We report on the experimental generation of a train of subpicosecond electron bunches. The bunch train generation is accomplished using a beamline capable of exchanging the coordinates between the horizontal and longitudinal degrees of freedom. An initial beam consisting of a set of horizontally-separated beamlets is converted into a train of bunches temporally separated with tunable bunch duration and separation. The experiment reported in this Letter unambiguously demonstrates the conversion process and its versatility.

The experimentally measured rates of the semileptonic decays K {yields} {pi}/{nu} and D {yields} K({pi})/{nu} can be combined with lattice calculations of the associated form factors to precisely extract the CKM matrix elements |V{sub us}| and |V{sub cs(d)}|. We report on the status of form factor calculations with Fermilab charm quarks and staggered light quarks on the 2+1 flavor asqtad staggered MILC ensembles. Analysis of data for the D {yields} {pi}/{nu} form factor provides a nontrivial test of our methods via comparison with CLEO data. We discuss the use of HISQ valence quarks to calculate the K {yields} {pi}/{nu} form factor f{sub +}{sup K{pi}}(0) and describe tests of our method.

Theoretically, the transuranic conversion ratio (CR), i.e. the transuranic production divided by transuranic destruction, in a fast reactor can range from near zero to about 1.9, which is the average neutron yield from Pu239 minus 1. In practice, the possible range will be somewhat less. We have studied the implications of transuranic conversion ratio of 0.0 to 1.7 using the fresh and discharge fuel compositions calculated elsewhere. The corresponding fissile breeding ratio ranges from 0.2 to 1.6. The cases below CR=1 (“burners”) do not have blankets; the cases above CR=1 (“breeders”) have breeding blankets. The burnup was allowed to float while holding the maximum fluence to the cladding constant. We graph the fuel burnup and composition change. As a function of transuranic conversion ratio, we calculate and graph the heat, gamma, and neutron emission of fresh fuel; whether the material is “attractive” for direct weapon use using published criteria; the uranium utilization and rate of consumption of natural uranium; and the long-term radiotoxicity after fuel discharge. For context, other cases and analyses are included, primarily once-through light water reactor (LWR) uranium oxide fuel at 51 MWth-day/kg-iHM burnup (UOX-51). For CR<1, the heat, gamma, and neutron emission increase as material is …

The objective of this note is to (once again) explore the AGS 'ORM' (orbit response matrix) data taken (by Operations) early during the 2007 run with an AGS bare machine and gold beam. Indeed the present motivation is to extract as much information about the AGS inherent transverse coupling as possible - from general arguments and the copious ORM data. And taking this one step further, (though not accomplished yet) the goal really should be to tell the model how to describe this coupling. 'Bare' as used here means the AGS with no quadrupole, sextupole or octupole magnets powered. Only the main (combined-function) magnet string and dipole bumps necessary to optimize beam survival are powered. 'ORM data' means the systematic recording of the equilibrium orbit beam position monitor response to powering individual dipole corrector magnets. The 'matrix' results from looking at the effect of each of the (12 superperiods X 4 dipoles per superperiod) 'kicks' on each of the (12 X 6) pick up electrodes (pues) in each transverse plane. So then we have two (48 X 72) matrices of numbers from the ORM data. (Though 'pue' usually refers to the hardware in the vacuum chamber and 'bpm' to the …

The National Renewable Energy Laboratory's (NREL) Nonpetroleum-Based Fuel Task addresses the hurdles to commercialization of biomass-derived fuels and fuel blends. One such hurdle is the unknown compatibility of new fuels with current infrastructure, such as the equipment used at service stations to dispense fuel into automobiles. The U.S. Department of Energy's (DOE) Vehicle Technology Program and the Biomass Program have engaged in a joint project to evaluate the potential for blending ethanol into gasoline at levels higher than nominal 10 volume percent. This project was established to help DOE and NREL better understand any potentially adverse impacts caused by a lack of knowledge about the compatibility of the dispensing equipment with ethanol blends higher than what the equipment was designed to dispense. This report provides data about the impact of introducing a gasoline with a higher volumetric ethanol content into service station dispensing equipment from a safety and a performance perspective.

We report a preliminary measurement of the CP violating asymmetry in D{sup 0} {yields} {pi}{sup +}{pi}{sup -} using approximately 215,000 decays reconstructed in about 5.94/fb of CDF data. We use the strong D* {+-} D{sup 0}{pi}{sup +} decay (D* tag) to identify the flavor of the charmed meson at production time and exploit CP-conserving strong c-{bar c} pair-production in p-{bar p} collisions. Higher statistic samples of Cabibbo-favored D{sup 0} {yields} K{sup -}{pi}{sup +} decays with and without D* tag are used to highly suppress systematic uncertainties due to detector effects. The result is the world's most precise measurement to date.

This fact sheet describes NREL's accomplishments in fuel cell membrane electrode assembly research and development. Work was performed by the Hydrogen Technologies and Systems Center and the National Center for Photovoltaics.

This fact sheet describes NREL's accomplishments in analyzing life-cycle costs for hydrogen storage in comparison with other energy storage technologies. Work was performed by the Hydrogen Technologies and Systems Center.

This fact sheet describes NREL's accomplishments in fermentative and electrohydrogenic production of hydrogen from corn stover. Work was performed by NREL's Biosciences Center and Pennsylvania State University.

This status report, fourth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory, summarizes progress and accomplishments from demonstrations of fuel cell transit buses in the United States. This year's assessment report provides the results from the fifth year of operation of five Van Hool, ISE, and UTC Power fuel cell buses operating at AC Transit, SunLine, and CTTRANSIT. The achievements and challenges of this bus design, implementation, and operating are presented, with a focus on the next steps for implementing larger numbers and new and different designs of fuel cell buses. The major positive result from nearly five years of operation is the dramatic increase in reliability experienced for the fuel cell power system.

The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

We give a progress report on the calculation of B meson mixing matrix elements, focusing on contributions that could arise beyond the Standard Model. The calculation uses asqtad (light quark) and Fermilab (heavy quark) valence actions and MILC ensembles with 2+1 flavors of asqtad sea quarks. We report preliminary B{sub s}{sup 0} fit results, at a lattice spacing of 0.12 fm, for the SUSY basis of effective four-quark mixing operators and include an estimate for the final error budget.

The Monte Carlo radiation transport code MARS is used to model the generation of gas bremsstrahlung (GB) radiation from 7-GeV electrons which scatter from residual gas atoms in undulator straight sections within the Advanced Photon Source (APS) storage ring. Additionally, MARS is employed to model the interactions of the GB radiation with components along the x-ray beamlines and then determine the expected radiation dose-rates that result. In this manner, MARS can be used to assess the adequacy of existing shielding or the specifications for new shielding when required. The GB radiation generated in the 'thin-target' of an ID straight section will consist only of photons in a 1/E-distribution up to the full energy of the stored electron beam. Using this analytical model, the predicted GB power for a typical APS 15.38-m insertion device (ID) straight section is 4.59 x 10{sup -7} W/nTorr/mA, assuming a background gas composed of air (Z{sub eff} = 7.31) at room temperature (293K). The total GB power provides a useful benchmark for comparisons between analytical and numerical approaches. We find good agreement between MARS and analytical estimates for total GB power. The extended straight section 'target' creates a radial profile of GB, which is highly peaked …

This report examines how the HTGR technology family can provide options for the once through, modified open cycle (MOC), or full recycle fuel cycle strategies. The HTGR can serve all the fuel cycle missions that an LWR can; both are thermal reactors. Additional analyses are warranted to determine if HTGR “full recycle” service could provide improved consumption of transuranic (TRU) material than LWRs (as expected), to analyze the unique proliferation resistance issues associated with the “pebble bed” approach, and to further test and analyze methods to separate TRISO-coated fuel particles from graphite and/or to separate used HTGR fuel meat from its TRISO coating. The feasibility of these two separation issues is not in doubt, but further R&D could clarify and reduce the cost and enable options not adequately explored at present. The analyses here and the now-demonstrated higher fuel burnup tests (after the illustrative designs studied here) should enable future MOC and full recycle HTGR concepts to more rapidly consume TRU, thereby offering waste management advantages. Interest in “limited separation” or “minimum fuel treatment” separation approaches motivates study of impurity-tolerant fuel fabrication.

This document compiles lessons learned and provides a step-by-step process for implementing effective policy assistance.

November 2010 update from the FEMP Federal Fleet Program that outlines vehicle, alternative fuel, infrastructure, and management strategy updates to Federal agencies.

We developed a non-aqueous based electrodepostion process of Ag-stabilization layer on YBCO superconductor tapes. The non-aqueous electroplating solution is non-reactive to the HTS layer thus does not detoriate the critical current capability of the superconductor layer when plated directly on the HTS tape. The superconducting current capabilities of these tapes were measured by non-contact magnetic measurements.

This report summarizes results from an invited two-day colloquium of twenty-nine combustion engine experts from academia, industry, and national labs that was convened March 3rd and 4th, 2010, at the headquarters of the United States Council for Automotive Research (USCAR) in Southfield, Michigan. The colloquium was held at the request of The Department of Energy (DOE) Office of Freedom Car and Vehicle Technologies (OFCVT) to review and assess the current state of transportation combustion engine technology from theoretical and practical perspectives. In the ensuing discussions, the experts were able to reach a broad consensus on some important questions regarding current fuel efficiency limits. They also identified technology barriers and recommended specific near and longer-term R&amp;D priorities for DOE's consideration. Internal combustion engines currently play a dominant role in U.S. transportation and are expected to continue to do so well beyond 2020 [1]. Because of this, the Department of Energy (DOE) has placed high priority on promoting technologies that maximize combustion engine fuel efficiency while minimizing greenhouse gas emissions. Identification of the most promising paths to achieve these goals has recently become more complicated as non-traditional transportation fuels and hybrid electric vehicles become widely available. To reassess the state of combustion …

Automotive and energy researchers have made considerable efforts to predict the impact of plug-in hybrid vehicle (PHEV) charging on the electrical grid. This work has been done primarily through computer modeling and simulation. The US Department of Energy’s (DOE) Advanced Vehicle Testing Activity (AVTA), in partnership with the University of California at Davis’s Institute for Transportation Stuides, have been collecting data from a diverse fleet of PHEVs. The AVTA is conducted by the Idaho National Laboratory for DOE’s Vehicle Technologies Program. This work provides the opportunity to quantify the petroleum displacement potential of early PHEV models, and also observe, rather than simulate, the charging behavior of vehicle users. This paper presents actual charging behavior and the resulting electricity demand from these PHEVs operating in undirected, real-world conditions. Charging patterns are examined for both commercial-use and personal-use vehicles. Underlying reasons for charging behavior in both groups are also presented.

This brochure provides a high-level overview of the U.S. Department of Energy Solar Decathlon 2011. The competition's background, purpose, impact, 10 contests, 20 teams, and where to go for additional information.

This document describes the fuel cell transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA). This document provides a description of the demonstration sites, funding sources, and data collection activities for fuel cell transit bus evaluations currently planned from FY10 through FY12.

This fact sheet describes NREL's accomplishments in analyzing gaps in codes and standards for alternative vehicle fuels, including hydrogen. Work was performed by the Hydrogen Technologies and Systems Center.

The non-intrusive inspection (NII) of consolidated air cargo carried on commercial passenger aircraft continues to be a technically challenging, high-priority requirement of the Department of Homeland Security's Science and Technology Directorate (DHS S&amp;T), the Transportation Security Agency and the Federal Aviation Administration. The goal of deploying a screening system that can reliably and cost-effectively detect explosive threats in consolidated cargo without adversely affecting the flow of commerce will require significant technical advances that will take years to develop. To address this critical National Security need, the Battelle Memorial Institute (Battelle), under a Cooperative Research and Development Agreement (CRADA) with four of its associated US Department of Energy (DOE) National Laboratories (Oak Ridge, Pacific Northwest, Idaho, and Brookhaven), conducted a research and development initiative focused on identifying, evaluating, and integrating technologies for screening consolidated air cargo for the presence of explosive threats. Battelle invested $8.5M of internal research and development funds during fiscal years 2007 through 2009. The primary results of this effort are described in this document and can be summarized as follows: (1) Completed a gap analysis that identified threat signatures and observables, candidate technologies for detection, their current state of development, and provided recommendations for improvements to meet …

The fact sheet summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.