Spallation device for producing neutrons

Spallation device for production of neutrons, comprising:

• a spallation target configured to produce neutrons by interaction with a particle beam;
• a source of a liquid spallation material for the spallation target;
• a first chamber containing the spallation target and including an annular flow region having an inlet to receive the liquid spallation material;
• a second chamber in which the particle beam will propagate towards the spallation target, along a propagation axis;
• a hollow particle beam generator that generates a hollow particle beam that surrounds the propagation axis;
• a leak tight partition through which the particle beam can pass, separating the first chamber from the second chamber and reaching the propagation axis;
• and
• the first chamber having ribs spaced around a side wall of the first chamber downstream from said inlet and adjacent a part of the leak tight partition through which the particle beam passes, said ribs terminating a distance into the first chamber.