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Adiabatic release measurements in aluminum between 400 and 1200 GPa: Characterization of aluminum as a shock standard in the multimegabar regime

Aluminum has been used prolifically as an impedance matching standard in the multimegabar regime (1 Mbar = 100 GPa), particularly in nuclear driven, early laser driven, and early magnetically driven flyer plate experiments. The accuracy of these impedance matching measurements depends upon the knowledge of both the Hugoniot and release or reshock response of aluminum. Here, we present the results of several adiabatic release measurements of aluminum from ~400–1200 GPa states along the principal Hugoniot using full density polymethylpentene (commonly known as TPX), and both ~190 and ~110 mg/cc silica aerogel standards. Additionally, these data were analyzed within the framework of a simple, analytical model that was motivated by a first-principles molecular dynamics investigation into the release response of aluminum, as well as by a survey of the release response determined from several tabular equations of state for aluminum. Combined, this theoretical and experimental study provides a method to perform impedance matching calculations without the need to appeal to any tabular equation of state for aluminum. Furthermore, as an analytical model, this method allows for propagation of all uncertainty, including the random measurement uncertainties and the systematic uncertainties of the Hugoniot and release response of aluminum. This work establishes aluminum for use as a high-precision standard for impedance matching in the multimegabar regime.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Developing quartz and molybdenum as impedance-matching standards in the 100-Mbar regime

We present quartz and molybdenum single-shock Hugoniot data to 62 Mbar and 120 Mbar, respectively. Quartz and molybdenum are attractive standard materials for Hugoniot equation-of-state impedance-matching studies. Quartz is advantageous because a reflecting shock front is supported above ~1 Mbar whose velocity can be tracked in situ to very high accuracy. Molybdenum's relatively high impedance makes it a more appropriate standard for other high-impedance material studies to avoid large departures from the standard principal Hugoniot upon release or reshock into the sample. Extensive measurements already exist for both materials up to about 10 Mbar and 10 eV, but new high-energy-density facilities and techniques have extended the experimentally accessible pressure range to >100 Mbar. The data presented here indicate which modern equation-of-state models can be reliably extended into newly-accessible experimental regimes.

36 MATERIALS SCIENCE↗

Photonuclear cross sections for 197 Au: An update on the gold standard

Cross sections for the 197 Au(γ, n) reaction are broadly used in nuclear physics as a standard for normalizing photonuclear reaction cross-section data at photon beam energies above approximately 8 MeV. In this paper, we report cross-section measurements for the 197 Au(γ, n) 196 Au g+m1 reaction at beam energies from 13 to 31 MeV. Our measurements provide the first cross-section data for this reaction at beam energies above 20 MeV, enabling the use of this reaction as a cross-section standard up to 30 MeV. Also, this work provides first cross-section measurements for the 197 Au(γ, n) 196 Au m2 reaction. In addition, we measured cross-section data for the 197 Au(γ, 3n) 194 Au reaction, which can be used as a cross-section standard above about 25 MeV. These measurements were performed using a new target activation method that is based on the angle-energy correlation of the laser Compton- scattered photon beams at the High Intensity Gamma-ray Source (HIγS). The technique enables measuring photonuclear reaction cross-sections at several discrete beam energies concurrently via a single irradiation on a stack of different targets. Measurements were carried out by irradiating a stack of concentric-ring targets consisting of Au, TiO 2 , Zn, Os, and Au (in order of the γ-ray beam direction). Our data for the 197 Au(γ,n) 196 Au g+m1 reaction in the energy range of 13 to 20 MeV are in good agreement with existing ones measured using monoenergetic γ-ray beams, but differ from data acquired using a bremsstrahlung γ-ray beam. Also, above 18 MeV, our data for the 197 Au(γ,n) 196 Au g+m1 and 197 Au(γ,n) 196 Au m2 reactions differ significantly from the most recent TENDL and JENDL evaluations, suggesting a need to update these data libraries. Furthermore, the TENDL evaluation and existing data are consistent with our data for the 197 Au(γ,3n) reaction, but differ significantly from the JENDL evaluation above 26 MeV.

190 ≤ A ≤ 219↗

Search for standard model Higgs boson production in association with a W boson using a matrix element technique at CDF in pp̄ collisions at √s=1.96 TeV

This paper presents a search for standard model Higgs boson production in association with a W boson using events recorded by the CDF experiment in a data set corresponding to an integrated luminosity of 5.6 fb⁻¹. The search is performed using a matrix element technique in which the signal and background hypotheses are used to create a powerful discriminator. The discriminant output distributions for signal and background are fit to the observed events using a binned likelihood approach to search for the Higgs boson signal. We find no evidence for a Higgs boson, and 95% confidence level (C.L.) upper limits are set on σ(pp̄→WH)×B(H→bb¯). The observed limits range from 3.5 to 37.6 relative to the standard model expectation for Higgs boson masses between mH=100 GeV/c² and mH=150 GeV/c². The 95% C.L. expected limit is estimated from the median of an ensemble of simulated experiments and varies between 2.9 and 32.7 relative to the production rate predicted by the standard model over the Higgs boson mass range studied.

Aaltonen, T.↗

IEC 61850: Technology Standards and Cyber-Security Threats

Substations constitute a fundamental part in providing reliable electricity to consumers. For a substation to maintain electricity reliability and its own real-time operability, communication between its components is inevitable. Before the emergence of IEC 61850, inter-substation communication was established via expensive copper wires with limited capabilities. IEC 61850 is the standard set by the International Electrotechnical Commission (IEC) Technical Committee Number 57 Working Group 10 and IEEE for Ethernet (IEEE 802.3)-based communication in electrical substations. Like many power grid systems standards, IEC 61850 was set without extensive consideration for critical security measures. This paper discusses IEC 61850 technology standards and applications thoroughly and points out major security vulnerabilities it introduces in the context of current cyber-physical smart grid systems.

97 MATHEMATICS AND COMPUTING↗

The Vertebrate Breed Ontology: Toward Effective Breed Data Standardization

Abstract Background Limited universally-adopted data standards in veterinary medicine hinder data interoperability and therefore integration and comparison; this ultimately impedes the application of existing information-based tools to support advancement in diagnostics, treatments, and precision medicine. Hypothesis/Objectives A single, coherent, logic-based standard for documenting breed names in health, production, and research-related records will improve data use capabilities in veterinary and comparative medicine. Animals No live animals were used. Methods The Vertebrate Breed Ontology (VBO) was created from breed names and related information compiled from the Food and Agriculture Organization of the United Nations, breed registries, communities, and experts, using manual and computational approaches. Each breed is represented by a VBO term that includes breed information and provenance as metadata. VBO terms are classified using description logic to allow computational applications and Artificial Intelligence–readiness. Results VBO is an open, community-driven ontology representing over 19 500 livestock and companion animal breed concepts covering 49 species. Breeds are classified based on community and expert conventions (e.g., cattle breed) and supported by relations to the breed's genus and species indicated by National Center for Biotechnology Information (NCBI) Taxonomy terms. Relationships between VBO terms (e.g., relating breeds to their foundation stock) provide additional context to support advanced data analytics. VBO term metadata includes synonyms, breed identifiers/codes, and attributed cross-references to other databases. Conclusion and Clinical Importance The adoption of VBO as a standard for breed names in databases and veterinary electronic health records enhances veterinary data interoperability and computability, supporting precision medicine.

Veterinary Sciences↗

Need for LWR metrology standardization: the imec roughness protocol

© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). As semiconductor technology keeps moving forward, undeterred by the many challenges ahead, one specific deliverable is capturing the attention of many experts in the field: line width roughness (LWR) specifications are expected to be <2 nm in the near term, and to drop below 1 nm in just a few years. This is a daunting challenge and engineers throughout the industry are trying to meet these targets using every means at their disposal. However, although current efforts are surely admirable, we believe they are not enough. The fact is that a specification has a meaning only if there is an agreed methodology to verify if the criterion is met or not. Such standardization is critical in any field of science and technology and the question that we need to ask ourselves today is whether we have a standardized LWR metrology or not. In other words, if a single reference sample were provided, would everyone measuring it get reasonably comparable results? We came to realize that this is not the case and that the observed spread in the results throughout the industry is quite large. In our opinion, this makes the comparison of LWR data among institutions, or to a specification, very difficult. We report the spread of measured LWR data across the semiconductor industry. We investigate the impact of image acquisition, measurement algorithm, and frequency analysis parameters on LWR metrology. We review critically some of the International Technology Roadmap for Semiconductors (ITRS) metrology guidelines [such as measurement box length >2 μm and the need to correct for scanning electron microscope (SEM) noise]. We compare the SEM roughness results to AFM measurements. Finally, we propose a standardized LWR measurement protocol - the imec roughness protocol - intended to ensure that every time LWR measurements are compared (from various sources or to specifications), the comparison is sensible and sound. We deeply believe that the industry is at a point where it is imperative to guarantee that when talking about a critical parameter such as LWR, everyone speaks the same language, which is not currently the case.

Lorusso, Gian Francesco↗

Binary pseudo-random array standard for extreme ultraviolet lithography tool characterization

Extreme ultraviolet (EUV) imaging tools play a crucial role in EUV lithography. Achieving high accuracy in EUV metrology is essential for advanced semiconductor manufacturing. A thorough characterization of the instrumentation in use is required. Binary pseudo-random arrays (BPRAs) are an established standard for calibrating and characterizing optical instruments in the frequency domain. Here, we expand the BPRA standard to applications in EUV imaging. To extend the technology to the EUV spectral range, a high-resolution BPRA target with the smallest feature size of 40 nm is developed. The EUV BPRA target establishes an in situ and portable calibration and alignment standard for EUV imaging. The target is patterned by means of electron-beam lithography, using a nickel absorber with a thickness of 39 nm. The substrate is a 4″ silicon wafer with a molybdenum/silicon multilayer coating. To demonstrate the efficacy of the target and develop the instrument calibration protocol, the target is imaged on the Sharp Hyper-NA Actinic Reticle Review Project EUV mask microscope. Power spectral density (PSD) data are presented. The characteristics of the imaging system are imprinted on the PSD. The modulation transfer function is extracted from the PSD data. A partially coherent imaging model is used as a reference to the experimental results.

BPRA↗

WE-D-9A-03: CSDF: A Color Extension of the Grayscale Standard Display Function

Purpose: Use of color images in medical imaging has increased significantly the last few years. As of today there is no agreed standard on how color information needs to be visualized on medical color displays, resulting into large variability of color appearance and it making consistency and quality assurance a challenge. This paper presents a proposal for an extension of DICOM GSDF towards color. Methods: Visualization needs for several color modalities (multimodality imaging, nuclear medicine, digital pathology, quantitative imaging applications…) have been studied. On this basis a proposal was made for desired color behavior of color medical display systems and its behavior and effect on color medical images was analyzed. Results: Several medical color modalities could benefit from perceptually linear color visualization for similar reasons as why GSDF was put in place for greyscale medical images. An extension of the GSDF (Greyscale Standard Display Function) to color is proposed: CSDF (color standard display function). CSDF is based on deltaE2000 and offers a perceptually linear color behavior. CSDF uses GSDF as its neutral grey behavior. A comparison between sRGB/GSDF and CSDF confirms that CSDF significantly improves perceptual color linearity. Furthermore, results also indicate that because of the improved perceptual linearity, CSDF has the potential to increase perceived contrast of clinically relevant color features. Conclusion: There is a need for an extension of GSDF towards color visualization in order to guarantee consistency and quality. A first proposal (CSDF) for such extension has been made. Behavior of a CSDF calibrated display has been characterized and compared with sRGB/GSDF behavior. First results indicate that CSDF could have a positive influence on perceived contrast of clinically relevant color features and could offer benefits for quantitative imaging applications. Authors are employees of Barco Healthcare.

60 APPLIED LIFE SCIENCES↗

SU-E-T-552: Monte Carlo Calculation of Correction Factors for a Free-Air Ionization Chamber in Support of a National Air-Kerma Standard for Electronic Brachytherapy

Purpose: To use Monte Carlo radiation transport methods to calculate correction factors for a free-air ionization chamber in support of a national air-kerma standard for low-energy, miniature x-ray sources used for electronic brachytherapy (eBx). Methods: The NIST is establishing a calibration service for well-type ionization chambers used to characterize the strength of eBx sources prior to clinical use. The calibration approach involves establishing the well-chamber’s response to an eBx source whose air-kerma rate at a 50 cm distance is determined through a primary measurement performed using the Lamperti free-air ionization chamber. However, the free-air chamber measurements of charge or current can only be related to the reference air-kerma standard after applying several corrections, some of which are best determined via Monte Carlo simulation. To this end, a detailed geometric model of the Lamperti chamber was developed in the EGSnrc code based on the engineering drawings of the instrument. The egs-fac user code in EGSnrc was then used to calculate energy-dependent correction factors which account for missing or undesired ionization arising from effects such as: (1) attenuation and scatter of the x-rays in air; (2) primary electrons escaping the charge collection region; (3) lack of charged particle equilibrium; (4) atomic fluorescence and bremsstrahlung radiation. Results: Energy-dependent correction factors were calculated assuming a monoenergetic point source with the photon energy ranging from 2 keV to 60 keV in 2 keV increments. Sufficient photon histories were simulated so that the Monte Carlo statistical uncertainty of the correction factors was less than 0.01%. The correction factors for a specific eBx source will be determined by integrating these tabulated results over its measured x-ray spectrum. Conclusion: The correction factors calculated in this work are important for establishing a national standard for eBx which will help ensure that dose is accurately and consistently delivered to patients.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

TU-AB-BRA-04: Quantitative Radiomics: Sensitivity of PET Textural Features to Image Acquisition and Reconstruction Parameters Implies the Need for Standards

Purpose: Despite increased use of heterogeneity metrics for PET imaging, standards for metrics such as textural features have yet to be developed. We evaluated the quantitative variability caused by image acquisition and reconstruction parameters on PET textural features. Methods: PET images of the NEMA IQ phantom were simulated with realistic image acquisition noise. 35 features based on intensity histograms (IH), co-occurrence matrices (COM), neighborhood-difference matrices (NDM), and zone-size matrices (ZSM) were evaluated within lesions (13, 17, 22, 28, 33 mm diameter). Variability in metrics across 50 independent images was evaluated as percent difference from mean for three phantom girths (850, 1030, 1200 mm) and two OSEM reconstructions (2 iterations, 28 subsets, 5 mm FWHM filtration vs 6 iterations, 28 subsets, 8.6 mm FWHM filtration). Also, patient sample size to detect a clinical effect of 30% with Bonferroni-corrected α=0.001 and 95% power was estimated. Results: As a class, NDM features demonstrated greatest sensitivity in means (5–50% difference for medium girth and reconstruction comparisons and 10–100% for large girth comparisons). Some IH features (standard deviation, energy, entropy) had variability below 10% for all sensitivity studies, while others (kurtosis, skewness) had variability above 30%. COM and ZSM features had complex sensitivities; correlation, energy, entropy (COM) and zone percentage, short-zone emphasis, zone-size non-uniformity (ZSM) had variability less than 5% while other metrics had differences up to 30%. Trends were similar for sample size estimation; for example, coarseness, contrast, and strength required 12, 38, and 52 patients to detect a 30% effect for the small girth case but 38, 88, and 128 patients in the large girth case. Conclusion: The sensitivity of PET textural features to image acquisition and reconstruction parameters is large and feature-dependent. Standards are needed to ensure that prospective trials which incorporate textural features are properly designed to detect clinical endpoints. Supported by NIH grants R01 CA169072, U01 CA148131, NCI Contract (SAIC-Frederick) 24XS036-004, and a research contract from GE Healthcare.

60 APPLIED LIFE SCIENCES↗

SU-F-J-100: Standardized Biodistribution Template for Nuclear Medicine Dosimetry Collection and Reporting

Purpose: As the field of Nuclear Medicine moves forward with efforts to integrate radiation dosimetry into clinical practice we can identify the challenge posed by the lack of standardized dose calculation methods and protocols. All personalized internal dosimetry is derived by projecting biodistribution measurements into dosimetry calculations. In an effort to standardize organization of data and its reporting, we have developed, as a sequel to the EANM recommendation of “Good Dosimetry Reporting”, a freely available biodistribution template, which can be used to create a common point of reference for dosimetry data. It can be disseminated, interpreted, and used for method development widely across the field. Methods: A generalized biodistribution template was built in a comma delineated format (.csv) to be completed by users performing biodistribution measurements. The template is available for free download. The download site includes instructions and other usage details on the template. Results: This is a new resource developed for the community. It is our hope that users will consider integrating it into their dosimetry operations. Having biodistribution data available and easily accessible for all patients processed is a strategy for organizing large amounts of information. It may enable users to create their own databases that can be analyzed for multiple aspects of dosimetry operations. Furthermore, it enables population data to easily be reprocessed using different dosimetry methodologies. With respect to dosimetry-related research and publications, the biodistribution template can be included as supplementary material, and will allow others in the community to better compare calculations and results achieved. Conclusion: As dosimetry in nuclear medicine become more routinely applied in clinical applications, we, as a field, need to develop the infrastructure for handling large amounts of data. Our organ level biodistribution template can be used as a standard format for data collection, organization, as well as for dosimetry research and software development.

60 APPLIED LIFE SCIENCES↗

SU-F-T-23: Correspondence Factor Correction Coefficient for Commissioning of Leipzig and Valencia Applicators with the Standard Imaging IVB 1000

Purpose: To determine the correction factor of the correspondence factor for the Standard Imaging IVB 1000 well chamber for commissioning of Elekta’s Leipzig and Valencia skin applicators. Methods: The Leipzig and Valencia applicators are designed to treat small skin lesions by collimating irradiation to the treatment area. Published output factors are used to calculate dose rates for clinical treatments. To validate onsite applicators, a correspondence factor (CFrev) is measured and compared to published values. The published CFrev is based on well chamber model SI HDR 1000 Plus. The CFrev is determined by correlating raw values of the source calibration setup (Rcal,raw) and values taken when each applicator is mounted on the same well chamber with an adapter (Rapp,raw). The CFrev is calculated by using the equation CFrev =Rapp,raw/Rcal,raw. The CFrev was measured for each applicator in both the SI HDR 1000 Plus and the SI IVB 1000. A correction factor, CFIVB for the SI IVB 1000 was determined by finding the ratio of CFrev (SI IVB 1000) and CFrev (SI HDR 1000 Plus). Results: The average correction factors at dwell position 1121 were found to be 1.073, 1.039, 1.209, 1.091, and 1.058 for the Valencia V2, Valencia V3, Leipzig H1, Leipzig H2, and Leipzig H3 respectively. There were no significant variations in the correction factor for dwell positions 1119 through 1121. Conclusion: By using the appropriate correction factor, the correspondence factors for the Leipzig and Valencia surface applicators can be validated with the Standard Imaging IVB 1000. This allows users to correlate their measurements with the Standard Imaging IVB 1000 to the published data. The correction factor is included in the equation for the CFrev as follows: CFrev= Rapp,raw/(CFIVB*Rcal,raw). Each individual applicator has its own correction factor, so care must be taken that the appropriate factor is used.

60 APPLIED LIFE SCIENCES↗

SU-F-T-503: Trajectory Modulated Arc Therapy of Intracranial Lesions: Development of a Standardized Path-Based Technique for Fully Dynamic Couch-Gantry Modulated Treatments

Purpose: The integration of couch motion during arc delivery is necessitated to enable irradiation trajectories such as coronal arcs, and to enhance the geometrical sampling for dynamic deliveries to the highest extent. To enable such capability, a platform of Trajectory Modulated Arc Therapy (TMAT) is developed in conjunction with standardized noncollisional dynamic path-set for irradiation of intracranial lesions. Methods: A generalized path-set was constructed through the combination of sagittal arcs (45 degrees from the CAX), axial arcs, and coronal arcs produced through modulation of the dynamic rotation of couch. The standardized path was implemented in a contiguous manner enabling the formation of fully automated sub-trajectories to provide maximal geometrical convergence with minimal number of arcs. Progressive sampling technique is used for direct aperture optimization of the MLCs and the selection of couch positions across the control points. Dosimetry of the resulting plans was assessed relative to clinically delivered plans. Using the TrueBeam Developer Mode, plan deliverability was tested. Results: Treatment planning of TMAT sub-trajectories for central, anterior and posterior tumor sites with volumes ranging from 4.75cc to 107cc demonstrated radically reduced doses to the critical OARs when compared to the clinically treated VMAT. Specifically, percentage reduction in mean dose for critical organs such as brainstem, cochlea, and optic nerve are found to be as low as 74±15%, 50±26% and 74±30% respectively as compared to VMAT. Conformity Index, defined as the ratio of tumor volume (VPTV) and 100% dose volume (V(D100%)), was reduced up to 12% while the Gradient Index, defined as V(D100%)/V(D50%), was concurrently improved by up to 14%. Conclusion: An automated standardized trajectory with dynamically modulated couch-gantry arcs has been developed for intracranial radiotherapy. Through the incorporation of coronal arcs, it is demonstrated that significantly reduced OAR doses can be achieved relative to clinically treated patient plans via VMAT. Research Grant Funding Support by Varian Medical Systems.

60 APPLIED LIFE SCIENCES↗

Sci-Sat AM: Radiation Dosimetry and Practical Therapy Solutions - 09: Stability of a water calorimetry system as a primary standard for absorbed dose to water

Purpose: To investigate the stability of a water calorimetry system as a primary standard for absorbed dose to water using measurements performed in cobalt-60 and high-energy linac photon beams over a span of more than a decade. Methods: Calorimetry measures adsorbed dose directly by recording the amount of heat created when ionizing radiation passes through matter. The radiation-induced temperature rise was measured using two thermistors calibrated against the NRC temperature primary standard, using an AC bridge with lock-in amplifier for precise measurement. The calorimeter system was operated under thermal equilibrium at 4 °C (to eliminate convection) with drifts in water temperature less than 0.1 mK/min. Seven water vessels of various designs were used to make repeated measurements over the course of 17 years. Results: The standard uncertainty achieved for a set of ten calorimeter measurements (4 Gy delivered) was generally well below 0.15 % while the variation between multiple sets for a given vessel was consistent with this value. The long-term stability of the system combined with inter-vessel variations indicated that there was good control of the radiochemistry (chemical heat defect). Conclusions: The measurements performed over a period of several years showed that the combined water calorimeters showed stability at +/− 0.25 % level. Thus, rather than relying on a particular vessel as an artifact one can realize the Gray through the more generalized method of combining a glass vessel, high-purity water and thermistor probes. This provides increased robustness in the dissemination of absorbed dose to Canadian users.

60 APPLIED LIFE SCIENCES↗

Virus species names have been standardized; virus names remain unchanged

Virus taxonomy, comprising classification and nomenclature, is regulated by the International Committee on Taxonomy of Viruses (ICTV). Taxon names are standardized to facilitate recognition and communication, with defined suffixes for each rank (e.g., the names of orders, families, and genera end in -virales, -viridae, and -virus, respectively). However, until recently, a standard format for species names was lacking. In 2021, following extensive discussion and community consultation, the ICTV decided to adopt a standardized binomial (Linnaean) format for virus species names, consisting of the genus name followed by a "freeform" species epithet. Previously assigned virus species names that were non-compliant with the binomial format have been fully updated. In contrast to taxon names regulated by the ICTV, the names of viruses, or "common" names, such as yellow fever virus or human immunodeficiency virus, are not under the remit of the ICTV and have not been changed.

Zerbini, F Murilo↗

Microbiome Metadata Standards: Report of the National Microbiome Data Collaborative’s Workshop and Follow-On Activities

Microbiome samples are inherently defined by the environment in which they are found. Therefore, data that provide context and enable interpretation of measurements produced from biological samples, often referred to as metadata, are critical. Important contributions have been made in the development of community-driven metadata standards; however, these standards have not been uniformly embraced by the microbiome research community. To understand how these standards are being adopted, or the barriers to adoption, across research domains, institutions, and funding agencies, the National Microbiome Data Collaborative (NMDC) hosted a workshop in October 2019. This report provides a summary of discussions that took place throughout the workshop, as well as outcomes of the working groups initiated at the workshop.

54 ENVIRONMENTAL SCIENCES↗

Limits on the production of the standard model Higgs boson in pp collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector

A search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7 TeV is reported, based on a total integrated luminosity of up to 40 pb -1 collected by the ATLAS detector in 2010. Several Higgs boson decay channels: H→γγ, H→ZZ (*) →ℓℓℓℓ, H→ZZ→ℓℓνν, H→ZZ→ℓℓqq, H→WW (*) →ℓνℓν and H→WW→ℓνqq (ℓ is e, μ) are combined in a mass range from 110 GeV to 600 GeV. The highest sensitivity is achieved in the mass range between 160 GeV and 170 GeV, where the expected 95% CL exclusion sensitivity is at Higgs boson production cross sections 2.3 times the Standard Model prediction. Upper limits on the cross section for its production are determined. Models with a fourth generation of heavy leptons and quarks with Standard Model-like couplings to the Higgs boson are also investigated and are excluded at 95% CL for a Higgs boson mass in the range from 140 GeV to 185 GeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗