5 research outputs found
A novel spatial and stochastic model to evaluate the within- and between-farm transmission of classical swine fever virus. I. General concepts and description of the model
Full text linkA Theoretical Model of Long Rossby Waves in the Southern Ocean and Their Interaction with Bottom Topography
No full textMathematical formulation and validation of the Be-FAST model for Classical Swine Fever Virus spread between and within farms
No full textBoehmite Derived γ-Alumina System. 1. Structural Evolution with Temperature, with the Identification and Structural Determination of a New Transition Phase, γ‘-Alumina
No full textThe size of the proton From the Lamb-shift in muonic hydrogen
No full textThe root-mean-square (rms) charge radius r_p of the proton has so far been known only with a surprisingly low precision of about 1% from both electron scattering and precision spectroscopy of hydrogen. We have recently determined r_p
by means of laser spectroscopy of the Lamb shift in the exotic “muonic hydrogen” atom. Here, the muon, which is the 200 times heavier cousin of the electron, orbits the proton with a 200 times smaller Bohr radius. This enhances the sensitivity to the proton’s finite size tremendously. Our new value r_p = 0.84184 (67) fm is ten times more precise than the generally accepted CODATA-value, but it differs by 5 standard deviations from it. A lively discussion about possible solutions to the “proton size puzzle” has started. Our measurement, together with precise measurements of
the 1S–2S transition in regular hydrogen and deuterium, also yields improved values of the Rydberg constant, R_∞ = 10,973,731.568160 (16) m^−1
