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This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the 2011 U.S. Department of Energy Biomass Program’s Peer Review meeting.
Many of the interesting physics processes to be measured at the LHC have a signature involving one or more isolated electrons. The electron reconstruction and identification efficiencies of the ATLAS detector at the LHC have been evaluated using proton–proton collision data collected in 2011 at √s = 7 TeV and corresponding to an integrated luminosity of 4.7 fb -1 . Tag-and-probe methods using events with leptonic decays of W and Z bosons and J/ψ mesons are employed to benchmark these performance parameters. The combination of all measurements results in identification efficiencies determined with an accuracy at the few per mil level for electron transverse energy greater than 30 GeV.
This proposal supported Chemistry Symposia at the 2011 American Association for the Advancement of Science (AAAS) Meeting in Washington, DC February 17-21, 2011. The Chemistry Section of AAAS presented an unusually strong set of symposia for the 2011 AAAS meeting to help celebrate the 2011 International Year of Chemistry. The AAAS meeting provided an unusual opportunity to convey the excitement and importance of chemistry to a very broad audience and allowed access to a large contingent of the scientific press. Excellent suggestions for symposia were received from AAAS Chemistry Fellows and from the chairs of the American Chemical Society Technical Divisions. The AAAS Chemistry executive committee selected topics that would have wide appeal to scientists, the public, and the press for formal proposals of symposia. The symposia proposals were peer reviewed by AAAS. The Chemistry Section made a strong case to the program selection committee for approval of the chemistry symposia and 6 were approved for the 2011 annual meeting. The titles of the approved symposia were: (1) Powering the Planet: Generation of Clean Fuels from Sunlight and Water, (2) Biological Role and Consequences of Intrinsic Protein Disorder, (3) Chemically Speaking: How Organisms Talk to Each Other, (4) Molecular Self-Assembly and Artificial Molecular Machines, (5) Frontiers in Organic Materials for Information Processing, Energy and Sensors, and (6) Celebrating Marie Curie's 100th Anniversary of Her Nobel Prize in Chemistry. The Chemistry Section of AAAS is provided with funds to support only 1-2 symposia a year. Because of the much greater number of symposia approved in conjunction with observance of the 2011 International Year of Chemistry, additional support was sought from DOE to help support the 30 invited speakers and 8 symposia moderators/organizers. Support for the symposia provided the opportunity to highlight the excitement of current chemical research, to educate the public about the achievements of chemistry and its contributions to the well-being of humankind. The 2011 AAAS Annual Meeting provided an important opportunity to play a prominent role in the global celebration of the 2011 International Year of Chemistry.
The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided proton–proton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon–nucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction.
This report documents the analysis of the occurrences during the period January 1, 2011 through December 31, 2011. The report compares LLNL occurrences by reporting criteria and significance category to see if LLNL is reporting occurrences along similar percentages as other DOE sites. The three-year trends are analyzed. It does not include the analysis of the causes or the lessons learned from the occurrences, as they are analyzed separately. The number and types of occurrences that LLNL reports to DOE varies over time. This variation can be attributed to normally occurring changes in frequency; DOE's or LLNL's heightened interest in a particular subject area; changes in LLNL processes; or emerging problems. Since all of the DOE sites use the same reporting criteria, it is helpful to understand if LLNL is consistent with or diverging from reporting at other sites. This section compares the normalized number of occurrences reported by LLNL and other DOE sites. In order to compare LLNL occurrence reports to occurrence reports from other DOE sites, we normalized (or standardized) the data from the sites. DOE sites vary widely in their budgets, populations, and scope of work and these variations may affect reporting frequency. In addition, reports are required for a wide range of occurrence types, some of which may not be applicable to all DOE sites. For example, one occurrence reporting group is Group 3, Nuclear Safety Basis, and not all sites have nuclear operations. Because limited information is available for all sites, the sites were normalized based on best available information. Site effort hours were extracted from the DOE Computerized Accident Incident Reporting System (CAIRS) and used to normalize (or standardize) the number of occurrences by site. Effort hours are those hours that employees normally work and do not include vacation, holiday hours etc. Sites are responsible for calculating their effort hours and ensuring entry into CAIRS. Out of the 30 DOE sites that reported occurrences into ORPS during January 2011 through December 2011, 28 had effort hours available in CAIRS. Two sites had not submitted effort hours data to CAIRS as of the time data was pulled for this report. In those two cases, third quarter data was used as an estimate of fourth quarter data. The use of estimated data may introduce minor errors in the average, median, and Pearson calculations. Using the effort hours and the frequency of occurrences by site, a rate of occurrence frequency per 100 FTE workers was calculated. This rate is similar to the injury/illness frequency rate: the number of injury/illness cases per 100 FTE workers. To validate that this rate was appropriate to use, we compared the effort hours and the frequency of occurrences by site to determine if a relationship exists between the two, e.g. the more effort hours a site has, the more occurrences they tend to have. This hypothesis was tested using the Pearson Correlation Coefficient Test. The correlation coefficient measures the strength of the linear relationship between effort hours and occurrence frequency. The Pearson Correlation Coefficient Test will determine if the true correlation coefficient is equal to zero (no relationship exists), or if the correlation coefficient is not equal to zero (a relationship exists). Values approaching 1.00 show a more positive correlation. Simple linear regression was also used to display a trend line and to test if a one-way relationship exists between effort hours predicting the number of occurrences a site will have. Using the Pearson Correlation test, for the NNSA sites, effort hours and the number of occurrences are significantly and positively correlated with a correlation coefficient of 0.90, as was also seen in the previous report (correlation coefficient of 0.67). All DOE sites are positively correlated with a coefficient of 0.85. As the effort hours increase, so does the number of occurrences and vice versa. Based on the results of the simple linear regression, effort hours were found to predict the number of occurrences.
Online-coupled climate and chemistry models are necessary to realistically represent the interactions between climate variables and chemical species and accurately simulate aerosol direct and indirect effects on cloud, precipitation, and radiation. In this Part I of a two-part paper, simulations from the Weather Research and Forecasting model coupled with the physics package of Community Atmosphere Model (WRF-CAM5) are conducted with the default heterogeneous ice nucleation parameterization over East Asia for two full years: 2006 and 2011. A comprehensive model evaluation is performed using satellite and surface observations. The model shows an overall acceptable performance for major meteorological variables at the surface and in the boundary layer, as well as column variables (e.g., precipitation, cloud fraction, precipitating water vapor, downward longwave and shortwave radiation). Moderate to large biases exist for cloud condensation nuclei over oceanic areas, cloud variables (e.g., cloud droplet number concentration, cloud liquid and ice water paths, cloud optical depth, longwave and shortwave cloud forcing). These biases indicate a need to improve the model treatments for cloud processes, especially cloud droplets and ice nucleation, as well as to reduce uncertainty in the satellite retrievals. The model simulates well the column abundances of chemical species except for column SO 2 but relatively poor for surface concentrations of several species such as CO, NO 2 , SO 2 , PM2.5, and PM10. Several reasons could contribute to the underestimation of major chemical species in East Asia including underestimations of anthropogenic emissions and natural dust emissions, uncertainties in the spatial and vertical distributions of the anthropogenic emissions, as well as biases in meteorological, radiative, and cloud predictions. Despite moderate to large biases in the chemical predictions, the model performance is generally consistent with or even better than that reported for East Asia with only a few exceptions. The model generally reproduces the observed seasonal variations and the difference between 2006 and 2011 for most variables or chemical species. Overall, these results demonstrate promising skills of WRF-CAM5 for long-term simulations at a regional scale and suggest several areas of potential improvements.
In fiscal year 2011, the Community Earth System Model (CESM) tutorial was taught at NCAR from 1-5 August 2011. This project hosted 79 full participants (1 accepted participant from China couldn't get a visa) selected from 180 applications. The tutorial was advertised through emails to CESM mailing lists. NCAR staff and long-term visitors (who were not eligible to attend) were also invited to 'audit' the climate and practical lectures and to work on the practical sessions on their own. 15 NCAR staff and long-term visitors took advantage of this opportunity. The majority of the students were graduate students, but several post-docs, faculty, and other research scientists also attended. Additionally, many people are using the on-line lessons and practical sessions. As of August 18, 2011, 407 people had registered to access and use the tutorial from 33 countries all over the world, but a majority from US universities. In fiscal year 2011, the Climate and Global Dynamics Division Information Systems Group (CGD/ISG) built and operated a temporary computer laboratory in a meeting room. This project was made possible through funding from the National Science Foundation Directorate of Geosciences, and the Department of Energy Office of Science.
Guide to the student-designed houses, ten contests, exhibits, and workshops of the U.S. Department of Energy 2011 Solar Decathlon, held in Washington, D.C., from September 23 through October 2, 2011. Teams of college students designed and built the solar-powered houses on display here. They represent 13 U.S. states, five countries, and four continents. Now the teams are rising to the challenge by competing in 10 contests over nine days, with the championship trophy on the line. This is their time to shine. The 2011 teams may share a common goal - to design and build the best energy-efficient house powered by the sun - but their strategies are different. One house is made of precast concrete, while another 'dances' in response to its environment. Another house is meant to sit atop a building, proving the sky's the limit for energy innovation. Whatever your idea of sustainable living may be, you are bound to find it at the Solar Decathlon.
The 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems took place in Austin, Texas (7–11 September 2011). This meeting was organized jointly with the 5th IAEA Technical Meeting on Theory of Plasma Instabilities (5–7 September 2011). The two meetings shared one day (7 September 2011) with presentations relevant to both groups. Some of the work reported at these meetings was then published in a special issue of Nuclear Fusion [Nucl. Fusion 52 (2012)]. Summaries of the Energetic Particle Conference presentations were given by Kazuo Toi and Boris Breizman. They respectively discussed the experimental and theoretical progress presented at the meeting. Highlights of this meeting include the tremendous progress that has been achieved in the development of diagnostics that enables the ‘viewing’ of internal fluctuations and allows comparison with theoretical predictions, as demonstrated, for example, in the talks of P. Lauber and M. Osakabe. The need and development of hardened diagnostics in the severe radiation environment, such as those that will exist in ITER, was discussed in the talks of V. Kiptily and V.A. Kazakhov. In theoretical studies, much of the effort is focused on nonlinear phenomena. For example, detailed comparison of theory and experiment on D-III-D on the n = 0 geodesic mode was reported in separate papers by R. Nazikian and G. Fu. A large number of theoretical papers were presented on wave chirping including a paper by B.N. Breizman, which notes that wave chirping from a single frequency may emanate continuously once marginal stability conditions have been established. Another area of wide interest was the detailed study of alpha orbits in a burning plasma, where losses can come from symmetry breaking due to finite coil number or magnetic field imperfections introduced by diagnostic or test modules. An important area of development, covered by M.A. Hole and D.A. Spong, is concerned with the self-consistent treatment of the induced fields that accounts for toroidally asymmetric MHD response. In addition, a significant number of studies focused on understanding nonlinear behavior by means of computer simulation of energetic particle driven instability. An under-represented area of investigation was the study of electron runaway formation during major tokamak disruptions. It was noted in an overview by S. Putvinski that electron energies in the 10–20 MeV range is to be expected during projected major disruptions in ITER and that reliable methods for mitigation of the runaway process needs to be developed. Significant recent work in the field of the disruption induced electron runaway, which was reported by J. Riemann, had been submitted to Physics of Plasmas. Overall it is clear that reliable mitigation of electron runaway is an extremely important topic that is in need of better understanding and solutions.
The Large Area Telescope on board the Fermi satellite observed a gamma-ray flare in the Crab Nebula lasting for approximately nine days in April of 2011. The source, which at optical wavelengths has a size of Almost-Equal-To 11 lt-yr across, doubled its gamma-ray flux within eight hours. The peak photon flux was (186 {+-} 6) Multiplication-Sign 10{sup -7} cm{sup -2} s{sup -1} above 100 MeV, which corresponds to a 30-fold increase compared to the average value. During the flare, a new component emerged in the spectral energy distribution, which peaked at an energy of (375 {+-} 26) MeV at flare maximum. The observations imply that the emission region was likely relativistically beamed toward us and that variations in its motion are responsible for the observed spectral variability.
We present results from our analysis of Chandra X-Ray Observatory, W. M. Keck Observatory, and Karl G. Jansky Very Large Array (VLA) images of the Crab Nebula that were contemporaneous with the {gamma}-ray flare of 2011 April. Despite hints in the X-ray data, we find no evidence for statistically significant variations that pinpoint the specific location of the flares within the Nebula. The Keck observations extend this conclusion to the 'inner knot', i.e., the feature within an arcsecond of the pulsar. The VLA observations support this conclusion. We also discuss theoretical implications of the {gamma}-ray flares and suggest that the most dramatic {gamma}-ray flares are due to radiation-reaction-limited synchrotron emission associated with sudden, dissipative changes in the current system sustained by the central pulsar.
This study presents the performance of the ATLAS muon reconstruction during the LHC run with pp collisions at √s = 7–8 TeV in 2011–2012, focusing mainly on data collected in 2012. Measurements of the reconstruction efficiency and of the momentum scale and resolution, based on large reference samples of J/ψ → μμ, Z → μμ and Υ → μμ decays, are presented and compared to Monte Carlo simulations. Corrections to the simulation, to be used in physics analysis, are provided. Over most of the covered phase space (muon |η| < 2.7 and 5 ≲ p T ≲ 100 GeV) the efficiency is above 99% and is measured with per-mille precision. The momentum resolution ranges from 1.7% at central rapidity and for transverse momentum p T ≃ 10 GeV, to 4% at large rapidity and p T ≃ 100 GeV. The momentum scale is known with an uncertainty of 0.05% to 0.2% depending on rapidity. A method for the recovery of final state radiation from the muons is also presented.
This report provides an overview of the U.S. Department of Energy Building America program's Summer 2011 Residential Energy Efficiency Technical Update Meeting. This meeting was held on August 9-11, 2011, in Denver, Colorado, and brought together more than 290 professionals representing organizations with a vested interest in energy efficiency improvements in residential buildings.
This report serves as the combined annual report for post-closure activities for the following closed Corrective Action Units (CAUs): • CAU 90, Area 2 Bitcutter Containment; • CAU 91, Area 3 U-3fi Injection Well; • CAU 92, Area 6 Decon Pond Facility; • CAU 110, Area 3 WMD U-3ax/bl Crater; and • CAU 112, Area 23 Hazardous Waste Trenches. This report covers fiscal year 2011 (October 2010-September 2011). The post-closure requirements for these sites are described in Resource Conservation and Recovery Act Permit Number NEV HW0101 and summarized in each CAU-specific section in Section 1.0 of this report. Site inspections are conducted semiannually at CAUs 90 and 91 and quarterly at CAUs 92, 110, and 112. Additional inspections are conducted at CAU 92 if precipitation occurs in excess of 0.50 inches in a 24-hour period. Inspections include an evaluation of the condition of the units and identification of any deficiencies that may compromise the integrity of the units. The condition of covers, fencing, signs, gates, and locks is documented. In addition, soil moisture monitoring and subsidence surveys are conducted at CAU 110. The results of the inspections, summary of maintenance activities, results of vegetations surveys, and analysis of monitoring data are presented in this report. Copies of the inspection checklists are included as Appendix A. Field notes completed during each inspection are included in Appendix B. Photographs taken during the inspections are included in Appendix C. It is recommended to continue semiannual inspections at CAUs 90 and 91; quarterly inspections at CAUs 92, 110, and 112; and additional inspections at CAU 92 if precipitation occurs in excess of 0.50 inches in a 24-hour period. At CAU 92, it is recommended to remove the wave barriers, as they have not proven to be necessary to protect the cover. At CAU 110, it is recommended to continue annual vegetation monitoring and soil moisture monitoring, and to reduce the frequency of subsidence surveys from twice per year to once every other year (biennially).
This report is submitted by the U.S. Department of Energy (DOE) Carlsbad Field Office and Washington TRU Solutions LLC (the Permittees) in accordance with Permit Part 4, Permit Conditions 4.6.2.2 and 4.6.5.2 of the Waste Isolation Pilot Plant (WIPP) Hazardous Waste Facility, Permit Number NM4890139088-TSDF (Permit). This report documents the Volatile Organic Compound (VOC) Monitoring Program and Hydrogen and Methane Monitoring Program results for the 6-month period of January 1, 2011 through June 30, 2011.
This report is submitted by the U.S. Department of Energy (DOE) Carlsbad Field Office and Washington TRU Solutions LLC (the Permittees) in accordance with Permit Part 4, Permit conditions 4.6.2.2 and 4.6.5.2 of the Waste Isolation Pilot Plant (WIPP) Hazardous Waste Facility Permit NM4890139088-TSDF (Permit). This report documents the Volatile Organic Compound (VOC) Monitoring Program and Hydrogen and Methane Monitoring Program results for the 6-month period of July 1, 2011 through December 31, 2011.
Los Alamos National Laboratory (LANL) operations data for CY 2011 mostly fell within the 2008 SWEIS projections. Operation levels for four LANL facilities exceeded the 2008 SWEIS capability projections – Los Alamos Neutron Science Center (LANSCE), Solid Radioactive and Chemical Waste (SRCW), Materials Science Laboratory (MSL) and Radiochemistry Facilities. However, none of these capability increases caused exceedances in waste generation, radioactive air emissions, or NPDES discharge. Several facilities exceeded the SWEIS levels for waste generation quantities; however, all were one-time, non-routine events that do not reflect the day-to-day operations of the Laboratory. In addition, total site-wide waste generation quantities were below SWEIS projections for all waste types, reflecting the overall levels of operations at both the Key and Non-Key Facilities. Although gas and electricity consumption have remained within the 2008 SWEIS limits for utilities, water consumption exceeded the 2008 SWEIS projections by 10 million gallons in CY 2011.
Photosynthesis is the biological process that converts solar energy into chemical energy. Elucidation of the mechanisms of photosynthetic energy conversion at a molecular level is fundamentally important for understanding the biology of photosynthetic organisms, for optimizing biological solar fuels production, and for developing biologically inspired approaches to solar energy conversion. The 2011 Gordon Conference on Photosynthesis will present cutting-edge research focusing on the biochemical aspects of photosynthesis, including: (1) structure, assembly, and function of photosynthetic complexes; (2) the mechanism of water splitting by PSII; (3) light harvesting and quenching; (4) alternative electron transport pathways; (5) biosynthesis of pigments and cofactors; and (6) improvement of photosynthesis for bioenergy and food production. Reflecting the interdisciplinary nature of photosynthesis research, a diverse group of invited speakers will represent a variety of scientific approaches to investigate photosynthesis, such as biochemistry, molecular genetics, structural biology, systems biology, and spectroscopy. Highly interactive poster sessions provide opportunities for graduate students and postdocs to present their work and exchange ideas with leaders in the field. One of the highlights of the Conference is a session featuring short talks by junior investigators selected from the poster presentations. The collegial atmosphere of the Photosynthesis GRC, with programmed discussion sessions as well as informal gatherings in the afternoons and evenings, enables participants to brainstorm, exchange ideas, and forge new collaborations. For the second time, this Conference will be immediately preceded by a Gordon Research Seminar on Photosynthesis (June 11-12, 2011, at the same location), with a focus on 'Photosynthesis, Bioenergy, and the Environment.' The GRS provides an additional opportunity for graduate students and postdocs to present their research, and it provides a mechanism to encourage active participation by junior scientists interested in photosynthesis and its applications.