The MiniBooNE experiment continues to progress. It is now running about at about 30% of its design value. Operations are largely limited to the ability of the injector accelerator complex to produce beam (see below). Thus far, operations have been quite smooth with minimal radiological effects. At these intensities, it is not yet possible to measure airborne radionuclide emissions, and so far, the sophisticated horn-based focusing system is functioning reliably as designed. Exposures to personnel due to MiniBooNE operations remain low. Minor problems tangentially related to radiation safety are being identified and fixed as they arise. This correspondent has been told that the neutrino events being studied by the experiment are of exceptionally high quality, so the scientific potential of the experiment is promising.
Despite the prominence of MiniBooNE, the highest priority of the Fermilab physics research program is that of Tevatron Run II. Operations are being improved on an incremental basis, and these successes were recognized in a recent "independent" review. One can read more about this review in a recent article in Ferminews.
Regularly, new records in both initial luminosity of colliding beam "stores" and integrated luminosity over a given calendar week are set. However, Fermilab is becoming increasingly aware of the stresses being placed on the injector accelerator stages by both Run II and MiniBooNE. In particular, the 8-GeV booster synchrotron is now over 30 years old and is being asked to accelerate more protons in a single year than it has accelerated in its previous history. Because of this, inside the booster enclosure elevated radiation levels are now appearing where they have never existed before -- not even during the heady days of the massive 400-GeV fixed-target physics research program of the late 1970s. Efforts are underway to attempt to address these problems, perhaps with collimation installed at strategic locations in the accelerator lattice.
One would not normally think of the Fermilab accelerator as a scientific instrument for use in geology. Nonetheless, the major Alaska earthquake of November 3, 2002, resulted in beam losses in the Fermilab accelerators. This was particularly noticeable in the Tevatron, where the particle beam was lost due to a beam-loss-induced quench of the superconducting magnets. The beam losses were the direct result of vibrations of the beam line components set into motion by the seismic wave from the earthquake.
Particularly in Tevatron collider operations, great sensitivity to physical alignment is always present due to the nature of colliding beam accelerator physics. When the quench occurred and the beam disappeared, members of the Beams Division staff recognized a similarity in the loss pattern to that seen when a minor earthquake occurred in Indiana in June 2002. (Note, particularly for the West Coast audience: Yes, Indiana, along with outstanding basketball, regularly has mild earthquakes. These are usually connected with the famous New Madrid Fault in southeastern Missouri.) A check with geologists at nearby Northern Illinois University verified that the time of the beam loss matched the expected arrival time of the pressure wave from the earthquake that caused the beam-loss-inducing vibrations of the components.
A more detailed write-up can also be found in a recent article in Ferminews.
It is interesting to note that recognizing the earthquake to be the cause of the quench allowed the accelerator operators to resume operations much sooner than might have been the case had they decided to spend more time looking for other causes. This view of the "big picture" might have even spared some radiation exposures to people sent into the beam enclosure looking for a nonexistent "local" problem. The moral of this story is to "think outside of the box"!