15,338 research outputs found
The Influence of High-Energy Lithium Ion Irradiation on Electrical Characteristics of Silicon and GaAs Solar Cells
Space-grade Si and GaAs solar cells were irradiated with 15 & 40 MeV Li ions.
Illuminated (AM0 condition) and unilluminated I-V curves reveal that the effect
of high-energy Li ion irradiation has produced similar effects to that of
proton irradiation. However, an additional, and different, defect mechanism is
suggested to dominate in the heavier-ion results. Comparison is made with
proton-irradiated solar-cell work and with non-ionizing energy-loss (NIEL)
radiation-damage models.Comment: 8 pages, 12 figures, Data presented at 2006 NSREC, Final Version to
be published in IEEE Transactions on Nuclear Science, 53, NO. 6, December
2006. Index Terms: GaAs, Ion-irradiation, Lithium, NIEL, Photovoltaic cells,
Radiation effects, Silico
Bright gap solitons of atoms with repulsive interaction
We report on the first experimental observation of bright matter-wave
solitons for 87Rb atoms with repulsive atom-atom interaction. This counter
intuitive situation arises inside a weak periodic potential, where anomalous
dispersion can be realized at the Brillouin zone boundary. If the coherent
atomic wavepacket is prepared at the corresponding band edge a bright soliton
is formed inside the gap. The strength of our system is the precise control of
preparation and real time manipulation, allowing the systematic investigation
of gap solitons.Comment: 4 pages, 4 figure
Indian Schistosomes: A Need for Further Investigations
India is uniquely positioned with regard to schistosomes and schistosomiasis—discovering seven new mammalian species with the existence of three more schistosome species: Orientobilharzia turkestanicum, O. harinasutai, and Schistosoma haematobium(?). An endemic focus of urinary schistosomiasis was reported from Gimvi village of Ratnagiri, Maharashtra with infrequent occurrence of schistosome eggs in human stools. Cercarial dermatitis has been reported to be more abundant in rural population using ponds, tanks, and so forth, for their domestic purposes. Few dermatitis cases were tested positive by CHR. Schistosome antigen was also detected in urine of five cases suggesting existence of active schistosomiasis in India. Nevertheless, human kind does not appear to be the usual host for Indian schistosomes in contrast to S. haematobium, S. mansoni, or S. japonicum. Various reasons for this phenomenon are discussed including evolution of Indian schistosomes, immune mechanisms, and environmental conditions. These and other aspects such as seasonal effect on the prevalence, snail infectivity, heterologous mating, existence of hybrids, and number of schistosomes in heterologous infections need further investigations with application of molecular techniques. Joint efforts by the national as well as international scientific community would be much more rewarding for better understanding of the parasite and the infection
Two Photon Contribution to Polarization in
Short distance physics involving virtual top and charm quarks contributes to
(and ) polarization in the decay . Measurement of the parity violating asymmetry , where and are the rates
to produce right and left-handed , may provide valuable information on
the unitarity triangle. The parity violating asymmetry also gets a contribution
from Feynman diagrams with two photon intermediate states. We estimate this two
photon contribution to the asymmetry and discuss briefly the two photon
contribution to time reversal odd asymmetries that involve both the and
polarizations.Comment: (19 pages, 5 figures available on request. Uses phyzzx),
CALT-68-1798, UCSD/PTH 92-2
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