The UW Particle Astrophysics laboratory is engaged in two
separate projects, each of which is widely recognized as a world
leader in its field. Both projects have been the subjects of
intense public interest over the past several years.
wilkes@phys.washington.edu, young@phys.washington.edu
The UW Particle Astrophysics laboratory is engaged in two
separate projects, each of which is widely recognized as a world
leader in its field. Both projects have been the subjects of
intense public interest over the past several years.
Super-Kamiokande is a joint Japan-US collaboration operating the world's largest underground neutrino observatory. Neutrinos are subatomic particles which have no electrical charge, are very nearly massless, and interact only via the weak nuclear force. They are products of radioactive decay processes, and so are produced abundantly in our Sun, and in other astrophysical sources like supernovae and Active Galactic Nuclei (AGNs). Super-Kamiokande is located in the Kamioka Mine, about 200 km north of Tokyo, and is a water cerenkov detector, which means it is a large (40 meters diameter by 40 meters tall) tank of ultra-pure water viewed by thousands of sensitive phototubes. Super-K is supported by DOE.
JACEE (Japanese-American Cosmic Ray Emulsion chamber Experiment) is another US-Japan collaboration, which over the past 18 years has conducted long-duration balloon flights, including several record-breaking flights in Antarctica, to observe the flux of primary cosmic ray particles at the top of the earth’s atmosphere at the highest possible energies. The emulsion chamber detectors used in JACEE employ nuclear emulsion, etchable plastics, x-ray films, and other track sensitive materials for visualization of particle interactions. JACEE is supported by NSF.
Super-Kamiokande will address some of
the most important open questions in physics today, such as: why
does the Sun appear to produce only half as many neutrinos as
theory would predict? Do neutrinos have mass? Do protons decay,
as predicted by Grand Unification Theory?
JACEE provides the world standard cosmic ray spectrum at energies above 1014 eV, and addresses basic issues relating to the origin, acceleration and propagation of cosmic ray particles in our Galaxy.
Detailed and accurate simulation of the detector is crucial for almost all aspects of Super-Kamiokande data analysis. Monte Carlo simulations of neutrino interactions and detector response have been developed and run on Unix workstations, but the throughput is limited since these computers are primarily used for other tasks. We plan to adapt existing software to the Intel/NT platform and then refine and develop the simulations for more accurate simulation of detector response. We will then construct an integrated multi-processor "farm" for extensive, high-statistics running of this computationally intensive application.
JACEE data analysis requires extensive analysis of large
amounts of image data. We are developing a system for automated
analysis of track sensitive components of our detector. At
present several image analysis steps are seriously limited by
computing power available. We will employ Intel/NT platforms to
improve throughput and develop more straightforward visual
analysis displays and algorithms.
Two computer systems have been received and installed. A member of our group, Eric Zager, attended system management workshops provided, and serves as administrator for our intel machines. They are presently being used as software development workstations. Once additional units are received we can begin fulfilling the goals of our proposal.