Coherence-preserving trap architecture for long-term control of giant Ryberg atoms.

We present a way to trap a single Rydberg atom, make it long-lived, and preserve an internal coherence over time scales reaching into the minute range. We propose to trap using carefully designed electric fields, to inhibit the spontaneous emission in a nonresonant conducting structure, and to maintain the internal coherence through a tailoring of the atomic energies using an external microwave field. We thoroughly identify and account for many causes of imperfection in order to verify at each step the realism of our proposal.

Physical, performance, and dosimetric characteristics of the delta-Scan 50 whole-body/brain scanner.

The delta-Scan 50 computed tomographic (CT) scanner has the ability to determine x-ray attenuation coefficients with a precision ranging from 0.3 to 2.6% depending upon such factors as patient size and scan diameter. Resolution is 20-80% greater than the pixel width, with values ranging from 1.2 to 2.1 mm. The collimating system determines certain characteristics of the image and affects the dose to the patient: doses for typical procedures are on the order of 1 rad, and gonadal doses are in the millirad range. Potential improvements are discussed.