Future carbon beams at SPIRAL1 facility: which method is the most efficient?

Area of Science:

• Nuclear Physics
• Atomic Physics
• Accelerator Science

Background:

• Isotope Separator On-Line (ISOL) facilities offer high radioactive ion beam intensities but struggle with short-lived, reactive, and refractory elements.
• Producing radioactive carbon beams is challenging due to carbon's refractory nature, requiring advanced ionization techniques.
• Existing efforts focus on extending ISOL capabilities for difficult-to-produce ion beams, including carbon.

Purpose of the Study:

• To investigate the production of radioactive carbon ion beams using molecular precursors (CO, CO2) at ISOL facilities.
• To evaluate the performance of charge breeders and Electron Cyclotron Resonance (ECR) ion sources for carbon beam ionization.
• To compare charge breeding efficiencies and times for carbon ions using different ionization devices.

Main Methods:

• Experiments were conducted at LPSC using the Phoenix charge breeder and at GANIL with the Nanogan ECR ion source.
• Radioactive carbon beams were produced from molecular ions (CO, CO2), which were subsequently broken up and multi-ionized.
• Charge breeding efficiencies and ionization times were measured and compared between the Phoenix charge breeder and Nanogan ECRIS.

Main Results:

• Successful ionization of carbon beams using both the Phoenix charge breeder and Nanogan ECR ion source.
• Carbon was demonstrated as the lightest condensable element successfully charge bred with an ECR ion source.
• Charge breeding efficiencies and times were quantified, providing valuable data for future ISOL facility developments.

Conclusions:

• The study successfully demonstrates a viable method for producing radioactive carbon ion beams from molecular ions.
• The Phoenix charge breeder and Nanogan ECRIS show promise for ionizing challenging refractory elements like carbon.
• These findings contribute to extending the capabilities of ISOL facilities for producing a wider range of radioactive ion beams.