C-AD Accelerator Physics Seminar

A number of data runs have been performed at TJNAF by the ALE Collaboration (with membership from TJNAF and SLAC). These runs were to study anomalous light emissions generated in the interior of high vacuum superconducting cavities (at 2 K) under (1.5 GHz) RF excitation. These light emissions and their associated phenomena were observed by a small monochrome video camera, looking through a standard optical viewport, as well as by other instrumentation. Of the several phenomena observed, the most perplexing are what appear to be small luminous long-lived objects moving about in the vacuum space in the interior of the cavities without wall contact (although at times these objects also bounced off of the cavity walls). In our several runs, more than a dozen (closed) orbits of these Mobile Luminous Objects (or MLOs) were observed, six of which lasted longer than 10 s. The orbit of longest duration lasted 40 s. These orbits were often elliptical or near elliptical. Orbital frequencies ranged from 5 to 80 Hz. This orbital motion is included in what we label as Mode I behavior, also described as ballistic behavior. By using reflections in the wall of the cavity beam tube (where available), it is shown that the trajectories of these orbits are in, or near, the equatorial plane of the cavity and not in contact with the cavity walls. A video clip of Mode I behavior is shown.
A second and even more intriguing MLO behavior, which we call Mode II, or macromolecular behavior, has also been observed. In this case, several MLOs gather into what might be a macromolecule, which appears to move as a single unit, the several MLOs appearing to be bonded to each other. (A configuration containing as many as seven MLOs was observed.) These configurations were seen not only to orbit (i. e., rotate about) the cavity axis in the cavity vacuum volume, but also to come to rest in the vacuum and not in contact with the cavity walls. A video clip of Mode II behavior is also shown.