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The hyperon puzzle, the observation that the two-solar-mass neutron stars existence is hardly explained by all models predicting the appearance of hyperons in the neutron star core is currently one of the unsolved key issues in the physics of compact stars. An experimental study of the reaction (e,e′K) on 40Ca 48Ca nuclei to study the isospin dependence of hyperon dynamics has been proposed, by the Jefferson lab hypernuclear collaboration, and approved by the Jefferson Lab (JLab) PAC. This paper describes a proposal to make a complementary study by extending it to 208Pb, whose properties largely reflects those of the uniform nuclear matter present in the interior of the neutron stars making it the ideal one for this task. [ABSTRACT FROM AUTHOR]

High power liquid hydrogen (LH2) targets, up to 850 W, have been widely used at Jefferson Lab for the 6 GeV physics program. The typical luminosity loss of a 20 cm long LH2 target was 20% for a beam current of 100 μA rastered on a square of side 2 mm on the target. The 35 cm long, 2500 W LH2 target for the Qweak experiment had a luminosity loss of 0.8% at 180 μA beam rastered on a square of side 4 mm at the target. The Qweak target was the highest power liquid hydrogen target in the world and with the lowest noise figure. The Qweak target was the first one designed with CFD at Jefferson Lab. A CFD facility is being established at Jefferson Lab to design, build and test a new generation of low noise high power targets. [ABSTRACT FROM AUTHOR]

The NPDGamma collaboration has constructed and commissioned an apparatus on flight path 12 at LANSCE to measure with a high precision, 5×10-9, the small parity-violating gamma-ray asymmetry, Aγ, in polarized neutron capture on protons. This asymmetry can be determined unambiguously the weak pion-nucleon coupling constant. To study the hadronic weak interaction at low energy, the collaboration has used the NPDGamma apparatus to measure parity-violating gamma-ray asymmetries in compound nuclei with cold neutrons. Using the statistical model of compound nuclei and spectroscopic information of the target nuclei, we can set upper limit on the spreading width of the hadronic weak interaction for intermediate-mass nuclei. We describe the experiment and the preliminary results of measured gamma-ray asymmetries of Al, Sc, Ti, Mn, and Co. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]