18 research outputs found

    Astrophysical Origins of Ultrahigh Energy Cosmic Rays

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    In the first part of this review we discuss the basic observational features at the end of the cosmic ray energy spectrum. We also present there the main characteristics of each of the experiments involved in the detection of these particles. We then briefly discuss the status of the chemical composition and the distribution of arrival directions of cosmic rays. After that, we examine the energy losses during propagation, introducing the Greisen-Zaptsepin-Kuzmin (GZK) cutoff, and discuss the level of confidence with which each experiment have detected particles beyond the GZK energy limit. In the second part of the review, we discuss astrophysical environments able to accelerate particles up to such high energies, including active galactic nuclei, large scale galactic wind termination shocks, relativistic jets and hot-spots of Fanaroff-Riley radiogalaxies, pulsars, magnetars, quasar remnants, starbursts, colliding galaxies, and gamma ray burst fireballs. In the third part of the review we provide a brief summary of scenarios which try to explain the super-GZK events with the help of new physics beyond the standard model. In the last section, we give an overview on neutrino telescopes and existing limits on the energy spectrum and discuss some of the prospects for a new (multi-particle) astronomy. Finally, we outline how extraterrestrial neutrino fluxes can be used to probe new physics beyond the electroweak scale.Comment: Higher resolution version of Fig. 7 is available at http://www.angelfire.com/id/dtorres/down3.html. Solicited review article prepared for Reports on Progress in Physics, final versio

    Co-productive agility and four collaborative pathways to sustainability transformations

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    Co-production, the collaborative weaving of research and practice by diverse societal actors, is argued to play an important role in sustainability transformations. Yet, there is still poor understanding of how to navigate the tensions that emerge in these processes. Through analyzing 32 initiatives worldwide that co-produced knowledge and action to foster sustainable social-ecological relations, we conceptualize ‘co-productive agility’ as an emergent feature vital for turning tensions into transformations. Co-productive agility refers to the willingness and ability of diverse actors to iteratively engage in reflexive dialogues to grow shared ideas and actions that would not have been possible from the outset. It relies on embedding knowledge production within processes of change to constantly recognize, reposition, and navigate tensions and opportunities. Co-productive agility opens up multiple pathways to transformation through: (1) elevating marginalized agendas in ways that maintain their integrity and broaden struggles for justice; (2) questioning dominant agendas by engaging with power in ways that challenge assumptions, (3) navigating conflicting agendas to actively transform interlinked paradigms, practices, and structures; (4) exploring diverse agendas to foster learning and mutual respect for a plurality of perspectives. We explore six process considerations that vary by these four pathways and provide a framework to enable agility in sustainability transformations. We argue that research and practice spend too much time closing down debate over different agendas for change – thereby avoiding, suppressing, or polarizing tensions, and call for more efforts to facilitate better interactions among different agendas

    Co-productive agility and four collaborative pathways to sustainability transformations

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    Co-production, the collaborative weaving of research and practice by diverse societal actors, is argued to play an important role in sustainability transformations. Yet, there is still poor understanding of how to navigate the tensions that emerge in these processes. Through analyzing 32 initiatives worldwide that co-produced knowledge and action to foster sustainable social-ecological relations, we conceptualize ‘co-productive agility’ as an emergent feature vital for turning tensions into transformations. Co-productive agility refers to the willingness and ability of diverse actors to iteratively engage in reflexive dialogues to grow shared ideas and actions that would not have been possible from the outset. It relies on embedding knowledge production within processes of change to constantly recognize, reposition, and navigate tensions and opportunities. Co-productive agility opens up multiple pathways to transformation through: (1) elevating marginalized agendas in ways that maintain their integrity and broaden struggles for justice; (2) questioning dominant agendas by engaging with power in ways that challenge assumptions, (3) navigating conflicting agendas to actively transform interlinked paradigms, practices, and structures; (4) exploring diverse agendas to foster learning and mutual respect for a plurality of perspectives. We explore six process considerations that vary by these four pathways and provide a framework to enable agility in sustainability transformations. We argue that research and practice spend too much time closing down debate over different agendas for change – thereby avoiding, suppressing, or polarizing tensions, and call for more efforts to facilitate better interactions among different agendas

    The certainty of uncertainty in marine conservation and what to do about it

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    The confounding effects of difficult sampling and dynamic systems make uncertainty the norm for managers of marine ecosystems. Thus managers need approaches that use relatively small amounts of information and account for a wide suite of biological and physical influences. Here we use a case study approach to review the use of several possible techniques for making decisions about marine ecosystems despite uncertainty. We describe the use of expert judgment in the rebuilding plans for data-poor us fisheries, models to manage the krill fishery in the Southern Ocean to account for both the impacts of climate change and the resource needs of krill predators, an integrated risk assessment framework to prioritize shark management in the Atlantic Ocean despite severe data limitations, and models to account for climate impacts on salmonid populations in California. Through this review, we show that with limited information, managers can use models to explore how highly variable systems might respond to management options under different scenarios. Expert judgment can help shape the assumptions that form the basis for those models and propose sensible boundaries within which management options can be developed. A weight of evidence approach can take advantage of small amounts of information from multiple sources, including models and expert judgment. Although none of these approaches is perfect, they can help provide a logical starting point for conservation and management, despite the certainty of uncertainty

    Ohio History 2015

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    https://kent-islandora.s3.us-east-2.amazonaws.com/node/10127/OH-v122-thumb.jpgOHIO HISTORY Contents for Volume 122, 2015 Contested Patriarchy: John Cleves Symmes and the Struggle for Family Control in the Post-revolutionary West Cathy Rodabaugh ...... 5 Ralph Keeler: A Delightful Arabesque of Invention and Sentiment Larry Lee Nelson ...... 29 Peace Be with You: Leftist Activism at John Carroll University, 1967–69 Michael Daniel Goodnough ...... 49 Water in the Shaping of Columbus, Ohio, 1812–1912 Mansel G. Blackford ......&nbsp; 65 &nbsp; Book Reviews ...... 89 &nbsp; On the cover: The Columbus water-treatment plant was one of the most modern in the world, and worked well in all weather. (Columbus Metropolitan Library)</p

    A research agenda for the science of actionable knowledge: Drawing from a review of the most misguided to the most enlightened claims in the science-policy interface literature

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    Linking science with action affords a prime opportunity to leverage greater societal impact from research and increase the use of evidence in decision-making. Success in these areas depends critically upon processes of producing and mobilizing knowledge, as well as supporting and making decisions. For decades, scholars have idealized and described these social processes in different ways, resulting in numerous assumptions that now variously guide engagements at the interface of science and society. We systematically catalog these assumptions based on prior research on the science-policy interface, and further distill them into a set of 26 claims. We then elicit expert perspectives (n = 16) about these claims to assess the extent to which they are accurate or merit further examination. Out of this process, we construct a research agenda to motivate future scientific research on actionable knowledge, prioritizing areas that experts identified as critical gaps in understanding of the science-society interface. The resulting agenda focuses on how to define success, support intermediaries, build trust, and evaluate the importance of consensus and its alternatives – all in the diverse contexts of science-society-decision-making interactions. We further raise questions about the centrality of knowledge in these interactions, discussing how a governance lens might be generative of efforts to support more equitable processes and outcomes. We offer these suggestions with hopes of furthering the science of actionable knowledge as a transdisciplinary area of inquiry
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