Beam Loss Control for the Fermilab Main Injector

From 2005 through 2012, the Fermilab Main Injector provided intense beams of 120 GeV protons to produce neutrino beams and antiprotons. Hardware improvements in conjunction with improved diagnostics allowed the system to reach sustained operation at 400 kW beam power. Losses were at or near the 8 GeV injection energy where 95% beam transmission results in about 1.5 kW of beam loss. By minimizing and localizing loss, residual radiation levels fell while beam power was doubled. Lost beam was directed to either the collimation system or to the beam abort. Critical apertures were increased while improved instrumentation allowed optimal use of available apertures. We will summarize the impact of various loss control tools and the status and trends in residual radiation in the Main Injector.Comment: 5 p

A process-oriented language for describing aspects of reading comprehension

Includes bibliographical references (p. 36-38)The research described herein was supported in part by the National Institute of Education under Contract No. MS-NIE-C-400-76-011

Locating Local Education Funds: A Conceptual Framework for Describing LEFs' Contribution to Public Education

With support and leadership from the Public Education Network (PEN), local education funds (LEFs) have worked for two decades to 1) educate and mobilize their communities so that citizen voices are influential in education policy discussions; and 2) support effective partnerships between school district insiders and outsiders to improve the quality of children's education. However, as Useem's study of local education funds points out, it has been difficult to identify the many roles that LEFs play in their communities, the work that they undertake, the obstacles that they encounter, and the contributions that they make. Useem also suggests why the work of LEFs defies simple description. As brokers, LEFs work behind the scenes and in partnership with others, which contributes to their invisibility as catalysts and supporters of educational improvement. LEFs also are highly adaptive organizations that typically customize their change strategies to particular communities. Such attention to local context results in tremendous variation in the organization, work, and accomplishments of LEFs. At the same time, the highly individual nature of each LEF often obscures the overarching values, purposes, and goals that these organizations share, thus obscuring a collective identity.As they mark 20 years of work in public education, LEF and PEN leaders are prescient in their insistence on further research into the role and accomplishments of local education funds in shaping the landscape of public schooling. In August 2003, at the request of PEN, Research for Action (RFA) began work on developing a conceptual framework for: 1) understanding the role and work of LEFs and the many factors that influence what they do and how they do it; and 2) assessing their contributions to public education.This framework will be used to guide future empirical research on LEFs and to develop tools that LEFs themselves can use in a process of self-assessment. Continued research and assessment will provide public education stakeholders with credible evidence and a deeper understanding about how LEFs carry out their missions and demonstrate successes. At the same time, it will provide firm ground for LEF and PEN leaders to chart the next generation of work. This report was prepared for Public Education Network by Research for Action

On the expected uniform error of geometric Brownian motion approximated by the L\'evy-Ciesielski construction

It is known that the Brownian bridge or L\'evy-Ciesielski construction of Brownian paths almost surely converges uniformly to the true Brownian path. In the present article the focus is on the error. In particular, we show for geometric Brownian motion that at level $N$, at which there are $d=2^N$ points evaluated on the Brownian path, the expected uniform error has an upper bound of order $\mathcal{O}(\sqrt{N/2^N})$, or equivalently, $\mathcal{O}(\sqrt{\ln d/d})$. This upper bound matches the known order for the expected uniform error of the standard Brownian motion. We apply the result to an option pricing example

No. 06: The Urban Food System of Nairobi, Kenya

Nairobi is a city of stark contrasts. Nearly half a million of its three million residents live in abject poverty in some of Africa’s largest slums, yet the Kenyan capital is also an international and regional hub. In East Africa, rapid urbanization is stretching existing food and agriculture systems as growing cities struggle to provide food and nutrition security for their inhabitants. Nairobi is no exception; it is a dynamically growing city and its food supply chains are constantly adapting and responding to changing local conditions. It is also an international city and the extent to which it is food secure is increasingly predicated on food imports from the regional East African Community and other international sources. Informal traditional value chains have a variety of actors and intermediaries that increase transaction costs and create an inefficient post-harvest procurement network, thereby pushing food products out of the reach of those who need them most. The majority of Nairobi’s food purchases are from informal food vendors. The city’s urban poor rely on the informal food sector for several reasons including that it provides food close to where they live and work, credit and barter are often available, small quantities can be purchased, and many items are sold more cheaply than at formal outlets. The leading income-generating activity for women in Nairobi’s poor communities is selling fruit and vegetables

FINDCHIRP: an algorithm for detection of gravitational waves from inspiraling compact binaries

Matched-filter searches for gravitational waves from coalescing compact binaries by the LIGO Scientific Collaboration use the FINDCHIRP algorithm: an implementation of the optimal filter with innovations to account for unknown signal parameters and to improve performance on detector data that has nonstationary and non-Gaussian artifacts. We provide details on the FINDCHIRP algorithm as used in the search for subsolar mass binaries, binary neutron stars, neutron star-black hole binaries, and binary black holes.Comment: 19 pages, 1 figure, journal version with Creative Commons 4.0 open-access license adde