The High-Metallicity Explosion Environment of the Relativistic Supernova 2009bb

We investigate the environment of the nearby (d ~ 40Mpc) broad-lined Type Ic supernova SN 2009bb. This event was observed to produce a relativistic outflow likely powered by a central accreting compact object. While such a phenomenon was previously observed only in long-duration gamma-ray bursts (LGRBs), no LGRB was detected in association with SN 2009bb. Using an optical spectrum of the SN 2009bb explosion site, we determine a variety of ISM properties for the host environment, including metallicity, young stellar population age, and star formation rate. We compare the SN explosion site properties to observations of LGRB and broad-lined SN Ic host environments on optical emission line ratio diagnostic diagrams. Based on these analyses, we find that the SN 2009bb explosion site has a very high metallicity of ~2x solar, in agreement with other broad-lined SN Ic host environments and at odds with the low-redshift LGRB host environments and recently proposed maximum metallicity limits for relativistic explosions. We consider the implications of these findings and the impact that SN 2009bb's unusual explosive properties and environment have on our understanding of the key physical ingredient that enables some SNe to produce a relativistic outflow.Comment: 7 pages, 4 figures, 1 table; accepted for publication in ApJ Letters (replaced to include missing figure

Design and Poverty : A Review of Contexts, Roles of Poor People, and Methods

Design is essential to fulfil unmet or under-served needs of resource-poor societies, supporting their social and human development. A great deal of design research has been undertaken in such low resource settings, and is discussed under different names, such as ‘community development engineering’, ‘humanitarian engineering’, ‘appropriate technology’, ‘design for development’, ‘design at the Base of the Pyramid’, etc. This has created an important need to know what has been examined and learnt so far and to plan for further investigation. To address this, we review a broad range of literature, with close examination of 30 design studies in this field. This reveals a multifaceted picture, showing a great diversity in investigation and reporting of attributes of context (income, rural and urban, design sectors, countries, and gender), the roles of poor people (consumers, producers, and co-designers), characteristics of research methods employed (e.g. descriptive and prescriptive, data collection methods, qualitative and quantitative aspects, and unit of analysis), and design topics. Based on the review results, we offer recommendations for further research, identifying concerns that researchers ought to have about this field and suggesting ways in which research in this field can be undertaken and reported