High-Brightness Wavelength-Beam-Combined Eyesafe Diode Laser Stacks
At 1450 nm, we have demonstrated 20-W wavelength-beam-combined output from a 25- element single bar (M<sup>2</sup> ~ 1.9 times 10), and 80-W cw from a 6-bar diode stack (M<sup>2</sup> ~ 36 times 68).
Advances in high-brightness high-power semiconductor lasers
We present recent advances in high power semiconductor laser bars and arrays at wavelengths from the near infrared to the eye-safe regime including increased spectral brightness with internal gratings to narrow and stabilize the spectrum, increased spatial brightness with multimode and high power single mode performance, and reduced cost architectures from high power surface emitting 2-dimensional arrays. These devices have the potential to dramatically improve diode pumped systems and enable new direct diode applications.
5.63 and 5.80 MeV levels of Ne20; de-excitation branching
Abstract The ratio Г γ /Г for the 5.63 and 5.80 MeV levels of Ne 20 has been determined to be 0.077 (±0.008) and −4 , respectively, by using the C 12 (C 12 , α)Ne 20 reaction and determining the fraction of the events in which the alpha-particle and the Ne 20 recoil are present in coincidence at the kinematically correct angles. In both cases these results in themselves are shown to imply radiative E1 transition (5.63→1.63 and 5.80→0, respectively) probabilities ⪡5 × 10 −5 Weisskopf units. When taken together with the life-time for the 5.63 MeV level measured by Evans et al . values of Г( E1 ) ≲ 5 × 10 −6 and Г α ≈ 6% of the particle estimate are obtained for this state.