37 research outputs found
Search for anisotropic effects of hcp solid helium on optical lines of cesium impurities
The anisotropic effect of a hcp 4He solid matrix on cesium atoms has been
proposed as a tool to reveal the parity violating anapole moment of its
nucleus. It should also result in splitting the D2 optical excitation line in a
way depending on the light polarization. An experimental investigation has been
set up using oriented hcp helium crystals in which cesium metal grains are
embedded. Atoms are created by laser sputtering from this grains. Optical
absorption spectra of the D2 line have been recorded in the temperature range
of 1.0 to 1.4 K at liquid/solid coexistence pressure by monitoring the
fluorescence on the D2 line at 950 nm. No significant effect of the light
polarization has been found, suggesting a statistically isotropic disordered
solid environment for the cesium atoms.Comment: The original publication will be available at
http://www.springerlink.co
Properties of superfluid fog
A dense fog consisting of superfluid \chem{{}^4 He} droplets can
be generated in helium vapor up to a height of 4–6\un{cm} from
the helium surface by driving a piezo transducer plate immersed
under the liquid. The average droplet size ranges from about
100\un{\mu m} at a drive frequency of 1\un{kHz} to 10\un{\mu m} at
100\un{kHz}, and the frequency dependence is consistent with the
capillary-wave dispersion relation of the helium surface, with the
droplets ejected from the surface being about one wavelength in
diameter. It appears that the helium vapor is set into motion
along with the droplets, greatly reducing the viscous drag on the
droplets and making possible the substantial fog heights above the
surface
Criteres d'utilisation de microalgues pour le nourrissage de crassostrea gigas et d'ostrea edulis en ecloserie
SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : 22543, issue : a.1996 n.51 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
Angular Effects in Proton-Induced Single-Event Upsets in Silicon-on-Sapphire and Silicon-on-Insulator Devices
We present new data in the ongoing effort to bound the effect of proton angle of incidence on the single-event upset (SEU) rate in silicon-on-sapphire (SOS) and silicon-on-insulator (SOI) devices