CASPAR (Compact Accelerator System for Performing Astrophysical Research)
At the intersection of observational astronomy, astrophysics and nuclear physics, there stands the field of experimental low-energy nuclear astrophysics. Through the understanding of stellar burning processes, their energetics and mechanisms, we strive to build a picture of the chemical evolution of our Universe. The use of low-energy accelerator systems in the evaluation of stellar burning processes is a well-established technique, with many years of successful discoveries. The driving force is to push these measurements down into the stellar burning regime of astrophysical interest at lower energies. The natural tendency of these cross-sections (probability of reaction) at low energies is to drop off exponentially, making the detection of such events an extremely rare occurrence. The ever present abundance of cosmic-ray induced background inhibits such measurements by traditional means, swamping out the rarer events of interest sometimes by orders of magnitude.
CASPAR is an experimental system centered on the use of a 1 MV electrostatic accelerator system, located 4850 ft below the surface, at the Sanford Underground Research Facility (SURF) in Lead, South Dakota. A full laboratory and accelerator system is under construction underground as a collaboration between the University of Notre Dame, South Dakota School of Mines and Technology and Colorado School of Mines. First beam is anticipated in early 2016 for commissioning and calibration. The goal is to measure reactions of interest in the stellar burning regime utilizing the 4900 m.w.e shielding provided by the deep underground environment. Initial reactions of interest focus on, but are not restricted to, the production of seed neutrons for the s-process, specifically 13C(α,n) and 22Ne(α,n).