The Mini Astrophysical MeV Background Observatory (MAMBO) CubeSat Mission

The origin of the cosmic diffuse gamma-ray (CDG) background in the 0.3 – 30 MeV energy range is a mystery that has persisted for over 40 years. The Mini Astrophysical MeV Background Observatory (MAMBO) is a CubeSat mission concept motivated by the fact that, since the MeV CDG is relatively bright, only a small detector is required to make high-quality measurements of it. Indeed, the sensitivity of space-based gamma-ray instruments to the CDG is limited not by size, but by the locally generated instrumental background produced by interactions of energetic particles in spacecraft materials. Comparatively tiny CubeSat platforms provide a uniquely quiet environment relative to previous gamma-ray science missions. The MAMBO mission will provide the best measurements ever made of the MeV CDG spectrum and angular distribution, utilizing two key innovations: 1) low instrumental background on a 12U CubeSat platform; and 2) an innovative shielded spectrometer design that simultaneously measures signal and background. Enabling technologies include the use of compact silicon photomultipliers (SiPMs) for scintillator readout, and a tagged calibration source for real-time gain adjustment. We describe the MAMBO instrument, readout, commercial 12U bus systems, and mission concept in detail, including simulations and laboratory measurements demonstrating the key measurement concept

Improved Gamma Bang Time Measurements on Omega and Implications for the National Ignition Facility

The time of peak fusion reactivity with respect to the impingement of laser light on an ICF capsule is known as Bang Time (BT). This is an essential parameter in the understanding of ICF implosions. Traditionally, BT has been determined through temporal measurements of 14 MeV fusion neutrons. Because the neutron energy spectrum is Doppler broadened, the detector must be positioned close to target-chamber center in order to minimize the neutron temporal spreading which can compromise such a measurement. Fusion gammas, on the other hand, are not subject to temporal spreading, making proximity of the detector to the source a lesser concern. However, the low branching ratio for DT fusion reactions producing gammas ({approx}1e-4) presents detector sensitivity challenges

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Teaching the Newly Essential Knowledge, Skills, and Values in a Changing World, Section E: Intercultural Effectiveness

As of 2015, legal education has experienced five successive years of intense challenges: enrollments reduced by half of their highest level, pressure to prepare students for a legal services market undergoing major restructuring, significant new bar admission and accreditation requirements. Building on Best Practices: Transforming Legal Education in a Changing World (Lexis 2015) provides a wealth of guidance for institutions and individual teachers facing these challenges. Organized into eight chapters divided into 33 sections, the book draws on the wisdom of 57 authors, including three deans or former deans. The volume suggests best practices, or emerging best practices, for many aspects of legal education. Law school faculty and administrators can find thoughtful advice, whether they are working on school-wide curricular reform or teaching methods within one class. The book provides suggestions for different types of courses, classes and teaching methods, including the socratic method, teaching technologies, and experiential courses, especially those involving real legal work. The book also addresses newly essential areas of knowledge, skills and values, including professional identity formation, intercultural effectiveness, and business and financial literacy.https://digitalrepository.unm.edu/law_facbookdisplay/1096/thumbnail.jp

SRF Cavity High-Gradient Study at 805 MHz for Proton and Other Applications

805 MHz elliptical SRF cavities have been used for SNS as the first application for protons. At LANL, an R&D started to explore a capability of getting high-gradient cavities (40-50 MV/m) at this frequency for the future applications such as proton and muon based interrogation testing facility added to the LANSCE accelerator and a power upgrade of the LANSCE accelerator for the fission and fusion material test station. Optimized cell designs for “standard”, “low-loss” and “re-entrant” shapes, cavity test results for “standard” single-cell cavities with temperature mapping as well as surface inspection results will be presented

In situ calibration of the Gamma Reaction History instrument using reference samples (“pucks”) for areal density measurements

The introduction of a sample of carbon, for example a disk or “puck”, near an imploding DT-filled capsule creates a source of 12C gamma rays that can serve as a reference for calibrating the response of the Gamma Reaction History (GRH) detector [1]. Such calibration is important in the measurement of ablator areal density ⟨ρR⟩abl in plastic-ablator DT-filled capsules at OMEGA [2], by allowing ⟨ρR⟩abl to be inferred as a function of ratios of signals rather than from absolute measurements of signal magnitudes. Systematic uncertainties in signal measurements and detector responses therefore cancel, permitting more accurate measurements of ⟨ρR⟩abl

calibration of the Gamma Reaction History instrument using reference samples (“pucks”) for areal density measurements

The introduction of a sample of carbon, for example a disk or “puck”, near an imploding DT-filled capsule creates a source of 12C gamma rays that can serve as a reference for calibrating the response of the Gamma Reaction History (GRH) detector [1]. Such calibration is important in the measurement of ablator areal density ⟨ρR⟩abl in plastic-ablator DT-filled capsules at OMEGA [2], by allowing ⟨ρR⟩abl to be inferred as a function of ratios of signals rather than from absolute measurements of signal magnitudes. Systematic uncertainties in signal measurements and detector responses therefore cancel, permitting more accurate measurements of ⟨ρR⟩abl

Advancing Human Rights Policy: Does Grassroots Mobilization and Community Dispute Resolution Matter? Insights from Chiapas, Mexico

This research examines the impact of grassroots organizing at the community level in Chiapas, Mexico, to address problems associated with human rights advocacy and implementation. Traditionally, the nation-state has had the primary responsibility to address issues pertaining to human rights violations and the enforcement of international human rights principles and treaties. Local political struggles and acts of resistance by disenfranchised groups in Mexico offer insight to understand the impact of indigenous and other social movements in furthering human rights. Indigenous populations in the state of Chiapas use local community dispute resolution to contest the inadequacy of the state in responding to the problems that give rise to poverty, lack of human dignity, educational access, racial and ethnic discrimination, lack of political participation in government and the right to equality in economic, social, and political sectors. Drawing from research based on participant observations in Chiapas, Mexico, there is some evidence to suggest that since the 1994 EZLN (Zapatista National Liberation Army) uprising several micro-level political and social movements have contested the power of the state through symbolic and pragmatic organizing efforts. These groups include, but are not limited to, nongovernmental organizations (NGOs), women's groups, and indigenous groups. After the Zapatista uprising, these groups were instrumental in making claims against the state through numerous activities: protests to end the war, the development of NGOs to observe human rights violations, civilian-based Zapatista support groups (base de apoyo), peace camps, and open dialogue with the EZLN. I argue that collective mobilization in local communities serves both symbolic and pragmatic efforts in helping disenfranchised groups empower themselves to address economic, social, and political inequality. Local-level activism has fueled a sense of self-empowerment to change state institutional responses and to involve sectors of civil society domestically and internationally to initiate a proper resolution of issues that are fundamentally related to human rights. Copyright 2005 by The Policy Studies Organization.