Laboratory for Experimental Nuclear Astrophysics (LENA)

The LENA is among only a few accelerator facilities in the world dedicated entirely to nuclear astrophysics experiments. It has two low-energy electrostatic accelerators that are capable of delivering high-current charged-particle beams to a common target. One is an ECR source on a 200-kV platform and the other one is a 1-MV JN Van de Graaff accelerator. Both accelerators are fully computer-controlled and transport ion beams to a common target. LENA is unique in the sense that it will cover the whole energy range below 1~MeV with ion beams of high intensity and stability.



The LENA facility is used for directly measuring astrophysically important cross sections and resonance strengths at low bombarding energies. LENA consists of two major components, a 1 MV JN accelerator and a 200 kV accelerator. Both accelerators deliver protons or alpha-particles into the same beamline. The smaller machine provides currents of up to 1 mA on target (this is a crucial requirement for measuring very weak cross sections at low bombarding energies), while the larger accelerator is used for periodically checking the target stability (for example, by measuring well-known resonances located at higher energies).