29,424 research outputs found
Electric arc device for heating gases Patent
Electric arc device for minimizing electrode ablation and heating gases to supersonic or hypersonic wind tunnel temperature
A Hypergeometric Mean Value
Generalization of hypergeometric mean value from hypergeometric function without loss of homogeneity - derivation and properties of hypergeometric mean valu
Resonance Region Structure Functions and Parity Violating Deep Inelastic Scattering
The primary motive of parity violating deep inelastic scattering experiments
has been to test the standard model, particularly the axial couplings to the
quarks, in the scaling region. The measurements can also test for the validity
of models for the off-diagonal structure functions in the resonance region. The off-diagonal structure functions are
important for the accurate calculation of the -box correction to the
weak charge of the proton. Currently, with no data to determine
directly, models are constructed by modifying
existing fits to electromagnetic data. We present the asymmetry value for
deuteron and proton target predicted by several different models, and demonstrate that there are notable disagreements.Comment: 6 pages, 3 figures. New version contains additional descriptions of
competing structure function model
New Physics and the Proton Radius Problem
Background: The recent disagreement between the proton charge radius
extracted from Lamb shift measurements of muonic and electronic hydrogen
invites speculation that new physics may be to blame. Several proposals have
been made for new particles that account for both the Lamb shift and the muon
anomalous moment discrepancies. Purpose: We explore the possibility that new
particles' couplings to the muon can be fine-tuned to account for all
experimental constraints. Method: We consider two fine-tuned models, the first
involving new particles with scalar and pseudoscalar couplings, and the second
involving new particles with vector and axial couplings. The couplings are
constrained by the Lamb shift and muon magnetic moments measurements while mass
constraints are obtained by kaon decay rate data. Results: For the
scalar-pseudoscalar model, masses between 100 to 200 MeV are not allowed. For
the vector model, masses below about 200 MeV are not allowed. The strength of
the couplings for both models approach that of electrodynamics for particle
masses of about 2 GeV. Conclusions: New physics with fine tuned couplings may
be entertained as a possible explanation for the Lamb shift discrepancy.Comment: 6 pages, 6 figures, v2 contains revised comment on competing model of
Lamb Shift discrepanc
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