Federal funding has been approved for construction of the Bates Large Acceptance Spectrometer Toroid (BLAST) project at the Bates Linear Accelerator Center in Middleton.
BLAST, a detector designed specifically to work in conjunction with the new Bates South Hall Ring, will help an international collaboration of 40 scientists study the structure of protons, neutrons and light nuclei. The project, funded by the Department of Energy's Division of Nuclear Physics, will cost approximately $4.5 million and will take about four and a half years to complete.
Although scientists have known for more than 60 years that atomic nuclei are composed primarily of protons and neutrons, they do not yet understand the detailed structure of the protons and neutrons themselves. It is believed that each contains three quarks, the fundamental building blocks of most of the observed mass in the universe, but how the quarks and other constituents are arranged has proven to be an important question which is frustratingly hard to answer.
The Bates South Hall Ring will provide polarized (spinning) electrons which will strike polarized nuclear targets. Researchers expect that observations of how the relative directions of spinning affect the particles which are produced in the collisions will be especially sensitive to the detailed structure of the protons, neutrons and light nuclei.
The BLAST detector will consist of an eight-sector copper coil array producing a toroidal magnetic field, instrumented on two sides with particle identification and tracking modules. The design aims to use proven technology, commercial electronics and existing data acquisition system software to achieve low cost and a short construction time. The gaseous polarized nuclear targets will be internal to the South Hall Ring to provide very small backgrounds for these precise experiments.
Bates, a part of the MIT Laboratory for Nuclear Science, has served the nuclear physics community for over 25 years. More than 250 scientists from 11 different countries use the facility on a regular basis.
For more information on BLAST, visit the Web site at <http://mitbates.mit.edu/~blast/>.
A version of this article appeared in MIT Tech Talk on February 12, 1997.
