165,217 research outputs found
Solar neutrinos as background in dark matter searches involving electron detection
In the present work we estimate the potential background of solar neutrinos
on electron detectors. These detectors are considered relevant for detecting
light dark matter particles in the MeV region, currently sought by experiments.
We find that the copious low energy pp neutrinos are a dangerous background at
the energies involved in these experiments, in fact close to the anticipated
event rate, while the more energetic Boron neutrinos are harmlessComment: 12 pages, 5 figures, Journal of Physics G: Nuclear and Particle
Physics, Volume 43, Number 7,Published 19 May 2016. arXiv admin note: text
overlap with arXiv:1605.0541
The total nucleon-nucleon cross section at large N_c
It is shown that at sufficiently large for incident momenta which are
much larger than the QCD, the total nucleon-nucleon cross section is
independent of incident momentum and given by . This result is valid in the extreme large
regime of and has corrections of relative order . A possible connection of this result to the
Froissart-Martin bound is discussed.Comment: 4 page
Multi-cell battery protection system
A multi-cell battery protection system is described wherein each cell has its own individual protective circuit. The protective circuits consist of a solid state comparator unit and a high current switching device such as a relay. The comparator units each continuously monitor the associated cell and when the cell voltage either exceeds a predetermined high level or falls below a predetermined low level, the relay is actuated whereby a bypass circuit is completed across the cell thereby effectively removing the cell from the series of cells
Cryogenic shutter
A magnetically operated shutter mechanism is provided that will function in cryogenic or cryogenic zero gravity environments to selectively block radiation such as light from passing through a window to a target object such as a mirror or detector located inside a cryogenic container such as a dewar. The mechanism includes a shutter paddle blade that is moved by an electromagnetically actuated torquing device between an open position where the target object is exposed to ambient radiation or light and a closed position where the shutter paddle blade shields the ambient radiation or light from the target object. The purpose of the shuttering device is to prevent the mirror or other target object from being directly exposed to radiation passing through the window located on the side wall of the dewar, thereby decreasing or eliminating any temperature gradient that would occur within the target object due to exposure to the radiation. A special nylon bearing system is utilized to prevent the device from binding during operation and the paddle blade is also thermally connected to a reservoir containing cryogen to further reduce the internal temperature
A PARAMETRIC INVESTIGATION OF THE LUNAR-ORBIT-RENDEZVOUS SCHEME
Lunar orbit rendezvous scheme - mission analysi
NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 9: Information intermediaries and the transfer of aerospace Scientific and Technical Information (STI): A report from the field
From the NASA/DOD survey data, there can be no way of inferring what strategy for knowledge transfer is best; indeed, given the fact that the respondents were all presumably well qualified professionals, the data tend to call into serious question the idea that any one model might meet the needs of more than a distinct minority of possible users. The evidence to date appears to reinforce the concept that different information environments take many different shapes, and interact with each other and with formal data transmission sources in many different and equally valuable ways. Any overall strategy for improving the effectiveness and efficiency of scientific and technical information sharing must take this divergence into account, and work toward the creation of systems that reinforce true interactive knowledge utilization rather than simply disseminating data
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