190,975 research outputs found
Chiral Meson Physics at Two Loops
An overview of Chiral Perturbation Theory calculations in the mesonic sector
at the two Loop level is given. Discussed in some detail are the partially
quenched case relevant for lattice QCD, the general fitting procedures and
, scattering as well as the determination of and
decays.Comment: 7 pages, Invited plenary talk presented at the 19th European Few-Body
conference, Groningen, The Netherlands, August 23-27, 200
Vector two-point functions in finite volume using partially quenched chiral perturbation theory
We calculate vector-vector correlation functions at two loops using partially
quenched chiral perturbation theory including finite volume effects and twisted
boundary conditions. We present expressions for the flavor neutral cases and
the flavor charged case with equal masses. Using these expressions we give an
estimate for the ratio of disconnected to connected contributions for the
strange part of the electromagnetic current. We give numerical examples for the
effects of partial quenching, finite volume and twisting and suggest the use of
different twists to check the size of finite volume effects. The main use of
this work is expected to be for lattice QCD calculations of the hadronic vacuum
polarization contribution to the muon anomalous magnetic moment.Comment: 31 pages, some sentences added regarding partial twisting,
reformatted equations in appendix to make them more legibl
Chiral Perturbation Theory at Finite Volume and/or with Twisted Boundary Conditions
In this talk we discuss a number of ChPT calculations relevant for lattice
QCD. These include the finite volume corrections at two-loop order for masses
and decay constants. The second part is about hadronic vacuum polarization
where we present the two-loop ChPT estimate for the disconnected and strange
quark contributions. We also present the finite volume corrections at two-loop
order. The final part is the one-loop finite volume with twisted boundary
conditions contribution to and the full amplitudeComment: 7 pages, talk presented at 34th annual International Symposium on
Lattice Field Theory, 24-30 July 2016, University of Southampton, U
A web-based tool to design and analyze single- and double-stage acceptance sampling plans
Acceptance sampling plans are used to determine whether production lots can be accepted or rejected. Existing tools only provide a limited functionality for the two-point design and the risk analysis of such plans. In this article, a web-based tool is presented to study single- and double-stage sampling plans. In contrast to existing solutions, the tool is an interactive applet that is freely available. Analytic properties are derived to support the development of search strategies for the design of double-stage sampling plans that are more efficient and accurate in comparison with existing routines. Several case studies are presented
Scalar Kinetic Mixing and the Renormalization Group
Quantum field theories containing scalar fields with equal quantum numbers
allow for a mixed kinetic term in the Lagrangian. It has been argued that this
mixing must be taken into consideration when performing renormalization group
(RG) analyses of such a theory. However, from the fact that scalar kinetic
mixing does not correspond to a physical observable, we show that no extra
parameters need to be introduced. Using a toy model, we explicitly derive the
1-loop RG equations (RGEs) in three different renormalization schemes to
demonstrate how this issue can be dealt with. In schemes without kinetic
mixing, either the fields mix during renormalization to produce non-diagonal
anomalous dimensions or the RGEs explicitly depend on the scalar masses.
Finally, we show how the different schemes are related to each other by scale
dependent field redefinitions.Comment: 7 pages, journal versio
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