Zobrazeno 1 - 10
of 88
pro vyhledávání: '"Bergeson, S. D."'
Publikováno v:
Phys. Lett. B 767, 171-176 (2017)
We report on measurements of relative beta-decay rates of Na-22, Cl-36, Co-60, Sr-90, Cs-137 monitored for more than one year. The radioactive samples are mounted in an automated sample changer that sequentially positions the five samples in turn, wi
Externí odkaz:
http://arxiv.org/abs/1612.00786
Autor:
Bergeson, S. D., Lyon, M.
We report measurements of the ion velocity distribution in an ultracold neutral plasma derived from a dense, cold Rydberg gas in a MOT. The Rydberg atoms are excited using a resonant two-step excitation pathway with lasers of 4 ns duration. The plasm
Externí odkaz:
http://arxiv.org/abs/1601.07439
We show that strong coupling between ions in an ultracold neutral plasma is limited by electron screening. While electron screening reduces the quasi-equilibrium ion temperature, it also reduces the ion-ion electrical potential energy. The net result
Externí odkaz:
http://arxiv.org/abs/1212.5113
We report new measurements and simulations of laser-induced fluorescence in ultracold neutral plasmas. We focus on the earliest times, when the plasma equilibrium is evolving and before the plasma expands. In the simulation, the ions interact via the
Externí odkaz:
http://arxiv.org/abs/0906.4724
We present measurements of the velocity distribution of calcium atoms in an atomic beam generated using a dual-stage laser back-ablation apparatus. Distributions are measured using a velocity selective Doppler time-of-flight technique. They are Boltz
Externí odkaz:
http://arxiv.org/abs/0810.5061
Autor:
Bergeson, S. D., Peatross, J. B., Eyring, N. J., Fralick, J. F., Stevenson, D. N., Ferguson, S. B.
We report on the development of a compact commercial instrument for measuring carotenoids in skin tissue. The instrument uses two light emitting diodes (LEDs) for dual-wavelength excitation and four photomultiplier tubes for multichannel detection. B
Externí odkaz:
http://arxiv.org/abs/0801.1697
Autor:
Bergeson, S. D., Robicheaux, F.
We present the first measurements and simulations of recombination fluorescence in ultracold neutral plasmas. In contrast with previous work, experiment and simulation are in significant disagreement. Comparison with a recombination model suggests th
Externí odkaz:
http://arxiv.org/abs/0708.2922
We demonstrate a novel compact solid-state laser source for high-resolution two-photon spectroscopy of the $1S-2S$ transition in atomic hydrogen. The source emits up to 20 mW at 243 nm and consists of a 972 nm diode laser, a tapered amplifier, and tw
Externí odkaz:
http://arxiv.org/abs/physics/0511162
We extend an isothermal thermal model of ultracold neutral plasma expansion to systems without spherical symmetry, and use this model to interpret new fluorescence measurements on these plasmas. By assuming a self-similar expansion, it is possible to
Externí odkaz:
http://arxiv.org/abs/physics/0508217
We report new detailed density profile measurements in expanding strongly-coupled neutral plasmas. Using laser-induced fluorescence techniques, we determine plasma densities in the range of 10^5 to 10^9/cm^3 with a time resolution limit as small as 7
Externí odkaz:
http://arxiv.org/abs/physics/0506069