Fitting Precision Electroweak Data with Exotic Heavy Quarks

The 1999 precision electroweak data from LEP and SLC persist in showing some slight discrepancies from the assumed standard model, mostly regarding $b$ and $c$ quarks. We show how their mixing with exotic heavy quarks could result in a more consistent fit of all the data, including two unconventional interpretations of the top quark.Comment: 7 pages, no figure, 2 typos corrected, 1 reference update

Empirically Charting Dynamical Chiral Symmetry Breaking

We provide a snapshot of recent progress in hadron physics made using QCD's Dyson-Schwinger equations, reviewing the generation of a quark anomalous chromomagnetic moment, which may explain the longstanding puzzle of the $a_1$-$\rho$ mass splitting, and the form of the pion and kaon valence-quark parton distribution functions.Comment: 6 pages, 1 figure, 1 table. Contribution to the proceedings of "Achievements and New Directions in Subatomic Physics: Workshop in Honour of Tony Thomas' 60th Birthday," Special Centre for the Subatomic Structure of Matter, Adelaide, South Australia, February 15 - February 19, 2010

Experimental evaluation of atmospheric effects on radiometric measurements using the EREP of Skylab

There are no author-identified significant results in this report

A Study of the LEP and SLD Measurements of AbA_b

A systematic study is made of the data dependence of the parameter $A_{\rm{b}}$, that, since 1995, has shown a deviation from the Standard Model prediction of between 2.4 and 3.1 standard deviations. Issues addressed include: the effect of particular measurements, values found by individual experiments, LEP/SLD comparison, and the treatment of systematic errors. The effect, currently at the 2.4$\sigma$ level, is found to vary in the range from 1.7$\sigma$ to 2.9$\sigma$ by excluding marginal or particularly sensitive data. Since essentially the full LEP and SLD Z decay data sets are now analysed the meaning of the deviation, (new physics, or marginal statistical fluctuation) is unlikely to be given by the present generation of colliders.Comment: 15 pages 7 figures 7 table

Dressed-quark anomalous magnetic moments

Perturbation theory predicts that a massless fermion cannot possess a measurable magnetic moment. We explain, however, that the nonperturbative phenomenon of dynamical chiral symmetry breaking generates a momentum-dependent anomalous chromomagnetic moment for dressed light-quarks, which is large at infrared momenta; and demonstrate that consequently these same quarks also possess an anomalous electromagnetic moment with similar magnitude and opposite sign.Comment: 4 pages, 1 2-panel figur