM B Beam Interactions with Materials & Atoms