Spectral line shape modeling and ion temperature fluctuations in tokamak edge plasmas

In this work, we use a passive advection model for ion temperature fluctuations, in order to investigate their effects on Doppler Spectral line shapes. The relevance of the model is discussed in the framework of the Braginskii equations, and the subsequent Probability Density Function evaluation relies on results obtained in neutral fluids. The resulting Doppler line profiles are shown to exhibit characteristic exponential tails.Comment: 6 pages, 2 figures, to be published in Contributions to Plasma Physic

Governing through freedom, ruling at a distance: neoliberal governmentality and the new aid architecture in the AIDS response in Malawi

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In this thesis, I critically analyse power relations between donors and the government of Malawi (GoM) under the new aid architecture and argue that this new configuration represents a shift away from domination, with donors attempting to impose policies, and towards more subtle interactions, through which donors seek to transform the GoM into a self-disciplined, entrepreneurial, neoliberal subject by shaping its aspirations and promoting specific norms of conduct, ‘truths’ and policy-related techniques. The research focuses on funding for AIDS and draws on forty interviews with representatives from the GoM, donors and civil society, conducted in Malawi 2008, as well as discursive analysis of secondary sources. I use Foucault’s concept of governmentality, a form of productive power focused on the care of the population and working through individuals’ subjectivities, and extend it to the relation between donors and the GoM. I show that the agency of the GoM is both elicited by the principle of country ownership, and re-worked through the increased involvement of donors in the policy sphere. I explore how these interactions are legitimised by a discourse that presents donors and the GoM as equals, while casting the GoM as technically deficient and requiring donors’ intervention. I analyse how donors instrumentalise dialogue with the GoM to instil an ethos of self-responsibility.I also investigate how AIDS funding has been made reliant on public financial management reforms, which re-code social domains according to an economic logic, by subordinating government activities to macroeconomic imperatives and creating new undemocratic accountabilities based on market rationalities. I argue that by restructuring the GoM according to this neoliberal rationality, the new aid architecture has programmatic effects, allowing donors to rule at a distance. I also examine avenues for resistance, particularly the potential residing in the intrinsic contradictions of this rationality.2008 Postgraduate Travel Award awarded by DARG

Kinetic equations for Stark line shapes

The BBGKY formalism is revisited in the framework of plasma spectroscopy. We address the issue of Stark line shape modeling by using kinetic transport equations. In the most simplified treatment of these equations, triple correlations between an emitter and the perturbing charged particles are neglected and a collisional description of Stark effect is obtained. Here we relax this assumption and retain triple correlations using a generalization of the Kirkwood truncature hypothesis to quantum operator. An application to hydrogen lines is done in the context of plasma diagnostic, and indicates that the neglect of triple correlations can lead to a significant overestimate of the line width.Comment: 13 pages, 1 figur

Accuracy of impact broadening models in low-density magnetized hydrogen plasmas

International audienceThe impact approximation used in the modelling of Stark profiles is examined when a magnetic field is present. Motivated by tokamak plasma spectroscopy, we calculate line shapes and $S$-matrix elements for the first Lyman lines of hydrogen with two models proposed for retaining simultaneously Stark and Zeeman effects in the impact limit. An evaluation of the accuracy of the two approaches is made with the help of a numerical simulation

Invisible experiences: Understanding the choices and needs of university students with dependent children

This paper analyses the results of a research project on the experiences and learning needs of students with dependent children in a 1960s university. The findings are based on semi-structured interviews with university services and academic staff, as well as a questionnaire survey among students with dependent children and follow-up in-depth interviews with a sample of 18 of these students. The paper shows that, for those surveyed, future employment opportunities and being a role model for their children were the main motivations for entering higher education and that their choice of university was highly spatially restricted by their caring responsibilities. It also discusses the main issues students faced once at university, including time and timing, finance, childcare, confidence, sense of belonging and skills. The paper highlights how gender and other biographical characteristics influence parents' experiences and includes suggestions for lessening the barriers they face while at university

‘Lived bodies’ and the neoliberal city – a case study of vulnerability in London

This is an Accepted Manuscript of an article published by Taylor & Francis in Gender, Place and Culture on 11/10/2017, available online: https://www.tandfonline.com/doi/full/10.1080/0966369X.2017.1382450U Turn Women’s Projec

The liminality of training spaces: Places of private/public transitions

This paper draws upon research, conducted for the London West Learning and Skills Council, on the training experiences of women with dependent children. One of the striking revelations of the research, we suggest, is the way in which training spaces are used and perceived by women, which are often at odds with government intentions. To help make sense of women’s use of and motivation for training we utilise the concept of ‘liminality’ and the private/public imbrication to explain the ways in which women use, or are discouraged from using, training spaces. Further, how the varied and multiple uses women in our research have put training to in their own lives has encouraged us to rethink the relationship between the private and the public more generally. In the light of this, we suggest that training and the places in which training take place, have been neglected processes and spaces within feminist geography and might usefully be explored further to add to an extensive literature on women’s caring and domestic roles and their role in the paid workplace

3D structure and dynamics of filaments in turbulence simulations of WEST diverted plasmas

International audienceWe study the effect of a diverted magnetic geometry on edge plasma turbulence, focusing on the three-dimensional structure and dynamics of filaments, also called blobs, in simulations of the WEST tokamak, featuring a primary and secondary X-point. For this purpose, in addition to classical analysis techniques, we apply here a novel fully 3D Blob Recognition And Tracking (BRAT) algorithm, allowing for the first time to resolve the three-dimensional structure and dynamics of the blobs in a turbulent 3D plasma featuring a realistic magnetic geometry. The results are tested against existing theoretical scalings of blob velocity [Myra et al, Physics of Plasmas 2006]. The complementary analysis of the 3D structure of the filaments shows how they disconnect from the divertor plate in the vicinity of the X-points, leading to a transition from a sheath-connected regime to the ideal-interchange one. Furthermore, the numerical results show non-negligible effects of the turbulent background plasma: approximately half of the detected filaments are involved in mutual interactions, eventually resulting in negative radial velocities, and a fraction of the filaments is generated by turbulence directly below the X-point