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DOE OSTI2014

SU-F-BRD-10: Lung IMRT Planning Using Standardized Beam Bouquet Templates

Purpose: We investigate the feasibility of choosing from a small set of standardized templates of beam bouquets (i.e., entire beam configuration settings) for lung IMRT planning to improve planning efficiency and quality consistency, and also to facilitate automated planning. Methods: A set of beam bouquet templates is determined by learning from the beam angle settings in 60 clinical lung IMRT plans. A k-medoids cluster analysis method is used to classify the beam angle configuration into clusters. The value of the average silhouette width is used to determine the ideal number of clusters. The beam arrangements in each medoid of the resulting clusters are taken as the standardized beam bouquet for the cluster, with the corresponding case taken as the reference case. The resulting set of beam bouquet templates was used to re-plan 20 cases randomly selected from the database and the dosimetric quality of the plans was evaluated against the corresponding clinical plans by a paired t-test. The template for each test case was manually selected by a planner based on the match between the test and reference cases. Results: The dosimetric parameters (mean±S.D. in percentage of prescription dose) of the plans using 6 beam bouquet templates and those of the clinical plans, respectively, and the p-values (in parenthesis) are: lung Dmean: 18.8±7.0, 19.2±7.0 (0.28), esophagus Dmean: 32.0±16.3, 34.4±17.9 (0.01), heart Dmean: 19.2±16.5, 19.4±16.6 (0.74), spinal cord D2%: 47.7±18.8, 52.0±20.3 (0.01), PTV dose homogeneity (D2%-D99%): 17.1±15.4, 20.7±12.2 (0.03).The esophagus Dmean, cord D02 and PTV dose homogeneity are statistically better in the plans using the standardized templates, but the improvements (<5%) may not be clinically significant. The other dosimetric parameters are not statistically different. Conclusion: It's feasible to use a small number of standardized beam bouquet templates (e.g. 6) to generate plans with quality comparable to that of clinical plans. Partially supported by NIH/NCI under grant #R21CA161389 and a master research grant by Varian Medical System.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

A prototype, glassless densitometer traceable to primary optical standards for quantitative radiochromic film dosimetry

Purpose: To evaluate a prototype densitometer traceable to primary optical standards and compare its performance to an EPSON Expression{sup ®} 10000XL flatbed scanner (the Epson) for quantitative radiochromic film (RCF) dosimetry. Methods: A prototype traceable laser densitometry system (LDS) was developed to mitigate common film scanning artifacts, such as positional scan dependence and high noise in low-dose regions, by performing point-based measurements of RCF suspended in free-space using coherent light. The LDS and the Epson optical absorbance scales were calibrated up to 3 AU, using reference materials calibrated at a primary standards laboratory and a scanner calibration factor (SCF). Calibrated optical density (OD) was determined for 96 Gafchromic{sup ®} EBT3 film segments before and after irradiation to one of 16 dose levels between 0 and 10 Gy, exposed to {sup 60}Co in a polymethyl-methacrylate (PMMA) phantom. The sensitivity was determined at each dose level and at two rotationally orthogonal readout orientations to obtain the sensitometric response of each RCF dosimetry system. LDS rotational scanning dependence was measured at nine angles between 0°and 180°, due to the expected interference between coherent light and polarizing EBT3 material. The response curves were fit to the analytic functions predicted by two physical response models: the two-parameter single-hit model and the four-parameter percolation model. Results: The LDS and the Epson absorbance measurements were linear to primary optical standards to within 0.2% and 0.3% up to 2 and 1 AU, respectively. At higher densities, the LDS had an over-response (2.5% at 3 AU) and the Epson an under-response (3.1% and 9.8% at 2 and 3 AU, respectively). The LDS and the Epson SCF over the applicable range were 0.968% ± 0.2% and 1.561% ± 0.3%, respectively. The positional scan dependence was evaluated on each digitizer and shown to be mitigated on the LDS, as compared to the Epson. Maximum EBT3 rotational dependence was found to have a strong dependence on dose (0.1% and 34% at 30 mGy and 5 Gy, respectively). The preferred EBT3 polymerization axis angle was constant within experimental uncertainties. In its most sensitive orientation, the LDS-measured EBT3 sensitivity was 7.13 × 10{sup −4} ± 9.2 × 10{sup −6} AU/mGy, which represented a 4.5 fold increase over the Epson of 1.58 × 10{sup −4} ± 9.8 × 10{sup −6} AU/mGy. To first order approximations, EBT3 response was linear up to 500 mGy to within 0.80% and to within 7.5% for the most sensitive LDS and the Epson orientations, respectively. The corresponding single-hit and percolation model relative residual norms were 0.082 and 0.074 for LDS as compared to 0.29 and 0.18 for the Epson, which represented a significant increase in LDS-measured agreement with the simple physical model. Less sensitive LDS and the Epson orientations showed a marked decrease in the physical model agreement, which suggested that suboptimal readout device characteristics may be the origin of the complex sensitometric functional forms currently required for accurate RCF dosimetry. Conclusions: The prototype densitometer was shown to be superior to a conventional scanner for quantitative RCF dosimetry based on physical models of film response. The Epson was shown to be a reliable tool for routine RCF dosimetry in a clinical setting, yet calibration to primary optical standards did not mitigate the necessity for complex, empirical functional form fitting.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-B-213-02: Development of CAMPEP Standards

The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization. In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards. The Symposium will conclude with a panel discussion. Learning Objectives: Recognize the difference between accreditation of an educational program and certification of an individual Identify the two organizations primarily responsible for these tasks Describe the development of educational standards Describe the process by which examination questions are developed GS is Executive Secretary of CAMPEP.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2015

SU-B-213-05: Development of ABR Certification Standards

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2015

MO-F-CAMPUS-T-04: Implementation of a Standardized Monthly Quality Check for Linac Output Management in a Large Multi-Site Clinic

Purpose: This work is to investigate the feasibility of a standardized monthly quality check (QC) of LINAC output determination in a multi-site, multi-LINAC institution. The QC was developed to determine individual LINAC output using the same optimized measurement setup and a constant calibration factor for all machines across the institution. Methods: The QA data over 4 years of 7 Varian machines over four sites, were analyzed. The monthly output constancy checks were performed using a fixed source-to-chamber-distance (SCD), with no couch position adjustment throughout the measurement cycle for all the photon energies: 6 and 18MV, and electron energies: 6, 9, 12, 16 and 20 MeV. The constant monthly output calibration factor (Nconst) was determined by averaging the machines’ output data, acquired with the same monthly ion chamber. If a different monthly ion chamber was used, Nconst was then re-normalized to consider its different NDW,Co-60. Here, the possible changes of Nconst over 4 years have been tracked, and the precision of output results based on this standardized monthly QA program relative to the TG-51 calibration for each machine was calculated. Any outlier of the group was investigated. Results: The possible changes of Nconst varied between 0–0.9% over 4 years. The normalization of absorbed-dose-to-water calibration factors corrects for up to 3.3% variations of different monthly QA chambers. The LINAC output precision based on this standardized monthly QC relative to the TG-51 output calibration is within 1% for 6MV photon energy and 2% for 18MV and all the electron energies. A human error in one TG-51 report was found through a close scrutiny of outlier data. Conclusion: This standardized QC allows for a reasonably simplified, precise and robust monthly LINAC output constancy check, with the increased sensitivity needed to detect possible human errors and machine problems.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2018

Search for standard model production of four top quarks with same-sign and multilepton final states in proton–proton collisions at $\sqrt{s} = 13\,\text {TeV} $

A search for standard model production of four top quarks ( $\mathrm {t}\overline{\mathrm {t}} \mathrm {t}\overline{\mathrm {t}} $ ) is reported using events containing at least three leptons ( $\mathrm {e}, \mathrm {\mu }$ ) or a same-sign lepton pair. The events are produced in proton–proton collisions at a center-of-mass energy of 13 $\,\text {TeV}$ at the LHC, and the data sample, recorded in 2016, corresponds to an integrated luminosity of 35.9 $\,\text {fb}^{-1}$ . Jet multiplicity and flavor are used to enhance signal sensitivity, and dedicated control regions are used to constrain the dominant backgrounds. The observed and expected signal significances are, respectively, 1.6 and 1.0 standard deviations, and the $\mathrm {t}\overline{\mathrm {t}} \mathrm {t}\overline{\mathrm {t}} $ cross section is measured to be $16.9^{+13.8-11.4}$ $\,\text {fb}$ , in agreement with next-to-leading-order standard model predictions. These results are also used to constrain the Yukawa coupling between the top quark and the Higgs boson to be less than 2.1 times its expected standard model value at 95% confidence level.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2014

Beyond standard model searches in the MiniBooNE experiment

The MiniBooNE experiment has contributed substantially to beyond standard model searches in the neutrino sector. The experiment was originally designed to test the Δ m 2 ~ 1 eV 2 region of the sterile neutrino hypothesis by observing ν e ( ν - e ) charged current quasielastic signals from a ν μ ( ν - μ ) beam. MiniBooNE observed excesses of ν e and ν - e candidate events in neutrino and antineutrino mode, respectively. To date, these excesses have not been explained within the neutrino standard model ( ν SM); the standard model extended for three massive neutrinos. Confirmation is required by future experiments such as MicroBooNE. MiniBooNE also provided an opportunity for precision studies of Lorentz violation. The results set strict limits for the first time on several parameters of the standard-model extension, the generic formalism for considering Lorentz violation. Most recently, an extension to MiniBooNE running, with a beam tuned in beam-dump mode, is being performed to search for dark sector particles. In addition, this review describes these studies, demonstrating that short baseline neutrino experiments are rich environments in new physics searches.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2023

Conduct of Operations and Nuclear Criticality Safety Standards

Since the beginning of the nuclear age in 1943, there have been 22 criticality accidents in process facilities worldwide in which fissionable materials were processed by hand for various purposes. Of these 22 process criticality accidents, 16 involved faulty or flawed conduct of operations. Most of these process accidents (17 of 22) occurred before 1970, mostly due to the implementation of formal conduct of operations—such as the use of operating procedures and training—and the use of consensus standards for nuclear criticality safety (NCS). Obviously, the nuclear facilities applied lessons learned from their accident history, and the rate of criticality accidents was significantly reduced as a result. Over the years, it has been emphasized in NCS training courses and other venues in the United States that the consensus standards, such as ASA N6.1-1964, were the key contributors to this reduction in accidents. The formality of operations required to implement and apply the standards at a facility is also a crucial prerequisite that must be sufficiently robust to ensure NCS. This prerequisite is crucial to success fully implement the NCS consensus and other safety standards at a site.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

DOE OSTI2026

Progress in the development of the community Particle Accelerator Lattice Standard (PALS)

The Particle Accelerator Lattice Standard (PALS) is a community effort to create an open standard to promote lattice information exchange for particle accelerators. PALS development is a community-wide international effort involving accelerator physicists from multiple institutions. While it started as a lattice standard for beam dynamics simulations, it is now being extended to support other particle accelerator activities, in particular accelerator operation. With new accelerators that are becoming more complex, larger collaborations and the increasing imprint of artificial intelligence in all accelerator activities (from design to operation to workforce development), the imperative for a common, standardized accelerator ontology has been transitioning from “nice-to-have” to “must-have”. We will present the status of the project, its relations to other projects, including to two of the particle accelerator projects of the newly announced US DOE Genesis Mission: the Multi-Office Accelerator Team (MOAT) project and the Nuclear physics AI-Ready Accelerator Data (NARAD) project.

Brynes, A. [Science and Technology Facilities Coun↗

DOE OSTI2013

Summary Report: Development of a New ASTM Standard Test Method for Phase Change Materials

An ASTM International task group was formed with representatives from research organizations, PCM and insulation manufacturers, testing laboratories, etc., to develop an ASTM standard test method, using a heat flow meter apparatus (HFMA), to make heat-flow measurements under prescribed dynamic, or non steady-state, conditions. The HFMA is typically used for measuring steady-state thermal transmission properties of materials, following ASTM C518. The new ‘dynamic’ test method is based on a modification of the C518 test method, for measuring volumetric specific heat of regular (i.e. with no PCM) thermal insulation materials. The proposed test method describes the methodology for using a HFMA for measuring thermal storage properties of phase change materials and products. It requires the measurement of non-steady-state heat flow into or out of a flat slab specimen to determine the stored energy (i.e. enthalpy) change as a function of temperature. In particular, this test method is intended to measure the sensible and latent heat storage capacity of products incorporating phase-change materials (PCM). The thermal storage capacity of a PCM is well defined via four parameters: specific heats of both solid and liquid phases, phase change temperature(s) and phase change enthalpy. This report provides brief summaries of the proposed standard test method and the standard development related activities at Oak Ridge National Laboratory (ORNL) during fiscal year 2013 (FY13). The draft standard document is also provided as an appendix.

dynamic testing↗

DOE OSTI2013

Data Availability in Appliance Standards and Labeling Program Development and Evaluation

In this report, we describe the necessary data inputs for both standards development and program evaluation and perform an initial assessment of the availability and uncertainty of those data inputs in China. For standards development, we find that China and its standards and labeling program administrators currently has access to the basic market and technical data needed for conducting market and technology assessment and technological and economic analyses. Some data, such as shipments data, is readily available from the China Energy Label product registration database while the availability of other data, including average unit energy consumption, prices and design options, needs improvement. Unlike some other countries such as the United States, most of the necessary data for conducting standards development analyses are not publicly available or compiled in a consolidated data source. In addition, improved data on design and efficiency options as well as cost data (e.g., manufacturing costs, mark-ups, production and product use-phase costs) – key inputs to several technoeconomic analyses – are particularly in need given China’s unconsolidated manufacturing industry. For program evaluation, we find that while China can conduct simple savings evaluations on its incentive programs with the data it currently has available from the Ministry of Finance – the program administrator, the savings estimates produced by such an evaluation will carry high uncertainty. As such, China could benefit from an increase in surveying and metering in the next one to three years to decrease the uncertainty surrounding key data points such as unit energy savings and free ridership.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2015

242 PU Standards Documentation Package

The standards documented in this package are composed of plutonium oxide. One set of standards was fabricated from 84% 242 pu material and the other 89% 242 pu material. They were specifically designed to be used as calibration standards for thermal neutron counters (TNCs). The procedure used to prepare these standards is part of the documentation package.

07 ISOTOPE AND RADIATION SOURCES↗

DOE OSTI2015

Development of ASTM Standard for SiC-SiC Joint Testing Final Scientific/Technical Report

As the nuclear industry moves to advanced ceramic based materials for cladding and core structural materials for a variety of advanced reactors, new standards and test methods are required for material development and licensing purposes. For example, General Atomics (GA) is actively developing silicon carbide (SiC) based composite cladding (SiC-SiC) for its Energy Multiplier Module (EM2), a high efficiency gas cooled fast reactor. Through DOE funding via the advanced reactor concept program, GA developed a new test method for the nominal joint strength of an endplug sealed to advanced ceramic tubes, Fig. 1-1, at ambient and elevated temperatures called the endplug pushout (EPPO) test. This test utilizes widely available universal mechanical testers coupled with clam shell heaters, and specimen size is relatively small, making it a viable post irradiation test method. The culmination of this effort was a draft of an ASTM test standard that will be submitted for approval to the ASTM C28 ceramic committee. Once the standard has been vetted by the ceramics test community, an industry wide standard methodology to test joined tubular ceramic components will be available for the entire nuclear materials community.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2016

Community-Wide Zero Energy Ready Home Standard

This report outlines the steps a developer can use when looking to create and implement higher performance standards such as the U.S. Department of Energy (DOE) Zero Energy Ready Home (ZERH) standards in a community. The report also describes the specific examples of how this process was followed by a developer, Forest City, in the Stapleton community in Denver, Colorado. IBACOS described the steps used to begin to bring the DOE ZERH standard to the Forest City Stapleton community based on 15 years of community-scale development work done by IBACOS. As a result of this prior IBACOS work, the team gained an understanding of the various components that a master developer needs to consider and created strategies for incorporating those components in the initial phases of development to achieve higher performance buildings in the community. An automated scoring system can be used to perform an internal audit that provides a detailed and consistent evaluation of how several homes under construction or builders' floor plans compare with the requirements of the DOE Zero Energy Ready Home program. This audit can be performed multiple times at specific milestones during construction to allow the builder to make changes as needed throughout construction for the project to meet Zero Energy Ready Home standards. This scoring system also can be used to analyze a builder's current construction practices and design.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2012

Antineutrino Oscillations and a Search for Non-standard Interactions with the MINOS

MINOS searches for neutrino oscillations using the disappearance of muon neutrinos from the NuMI beam at Fermilab between two detectors. The Near Detector, located near the source, measures the beam composition before flavor change occurs. The energy spectrum is measured again at the Far Detector after neutrinos travel a distance. The mixing angle and mass splitting between the second and third mass states are extracted from the energy dependent difference between the spectra at the two detectors. NuMI is able to produce an antineutrino-enhanced beam as well as a neutrino-enhanced beam. Collecting data in antineutrino-mode allows the direct measurement of antineutrino oscillation parameters. From the analysis of the antineutrino mode data we measure $|\Delta\bar{m}^{2}_{\text{atm}}| = 2.62^{+0.31}_{-0.28}\times10^{-3}\text{eV}^{2}$ and $\sin^{2}(2\bar{\theta})_{23} = 0.95^{+0.10}_{-0.11}$, which is the most precise measurement of antineutrino oscillation parameters to date. A difference between neutrino and antineutrino oscillation parameters may indicate new physics involving interactions that are not part of the Standard Model, called non-standard interactions, that alter the apparent disappearance probability. Collecting data in neutrino and antineutrino mode independently allows a direct search for non-standard interactions. In this dissertation non-standard interactions are constrained by a combined analysis of neutrino and antineutrino datasets and no evidence of such interactions is found.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2012

Search for the Standard Model Higgs boson at D0 in the $\mu~+~\tau({\rm hadrons})~+~{\rm 2\ jets}$ final state

The Standard Model has been a successful theory in various aspects. It predicted and led to discovery of many new particles, including the Higgs boson recently found, the last missing piece of the Standard Model. The Higgs mechanism allows the vector bosons and fermions to be massive via the electroweak symmetry breaking. This dissertation presents the search of the Standard Model Higgs through the decay products: one muon, one hadronically decaying tau, and two or more jets using the full 9.7 fb$^{-1}$ of Tevatron collider Run II data set collected in the Dzero detector at Fermilab. The main production channels are gluon-gluon fusion, vector boson fusion, and Higgs production associated with a $W/Z$ boson. No evidence of the Standard Model Higgs boson is observed in these channels with hypothesized Higgs mass between 105 GeV and 150 GeV, but the data do not exclude it either. We set the upper limits on the ratio of the 95% CL exclusion to the SM Higgs cross section. Combining with other analyses in Tevatron, the Higgs mass is ruled out at 95 % confidence level between 147 and 180 GeV, and a 2.9 $\sigma$ excess of events indicates a Higgs boson possibly lies in the mass range from 115 to 140 GeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2016

ANSI/ASHRAE/IES Standard 90.1-2010 Performance Rating Method Reference Manual

This document is intended to be a reference manual for the Appendix G Performance Rating Method (PRM) of ANSI/ASHRAE/IES Standard 90.1- 2010 (Standard 90.1-2010).The PRM is used for rating the energy efficiency of commercial and high-rise residential buildings with designs that exceed the requirements of Standard 90.1. The procedures and processes described in this manual are designed to provide consistency and accuracy by filling in gaps and providing additional details needed by users of the PRM. It should be noted that this document is created independently from ASHRAE and SSPC 90.1 and is not sanctioned nor approved by either of those entities . Potential users of this manual include energy modelers, software developers and implementers of “beyond code” energy programs. Energy modelers using ASHRAE Standard 90.1-2010 for beyond code programs can use this document as a reference manual for interpreting requirements of the Performance Rating method. Software developers, developing tools for automated creation of the baseline model can use this reference manual as a guideline for developing the rules for the baseline model.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2014

Solar PV O&M Standards and Best Practices - Existing Gaps and Improvement Efforts

As greater numbers of photovoltaic (PV) systems are being installed, operations & maintenance (O&M) activities will need to be performed to ensure the PV system is operating as designed over its useful lifetime. To mitigate risks to PV system availability and performance, standardized procedures for O&M activities are needed to ensure high reliability and long-term system bankability. Efforts are just getting underway to address the need for standard O&M procedures as PV gains a larger share of U.S. generation capacity. Due to the existing landscape of how and where PV is installed, including distributed generation from small and medium PV systems, as well as large, centralized utility-scale PV, O&M activities will require different levels of expertise and reporting, making standards even more important. This report summarizes recent efforts made by solar industry stakeholders to identify the existing standards and best practices applied to solar PV O&M activities, and determine the gaps that have yet to be, or are currently being addressed by industry.

14 SOLAR ENERGY↗