Project GRAND is large-field cosmic ray detector located in northern Indiana, on the campus of the University of Notre Dame. It is made up of an array of 64 proportional wire chamber stations. Each station is composed of four sets of two orthogonal planes with each plane containing 80 detection cells of 14mm width. The sets of planes are positioned above each other with 200 mm of separation between each pair of planes. This geometrical arrangement allows for the measurement of the direction of a muon track to within 0.26 degrees, on average, in each of the two projected planes. There is also a 50 mm steel plate above the bottom two planes. This steel plate and the two additional planes of proportional wire detector planes underneath enable tracks of secondary muons to be distinguished from electron tracks. A data rate of ~2000 muons per second is currently being recorded with the GRAND array.
Information from each detector station is sent serially to a central computer at a rate of 10 MHz. The data from the 64 stations are read in parallel into a central data acquisition system (DAS) in 70 microseconds. A single-node Linux-based VME-bus computer (Motorola MVME5100-0163) searches the hits from 512 proportional wire planes and remembers the wire numbers from the eight planes in any station that had one and only one hit on each plane of that station. The data buffer is written to a USB-interfaced IDE hard drive once every hour. The start time and end time of each record is recorded along with the wire numbers defining the angles for each of the recorded muons.
Project GRAND is operated by the Department of Physics (Astrophysics Group) at the University of Notre Dame under the direction of Professor Emeritus of Physics John Poirier, Ph.D. Project GRAND serves as active research site for undergraduate students at Notre Dame as well as those participating in the Research Experience for Undergraduate Students (REU) program. Participants from the Research Experience for Teachers (RET) and Research Experience for High School Students (REHS) also work at Project GRAND.