The MIT Vault Laboratory

CSTAR is unique amongst many university facilities in that it is home to a high bay 18' x 30' (5.5m x 9.1m) underground vault with 3' (0.9m) thick high density concrete shielding walls that allow high fluence radiation experiments to be safely performed. Two additional shielded rooms - one 14' x 36' (4.3m x 11m') and 8' x 30' (2.4m x 9.1m) - provide space for accelerators and beamline ports into the vault. All rooms are fully interlocked during operation for personnel safety. The vault contains the target chambers for the DANTE accelerator - allowing DANTE to produce high-current deuteron beams - the DT neutron generator, and several large neutron and gamma sources. Shielded multiturn ducts provide access for external power, signal, and internet network cabling. All systems, including in-vault digital data acquistion systems, are operated remotely from the control room.

DANTE is a 1.5 MV tandem electrostatic accelerator, manufactored by Newton Scientific Industries in Cambridge, MA. Originally designed to produce high neutron yields for use in cancer therapy research, the accelerator's multicusp ion source and extraction optics allow for DC beam currents of up to several hundred micro-Amperes at the high-energy end of the accelerator. DANTE typically runs proton or deuteron beams for the production of fast neutrons and gamma rays, but the source can also be configured to produce heavy ion beams. DANTE's beamline runs through a port into the shielded vault, allowing for high-radiation production experiments to be performed. Inside the vault, a selection magnet can be used to steer the beam to one of four experimental target stations off of the main diagnostic beamline.

The Vault's DT neutron generator - model A320 produced by Thermo Fisher Inc. - is a compact, highly efficient source of isotropic, 14.1 MeV neutrons. Using a small, internal 100 kilovolt maximum electrostic accelerator, the DT generator is capable of producing approximately 3x10⁸ neutrons per second via the ³H(d,n)³He nuclear reaction, better known as the D-T fusion reaction. The DT generator is used in a variety of experiments, including radiation detector development and characterization, fast neutron imaging, and material activation.