Renormalization group approach to Sudakov resummation in prompt photon production

We prove the all-order exponentiation of soft logarithmic corrections to prompt photon production in hadronic collisions, by generalizing an approach previously developed in the context of Drell-Yan production and deep-inelastic scattering. We show that all large logs in the soft limit can be expressed in terms of two dimensionful variables, and we use the renormalization group to resum them. The resummed results that we obtain are more general though less predictive than those proposed by other groups, in that they can accommodate for violations of Sudakov factorization.Comment: 21 pages, no figures. Final version to be published in Nucl. Phys. B. Discussion on colour structure added (eqs.(3.17)-(3.18)

“We face rape. We face all things”: Understandings of gender-based violence amongst female students at a South African university

This study explores how female residence students at a South African university understand and experience gender-based violence. This article examines how women’s identities and social interactions are affected by the presence of gender-based violence in their communities, and specifically the issue of violence in higher education institutions. Social constructionist theory framed this study as it focuses on how these women’s ‘talk’ constructed their understanding of gender-based violence. Unstructured interviews were conducted with 12 female residence students and discourse analysis was used to analyse the interview material. Findings revealed that the fear of becoming a victim of gender-based violence serves to constrict the daily activities of these women. This research maps these ongoing discourses of fear which are present in all aspects of women’s lives. It provides a formal articulation of women’s experiences that are significant but frequently marginalised and normalised, showing the pervasive effects of fear of gender-based violence on identity and social life. The study contributes towards a growing body of knowledge surrounding the impact of gender-based violence at higher education institutions and works towards protecting students.Keywords: Gender-based violence; South Africa; women; students; higher education; fea

The first confirmed superoutburst of the SU UMa type dwarf nova SDSS J083931.35+282824.0

We report unfiltered CCD photometry of the first confirmed superoutburst of the recently discovered dwarf nova, SDSS J083931.35+282824.0 in April 2010. From a quiescence magnitude of ~19.8 it rose to 14.0, an outburst amplitude of at least 5.8 magnitudes. Only the plateau phase of the outburst was observed during which superhumps with peak-to-peak amplitude of up to 0.28 magnitudes were present, confirming this to be an SU UMa type dwarf nova. The mean superhump period was Psh = 0.07836(2) during the first 3 days and this subsequently decreased to 0.07800(3) d. Analysis of the data revealed tentative evidence for an orbital period Porb = 0.07531(25) d. The fractional superhump period excess was epsilon = 0.039(6), which is consistent with other dwarf novae of similar orbital period.Comment: 12 pages, 3 figures. Accepted for publication in the Journal of the British Astronomical Associatio

The Development of Teaching Case Studies to Explore Ethical Issues Associated with Computer Programming

In the past decade software products have become pervasive in many aspects of people’s lives around the world. Unfortunately, the quality of the experience an individual has interacting with that software is dependent on the quality of the software itself, and it is becoming more and more evident that many large software products contain a range of issues and errors, and these issues are not known to the developers of these systems, and they are unaware of the deleterious impacts of those issues on the individuals who use these systems. The authors of this paper are developing a new digital ethics curriculum for the instruction of computer science students. In this paper we present case studies that were explored to demonstrate programming issues to First Year Computer Science students. Each case study outlines key issues associated with a particular scenario and is accompanied by specific questions to be used by the instructor to allow students to begin to reflect on, and evaluate, the implications of these issues. The objective of this teaching content is to ensure that the students are presented with, and engage with, ethical considerations early in their studies and well before they encounter them in an employment setting