1,257 research outputs found
Clockwork graviton contributions to muon
The clockwork mechanism for gravity introduces a tower of massive graviton
modes, "clockwork gravitons," with a very compressed mass spectrum, whose
interaction strengths are much stronger than that of massless gravitons. In
this work, we compute the lowest order contributions of the clockwork gravitons
to the anomalous magnetic moment, , of muon in the context of extra
dimensional model with a five dimensional Planck mass, . We find that the
total contributions are rather insensitive to the detailed model parameters,
and determined mostly by the value of . In order to account for the
current muon anomaly, should be around , and the
size of the extra dimension has to be quite large, m.
For , the clockwork graviton contributions are too small
to explain the current muon anomaly. We also compare the clockwork
graviton contributions with other extra dimension models such as
Randall-Sundrum models or large extra dimension models. We find that the
leading contributions in the small curvature limit are universal, but the
cutoff-independent subleading contributions vary for different background
geometries and the clockwork geometry gives the smallest subleading
contributions.Comment: 14 pages, 4 figures: v3 minor corrections, to appear in PR
The Journal of Gynecologic Oncology and the Asian Society of Gynecologic Oncology: the history, the present and the future
Can disclosure of scoring rubric for basic clinical skills improve objective structured clinical examination?
Electromagnet Weight Reduction in a Magnetic Levitation System for Contactless Delivery Applications
This paper presents an optimum design of a lightweight vehicle levitation electromagnet, which also provides a passive guide force in a magnetic levitation system for contactless delivery applications. The split alignment of C-shaped electromagnets about C-shaped rails has a bad effect on the lateral deviation force, therefore, no-split positioning of electromagnets is better for lateral performance. This is verified by simulations and experiments. This paper presents a statistically optimized design with a high number of the design variables to reduce the weight of the electromagnet under the constraint of normal force using response surface methodology (RSM) and the kriging interpolation method. 2D and 3D magnetostatic analysis of the electromagnet are performed using ANSYS. The most effective design variables are extracted by a Pareto chart. The most desirable set is determined and the influence of each design variable on the objective function can be obtained. The generalized reduced gradient (GRG) algorithm is adopted in the kriging model. This paper’s procedure is validated by a comparison between experimental and calculation results, which shows that the predicted performance of the electromagnet designed by RSM is in good agreement with the simulation results
Cooling of young neutron stars and dark gauge bosons
The standard cooling scenario in the presence of nucleon superfluidity fits rather well to the observation of the neutron stars. It implies that the stellar cooling arguments could place a stringent constraint on the properties of novel particles. We study in particular the cooling rate induced by dark gauge bosons for very young neutron stars: remnants of Cassiopeia A and SN1987A. The cooling is dominantly contributed either by the nucleon pair breaking and formation in the core or by the electron bremsstrahlung in the crust, depending on the age of the stars and the form of the couplings. We compute how much the cooling curve of the young neutron stars could be modified by the extra dark gauge boson emission and obtain the bound for the dark gauge boson when its mass is lower than ; for the dark photon we find the mixing parameter times its mass and for the gauge boson its coupling to nucleons and electrons . We also discuss the possibility that the rapid cooling of Cas A might provide a hint for the existence of the gauge boson
Longitudinal analysis of the effect of academic failure tolerance on academic achievement fluctuation in medical school students
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