133 research outputs found
Analytical eighth-order light-by-light QED contributions from leptons with heavier masses to the anomalous magnetic moment of electron
The important consequences of the recent results of the numerical evaluations
of eighth and tenth order QED contributions to the anomalous magnetic moment of
electron are commented. The correctness of the results of the numerical
evaluation of new eighth order QED corrections to the electron anomaly are
supported by the demonstration of their consistency with the new analytical
expressions for the QED contributions to from the diagrams with
fourth-order light-by-light scattering muon and tau-lepton loops. The
consistency of the similar results are demonstrated in the case of eighth order
massive dependent contribution to the muon anomalous magnetic moment.Comment: 6 pages, LaTeX, The preliminary version of the longer work with the
same title was registered as CERN Preprint during the visit to Theory
Division of CERN in January of 201
Fivebrane Lagrangian with Loop Corrections in Field-Theory Limit
Equations of motion and the lagrangian are derived explicitely for Dual D=10,
N=1 Supergravity considered as a field theory limit of a Fivebrane. It is used
the mass-shell solution of Heterotic String Bianchi Identites obtained in the
2-dimensional -model two-loop approximation and in the tree-level
Heterotic String approximation. As a result the Dual Supergravity lagrangian is
derived in the one-loop Five-Brane approximation and in the lowest
6-dimensional -model approximaton.Comment: 21 page
Reconsidered estimates of the 10th order QED contributions to the muon anomaly
The problem of estimating the 10th order QED corrections to the muon
anomalous magnetic moment is reconsidered. The incorporation of the recently
improved contributions to the and - corrections to
within the renormalization-group inspired scheme-invariant approach
leads to the estimate . It is in good
agreement with the estimate , obtained
by Kinoshita and Nio from the numerical calculations of 2958 10-th order
diagrams, which are considered to be more important than the still uncalculated
6122 10th-order -dependent vertex graphs, and 12672 5-loop
diagrams, responsible for the mass-independent constant contribution both to
and . This confirms Kinoshita and Nio guess about dominance of
the 10-th order diagrams calculated by them. Comparisons with other estimates
of the - contributions to , which exist in the literature,
are presented.Comment: 19 pages, LaTeX, some misprints in the text and literature corrected.
Results unchaged, to appear in Phys.Rev.
Individual and Multi Vortex Pinning in Systems with Periodic Pinning Arrays
We examine multi and individual vortex pinning in thin superconductors with
periodic pinning arrays. For multi-vortex pinning we observe peaks in the
critical current of equal magnitude at every matching field, while for
individual vortex pinning we observe a sharp drop in the critical current after
the first matching field in agreement with experiments. We examine the scaling
of the critical current at commensurate and incommensurate fields for varied
pinning strength and show that the depinning force at incommensurate fields
decreases faster than at the commensurate fields.Comment: 4 figuure
Tracking Rates of Forest Disturbance and Associated Carbon Loss in Areas of Illegal Amber Mining in Ukraine Using Landsat Time Series
Mapping forest disturbance is crucial for many applications related to decision-making for sustainable forest management. This study identified the effect of illegal amber mining on forest change and accumulated carbon stock across a study area of 8125.5 ha in northern Ukraine. Our method relies on the Google Earth Engine (GEE) implementation of the Landsat-based Detection of Trends in Disturbance and Recovery (LandTrendr) temporal segmentation algorithm of Landsat time-series (LTS) to derive yearly maps of forest disturbance and recovery in areas affected by amber extraction operations. We used virtual reality (VR) 360 interactive panoramic images taken from the sites to attribute four levels of forest disturbance associated with the delta normalized burn ratio (dNBR) and then calculated the carbon loss. We revealed that illegal amber extraction in Ukraine has been occurring since the middle of the 1990s, yielding 3260 ha of total disturbed area up to 2019. This study indicated that the area of forest disturbance increased dramatically during 2013–2014, and illegal amber operations persist. As a result, regrowth processes were mapped on only 375 ha of total disturbed area. The results were integrated into the Forest Stewardship Council® (FSC®) quality management system in the region to categorize Forest Management Units (FMUs) conforming to different disturbance rates and taking actions related to their certification status. Moreover, carbon loss evaluation allows the responsible forest management systems to be streamlined and to endorse ecosystem service assessment
ILCRoot Tracker and Vertex Detector Hits Response to MARS15 Simulated Backgrounds in the Muon Collider
Abstract Results from a simulation of the background for a muon collider, and the hits response of a silicon tracking detector to this backgroundare presented.The backgroundcausedbydecaysofthe750 GeV/ c beam μ + and μ − was simulated using the MARS15 program, which included the infrastructure of the beam line elements near the detector and the 10 ∘ nozzles that shield the detector from this background. The ILCRoot framework, along with the Geant4 program, was used to simulate the hits response of the tracker and vertex silicon detectors to the muon-decay background remaining after the shielding nozzles. Results include the hit distributions in these detectors, the fractions of type-specific background particles producing these hits and illustrate the use of timing of the hits to suppress the muon beam background
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