1,478 research outputs found
Homotopy Lie Superalgebra in Yang-Mills Theory
The Yang-Mills equations are formulated in the form of generalized
Maurer-Cartan equations, such that the corresponding algebraic operations are
shown to satisfy the defining relations of homotopy Lie superalgebra.Comment: LaTeX2e, 10 page
Homotopy Relations for Topological VOA
We consider a parameter-dependent version of the homotopy associative part of
the Lian-Zuckerman homotopy algebra and provide the interpretation of
multilinear operations of this algebra in terms of integrals over certain
polytopes. We explicitly prove the pentagon relation up to homotopy and propose
a construction of higher operations.Comment: 15 pages, 1 figure, typos correcte
Rethinking the Governance and Delivery of the Cohesion Policy Funds:Is the Recovery and Resilience Facility (RRF) a Model?
The Cohesion Policy Funds (CPF) have faced continuous debate about their effectiveness in reaching specified performance objectives, while at the same time advancing broader EU policy goals. The Recovery and Resilience Facility (RRF)’s “performance-based financing” model, where payment is based on the fulfilment of milestones and targets, rather than reimbursement of eligible costs, is sometimes presented as a superior alternative and possible inspiration for the future of the CPF. The RRF model centralises authority in the hands of national governments and promises tighter integration of investment and reforms, with monitoring focusing on results instead of receipts. In this context, it is crucial to understand more precisely how the RRF model differs from that of CPF and how the RRF model has been working out in practice, in order to draw lessons for the future of the CPF, which is the goal of this paper
Rethinking the Governance and Delivery of the Cohesion Policy Funds:Is the Recovery and Resilience Facility (RRF) a Model?
The Cohesion Policy Funds (CPF) have faced continuous debate about their effectiveness in reaching specified performance objectives, while at the same time advancing broader EU policy goals. The Recovery and Resilience Facility (RRF)’s “performance-based financing” model, where payment is based on the fulfilment of milestones and targets, rather than reimbursement of eligible costs, is sometimes presented as a superior alternative and possible inspiration for the future of the CPF. The RRF model centralises authority in the hands of national governments and promises tighter integration of investment and reforms, with monitoring focusing on results instead of receipts. In this context, it is crucial to understand more precisely how the RRF model differs from that of CPF and how the RRF model has been working out in practice, in order to draw lessons for the future of the CPF, which is the goal of this paper
Update on Radiation Dose From Galactic and Solar Protons at the Moon Using the LRO/CRaTER Microdosimeter
The NASA Lunar Reconnaissance Orbiter (LRO) has been exploring the lunar surface and radiation environment since June 2009. In Mazur et al. [2011] we discussed the first 6 months of mission data from a microdosimeter that is housed within the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument onboard LRO. The CRaTER microdosimeter is an early version of what is now a commercially available hybrid that accurately measures total ionizing radiation dose in a silicon target (http://www.teledynemicro.com/product/radiation-dosimeter). This brief report updates the transition from a deep solar minimum radiation environment to the current weak solar maximum as witnessed with the microdosimeter
Visible-Light-Responsive Catalyst Development for Volatile Organic Carbon Remediation Project
Photocatalysis is a process in which light energy is used to 'activate' oxidation/reduction reactions. Unmodified titanium dioxide (TiO2), a common photocatalyst, requires high-energy UV light for activation due to its large band gap (3.2 eV). Modification of TiO2 can reduce this band gap, leading to visible-light-responsive (VLR) photocatalysts. These catalysts can utilize solar and/or visible wavelength LED lamps as an activation source, replacing mercury-containing UV lamps, to create a "greener," more energy-efficient means for air and water revitalization. Recently, KSC developed several VLR catalysts that, on preliminary evaluation, possessed high catalytic activity within the visible spectrum; these samples out-performed existing commercial VLR catalysts
GCR access to the Moon as measured by the CRaTER instrument on LRO
[1] Recent modeling efforts have yielded varying and conflicting results regarding the possibility that Earth\u27s magnetosphere is able to shield energetic particles of \u3e10 MeV at lunar distances. This population of particles consists of galactic cosmic rays as well as energetic particles that are accelerated by solar flares and coronal mass ejections. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard the Lunar Reconnaissance Orbiter is in orbit about the Moon and is thus able to directly test these modeling results. Over the course of a month, CRaTER samples the upstream solar wind as well as various regions of Earth\u27s magnetotail. CRaTER data from multiple lunations demonstrate that Earth\u27s magnetosphere at lunar distances produces no measurable influence on energetic particle flux, even at the lowest energies (\u3e14 MeV protons) where any effect should be maximized. For particles with energies of 14–30 MeV, we calculate an upper limit (determined by counting statistics) on the amount of shielding caused by the magnetosphere of 1.7%. The high energy channel (\u3e500 MeV) provides an upper limit of 3.2%
Beta-gamma systems and the deformations of the BRST operator
We describe the relation between simple logarithmic CFTs associated with
closed and open strings, and their "infinite metric" limits, corresponding to
the beta-gamma systems. This relation is studied on the level of the BRST
complex: we show that the consideration of metric as a perturbation leads to a
certain deformation of the algebraic operations of the Lian-Zuckerman type on
the vertex algebra, associated with the beta-gamma systems. The Maurer-Cartan
equations corresponding to this deformed structure in the quasiclassical
approximation lead to the nonlinear field equations. As an explicit example, we
demonstrate, that using this construction, Yang-Mills equations can be derived.
This gives rise to a nontrivial relation between the Courant-Dorfman algebroid
and homotopy algebras emerging from the gauge theory. We also discuss possible
algebraic approach to the study of beta-functions in sigma-models.Comment: LaTeX2e, 15 pages; minor revision, typos corrected, Journal of
Physics A, in pres
The first cosmic ray albedo proton map of the Moon
[1] Neutrons emitted from the Moon are produced by the impact of galactic cosmic rays (GCRs) within the regolith. GCRs are high-energy particles capable of smashing atomic nuclei in the lunar regolith and producing a shower of energetic protons, neutrons and other subatomic particles. Secondary particles that are ejected out of the regolith become “albedo” particles. The neutron albedo has been used to study the hydrogen content of the lunar regolith, which motivates our study of albedo protons. In principle, the albedo protons should vary as a function of the input GCR source and possibly as a result of surface composition and properties. During the LRO mission, the total detection rate of albedo protons between 60 MeV and 150 MeV has been declining since 2009 in parallel with the decline in the galactic cosmic ray flux, which validates the concept of an albedo proton source. On the other hand, the average yield of albedo protons has been increasing as the galactic cosmic ray spectrum has been hardening, consistent with a disproportionately stronger modulation of lower energy GCRs as solar activity increases. We construct the first map of the normalized albedo proton emission rate from the lunar surface to look for any albedo variation that correlates with surface features. The map is consistent with a spatially uniform albedo proton yield to within statistical uncertainties
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