23 research outputs found
Dark Force Detection in Low Energy e-p Collisions
We study the prospects for detecting a light boson X with mass m_X < 100 MeV
at a low energy electron-proton collider. We focus on the case where X
dominantly decays to e+ e- as motivated by recent "dark force" models. In order
to evade direct and indirect constraints, X must have small couplings to the
standard model (alpha_X 10 MeV).
By comparing the signal and background cross sections for the e- p e+ e- final
state, we conclude that dark force detection requires an integrated luminosity
of around 1 inverse attobarn, achievable with a forthcoming JLab proposal.Comment: 38 pages, 19 figures; v2, references adde
Consistent truncations of supergravity and 1/2-BPS RG flows in 4d SCFTs
With the purpose of holographically describing flows from a large family of
four dimensional and conformal field theories, we
discuss truncations of seven dimensional supergravity to five dimensions. We
write explicitly the reduced gauged supergravity and find BPS equations for
simple configurations. Lifting these flows to eleven dimensions or Massive IIA
supergravity, we present string duals to RG flows from strongly coupled
conformal theories when deformed by marginal and/or relevant operators. We
further discuss observables common to infinite families of and
QFTs in this context.Comment: 28 pages plus appendixes. JHEP versio
Establishment of a large semi-field system for experimental study of African malaria vector ecology and control in Tanzania
<b>Background:</b>
Medical entomologists increasingly recognize that the ability to make inferences between laboratory experiments of vector biology and epidemiological trends observed in the field is hindered by a conceptual and methodological gap occurring between these approaches which prevents hypothesis-driven empirical research from being conducted on relatively large and environmentally realistic scales. The development of Semi-Field Systems (SFS) has been proposed as the best mechanism for bridging this gap. Semi-field systems are defined as enclosed environments, ideally situated within the natural ecosystem of a target disease vector and exposed to ambient environmental conditions, in which all features necessary for its life cycle completion are present. Although the value of SFS as a research tool for malaria vector biology is gaining recognition, only a few such facilities exist worldwide and are relatively small in size (< 100 m<sup>2</sup>).
<b>Methods:</b>
The establishment of a 625 m<sup>2</sup> state-of-the-art SFS for large-scale experimentation on anopheline mosquito ecology and control within a rural area of southern Tanzania, where malaria transmission intensities are amongst the highest ever recorded, is described.
<b>Results:</b>
A greenhouse frame with walls of mosquito netting and a polyethylene roof was mounted on a raised concrete platform at the Ifakara Health Institute. The interior of the SFS was divided into four separate work areas that have been set up for a variety of research activities including mass-rearing for African malaria vectors under natural conditions, high throughput evaluation of novel mosquito control and trapping techniques, short-term assays of host-seeking behaviour and olfaction, and longer-term experimental investigation of anopheline population dynamics and gene flow within a contained environment that simulates a local village domestic setting.
<b>Conclusion:</b>
The SFS at Ifakara was completed and ready for use in under two years. Preliminary observations indicate that realistic and repeatable observations of anopheline behaviour are obtainable within the SFS, and that habitat and climatic features representative of field conditions can be simulated within it. As work begins in the SFS in Ifakara and others around the world, the major opportunities and challenges to the successful application of this tool for malaria vector research and control are discussed