Search for vector dark matter in microwave cavities with Rydberg atoms

We propose a novel experiment to search for dark matter, based on the application of an electric field inside a microwave cavity and electrometry using Rydberg atoms. We show that this kind of experiment could be extremely useful for detecting specific dark matter candidates, namely massive vector fields coupled to the photon field, more commonly known as dark photons. Such a massive vector field is a good candidate for dark matter. Using realistic experimental parameters we show that such an experiment could improve the current constraint on the coupling constant of the dark photons to Standard Model photons in the 1 to 10~$\mu$eV mass range, with the possibility of tuning the maximum sensitivity via the cavity size. The main limiting factors on the sensitivity of the experiment are the amplitude stability of the applied field and the measurement uncertainty of the electric field by the atoms.Comment: 14 pages, 4 figure

Village Baseline Study: Site Analysis Report for Yatenga – Tougou, Burkina Faso

The village baseline study of Kononga village in the CCAFS site Yatenga-Tougou in Burkina Faso took place from 19th to 21st July 2011. Focus group discussions were conducted separately for men and women. Male and female participants believe that the natural resources in the village are deteriorating due to population increase and labour shortages related to the exodus of young people to gold mining sites. The village’s vision of the future includes more productive and fertile farmland, a denser forest, deeper and wider water reservoirs, and more boreholes. The men identified 21 organisations in the village, including 9 operating at the community level, while women identified 17 organisations, 10 of which operate at the community level. Men are considered the most important personal source of information in the village. The regional directorate for agriculture, hydrology and fishery resources (DRAHRA) is the single most relevant institutional source of climate and weather information for both male and female participants. Men and women gather information from outside the village via radio broadcasting and particularly Radio “Voix du paysan” (Voice of the Farmer). The market is the most important channel of information access for women. Women have a substantial role in agriculture and livestock production, as well as natural resource management but they have limited access to land or to improved technology or equipment, and few training opportunities

Village Baseline Study: Site Analysis Report for Kaffrine – Kaffrine, Senegal

The village baseline study of Toune Mosquée village in the CCAFS benchmark site Kaffrine in Senegal took place from June 2 to 4, 2011. Natural resources in the village are in a progressive state of degradation. The ‘protected’ forest has almost disappeared, the soils have low fertility and are degraded, and crop production is not sufficient to meet the food needs of a family throughout the year. Families must buy food to fill the gap in production. For that they harvest and sell forest products, which creates a vicious cycle of resource degradation. The male and female groups identified 35 organisations operating in the village including informal groups, state services, associations, NGOs and Muslim brotherhoods. While 18 of those work on food security issues, only 4 are involved in the management and protection of natural resources. Very few agricultural extension and training opportunities target women despite the women’s significant role in agriculture and livestock production. Women obtain information on livestock feeding techniques from people and organisations such as the horticultural project, women’s associations, and water and forest services. Men get information on soil inputs and soil fertility management from other farmers, organisations, radio and television, and from community leaders, notably the office of the village chief and the mosque on Fridays. The radio is the form of media most commonly used by the women but few women own a radio

Understanding innovation platform effectiveness through experiences from west and central Africa

Innovation platforms (IPs) are a way of organizing multistakeholder interactions, marshalling ideas, people and resources to address challenges and opportunities embedded in complex settings. The approach has its roots in theories of complexity, the concept of innovation systems and practices of participatory action research. IPs have been widely adopted across Africa and beyond in recent years as a “must have” tool in a range of “for development” modes of agricultural research. Our experiences with establishing and facilitating nine IPs in local settings in west and central Africa contribute to understanding factors that impact on their effectiveness. The nine IPs were variously focused on developing dairy, crop and/or meat value chains by strengthening mixed crop-livestock production systems or seed systems. Using case study methods, we identified variables that contribute to explaining the performance of these IPs in relation to six domains of change in the agricultural system and the sustainability of changes. Thematic analysis was guided by a conceptual framework which grouped variables into four categories (context, structure, conduct, and process) that interact to influence IP performance. Stronger market connections and value chains were generated through some of these IPs but the most prevalent changes overall were in farm productivity and technical knowledge of producers. The structures evolved in some IPs, akin to those of producer collectives, suggested they were filling an institutional gap locally. The effect of the IPs on deeper level institutions that influence agricultural systems and food security was modest, constraining prospects for the IPs to generate impact at scale. Impacts from the IPs on research and development organisations were uncommon but had transformative significance. Our conceptual framework did not offer optimal guidance to understanding how the many variables that contributed to performance of these IPs combined and sequenced, but the pattern of interactions was consistent with increased social capital being the prime mediator for change. Achieving greater prospects for transformational change and impact at scale warrants at least equal attention to three other interconnected change pathways: through markets, institutions and innovation capacity. Important factors for increased impact are individuals and organisations with capacity to purposefully build and manage inter-organisational and cross-scale networks, early diagnostic studies of the institutional landscape, and adaptive processes of critical reflection and learning that continue beyond the short term

Search for vector dark matter in microwave cavities with Rydberg atoms

International audienceWe propose a novel experiment to search for dark matter, based on the application of an electric field inside a microwave cavity and electrometry using Rydberg atoms. We show that this kind of experiment could be extremely useful for detecting specific dark matter candidates, namely massive vector fields coupled to the photon field, more commonly known as dark photons. Such a massive vector field is a good candidate for dark matter. Using realistic experimental parameters we show that such an experiment could improve the current constraint on the coupling constant of the dark photons to Standard Model photons in the 1 to 10~$\mu$eV mass range, with the possibility of tuning the maximum sensitivity via the cavity size. The main limiting factors on the sensitivity of the experiment are the amplitude stability of the applied field and the measurement uncertainty of the electric field by the atoms

Role of the active layer thickness on the sensitivity of WO<SUB align="right">3 gas sensors

International audienc

Search for vector dark matter in microwave cavities with Rydberg atoms

International audienceWe propose a novel experiment to search for dark matter, based on the application of an electric field inside a microwave cavity and electrometry using Rydberg atoms. We show that this kind of experiment could be extremely useful for detecting specific dark matter candidates, namely massive vector fields coupled to the photon field, more commonly known as dark photons. Such a massive vector field is a good candidate for dark matter. Using realistic experimental parameters we show that such an experiment could improve the current constraint on the coupling constant of the dark photons to Standard Model photons in the 1 to 10~$\mu$eV mass range, with the possibility of tuning the maximum sensitivity via the cavity size. The main limiting factors on the sensitivity of the experiment are the amplitude stability of the applied field and the measurement uncertainty of the electric field by the atoms