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Some Comments on the La Primavera Geothermal Field, Mexico

Description: The La Primavera geothermal field is located about 20 km west of the city of Guadalajara, Jalisco, in the western part of the Mexican Neovolcanic Axis. Initial results of five deep exploration wells (down to 2000 m depth) were very promising; measured downhole temperatures exceed 300/sup 0/C. During production, however, downhole temperatures dropped, and the chemistry of the fluids changed. The analysis of geologic, mineralogic, geochemical, and well completion data indicate that colder fluids flow down the wellbore from shallower aquifers cooling the upper zones of the geothermal reservoir. This problem is attributed to inadequate well completions. Doubts have arisen about continuing the exploration of the field because of the somewhat disappointing drilling results. However, a more thorough analysis of all available data indicates that a good geothermal prospect might exist below 3000 m, and that it could be successfully developed with appropriately located and completed wells.
Date: December 1, 1983
Creator: A., B. Dominguez & Lippmann, M. J.
Partner: UNT Libraries Government Documents Department
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Mexican-American Cooperative Program at the Cerro Prieto Geothermal Field: Recent Results of the Well-Drilling Program at Cerro Prieto

Description: The results of the 1980 and 1981 well drilling activities at the Cerro Prieto geothermal field are summarized. Details are given on the new series of deeper wells completed in the western (older) part of the field (Cerro Prieto I), and on the development and step-out wells drilled in the eastern part of the field (Cerro Prieto II and III). Production characteristics of on-line and standby wells are discussed. Recent changes in well completion procedures are also described.
Date: December 1, 1981
Creator: A., B. Dominguez; Lippmann, M. J. & M., Francisco Bermejo
Partner: UNT Libraries Government Documents Department
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Editing Tips for Technical Publications in the Joint Nuclear Weapons Publication System (JNWPS)

Description: These editing tips contain helpful suggestions to assist writers who are writing, editing, and publishing technical publications in the JNWPS. The suggestions clarify some of the most common writing problems and requirements of two publications used in the JNWPS: ''DOE-DTRA TP 1-1, Joint Nuclear Weapons Publications System Operating Procedures, Specifications, and Standards, and United States Government Printing Office Style Manual''. Topics include requirements for abbreviations, formats for drafts, layouts of illustrations and tables, appropriate wording for interim changes, guidance for creating a list of effective pages, how to insert and delete pages and paragraphs, referencing other technical publications, use of revision bars, requirements for safety precautions, use of hyphens, and how to place warnings, cautions, and notes. Also included are a writer's checklist, samples of draft title pages, and a section of helpful tips for the writers who use the department's desktop publishing software program, Adobe{reg_sign} FrameMaker{reg_sign}.
Date: December 1, 2002
Creator: ALLEN, TARA S.
Partner: UNT Libraries Government Documents Department
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Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

Description: Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be integrated with either gas or liquid-phase chem-lab-on-a-chip separation columns to provide a highly sensitive, highly selective microanalytical system for detecting current and future chem/bio agents. In addition, improved protein microchromatographic systems have been made by the creation of acrylate-based porous polymer monoliths that can serve as protein preconcentrators to reduce the optical system sensitivity required to detect and identify a particular protein, such as a bacterial toxin.
Date: December 1, 2002
Creator: ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G. & MURON, DAVID J.
Partner: UNT Libraries Government Documents Department
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DISPERSION ANALYSIS OF RADIATION/THERMAL FRONTS WITH FULL RESOLVED SPECTRAL OPACITY VARIATION.

Description: The radiation transport and linearized thermal energy equations have been analyzed to find the temporal dependence of the component modes in a radiation/thermal front. The fully resolved spectral variation of the opacity as a function of energy, as well as the exact time and angular dependence, is treated in this work. As we are able to study arbitrarily complicated opacity spectra, we stress the importance of the new results as a check on the effect of using opacity averages.
Date: December 1, 2000
Creator: AUER, L. & LOWRIE, R.
Partner: UNT Libraries Government Documents Department
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Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

Description: A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Partner: UNT Libraries Government Documents Department
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Classification of hydrostratigraphic units at the Savannah River Site, South Carolina

Description: A detailed synthesis of the hydrologic, geophysical and core data from wells penetrating the updip Mesozoic-Cenozoic Coastal Plain sequence at and near the Savannah River Site (SRS) was conducted to define and classify the hydrostratigraphic units. The purpose of the study was to give the SRS a single unified hydrostratigraphic classification that defines and addresses the hydrogeologic characteristics of the aquifers underlying the site. The characterization, areal distribution and classification of the aquifer and aquifer systems gives SRS the tools to evaluate ground water movement and contaminant transport in a comprehensive regional context. An alpha-numeric nomenclature has been temporarily adopted in this report for classifying the aquifers and aquifer systems at SRS. Formal geographic names for the aquifers and aquifer systems will be proposed in the near future but must be agreed upon and ratified by the South Carolina Hydrostratigraphic Subcommittee which was in part organized for the purpose. The classification utilizes a hierarchy of terms ranked at three levels: Aquifer Systems that transmit ground water regionally; Aquifer Units which are mappable units > 400 square miles in area; and Aquifer Zones that differentiate aquifers internally on the basis of locally significant characteristics.
Date: December 1, 1990
Creator: Aadland, R. K. & Bledsoe, H. W.
Partner: UNT Libraries Government Documents Department
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Measurement of Lifetime and Decay-Width Difference in B0s -> J/psi phi Decays

Description: The authors measure the mean lifetime, {tau} = 2/({Lambda}{sub L} + {Lambda}{sub H}), and the decay-width difference, {Delta}{Lambda} = {Lambda}{sub L} - {Lambda}{sub H}, of the light and heavy mass eigenstates of the B{sub s}{sup 0} meson, B{sub sL}{sup 0} and B{sub sH}{sup 0}, in B{sub s}{sup 0} {yields} J/{psi}{phi} decays using 1.7 fb{sup -1} of data collected with the CDF II detector at the Fermilab Tevatron p{bar p} collider. Assuming CP conservation, a good approximation for the B{sub s}{sup 0} system in the standard model, they obtain {Delta}{Lambda} = 0.076{sub -0.063}{sup +0.059}(stat.) {+-} 0.006(syst.) ps{sup -1} and {tau} = 1.52 {+-} 0.04(stat.) {+-} 0.02(syst.) ps, the most precise measurements to date. The constraints on the weak phase and {Delta}{Lambda} are consistent with CP conservation.
Date: December 1, 2007
Creator: Aaltonen, : T.
Partner: UNT Libraries Government Documents Department
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Observation of the Decay B+-(c) ---> J/psi pi+- and Measurement of the B+-(c) Mass

Description: The B{sub c}{sup {+-}} meson is observed through the decay B{sub c}{sup {+-}} {yields} J/{psi} {pi}{sup {+-}}, in data corresponding to an integrated luminosity of 2.4 fb{sup -1} recorded by the CDF II detector at the Fermilab Tevatron. A signal of 108 {+-} 15 candidates is observed, with a significance that exceeds 8{sigma}. The mass of the B{sub c}{sup {+-}} meson is measured to be 6275.6 {+-} 2.9(stat.) {+-} 2.5(syst.) MeV/c{sup 2}.
Date: December 1, 2007
Creator: Aaltonen, T.
Partner: UNT Libraries Government Documents Department
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Search for doubly charged Higgs bosons with lepton-flavour-violating decays involving tau leptons

Description: The authors search for pair production of doubly charged Higgs particles (H{sup {+-}{+-}}) followed by decays into electron-tau (e{tau}) and muon-tau ({mu}{tau}) pairs using a data set corresponding to an integrated luminosity of 350 pb{sup -1} collected from {bar p}p collisions at {radical}s = 1.96 TeV by the CDF II experiment. They search separately for cases where three or four final-state leptons are detected, and then combine the results into limits for each exclusive flavor decay mode of the H{sup {+-}{+-}}. Assuming 100% branching ratios of the H{sup {+-}{+-}} to left-handed e{tau} ({mu}{tau}) pairs, they set an H{sup {+-}{+-}} lower mass limit of 114 (112) GeV/c{sup 2} at the 95% confidence level (C.L.).
Date: December 1, 2007
Creator: Aaltonen, T.
Partner: UNT Libraries Government Documents Department
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Measurement of the top-quark mass in all-hadronic decays in p anti-p collisions at CDF II

Description: We present a measurement of the top-quark mass, M{sub tpo}, in the all-hadronic decay channel t{bar t} {yields} W{sup +}bW{sup -}{bar b} {yields} q{sub 1}{bar q}{sub 2}bq{sub 3}{bar q}{sub 4}{bar b}. The analysis is performed using 310 pb{sup -1} of {radical}s = 1.96 TeV p{bar p} collisions collected with the CDF II detector using a multi-jet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value of M{sub top} = 177.1 {+-} 4.9(stat.) {+-} 4.7(syst.) GeV/c{sup 2}.
Date: December 1, 2006
Creator: Aaltonen, T.; Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G. et al.
Partner: UNT Libraries Government Documents Department
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Observation of Exclusive Dijet Production at the Fermilab Tevatron p-pbar Collider

Description: The authors present the first observation and cross section measurement of exclusive dijet production in {bar p}p interactions, {bar p}p {yields} {bar p} + dijet + p. Using a data sample of 310 pb{sup -1} collected by the Run II Collider Detector at Fermilab at {radical}s = 1.96 TeV, exclusive cross sections for events with two jets of transverse energy E{sub T}{sup jet} {ge} 10 GeV have been measured as a function of minimum E{sub T}{sup jet}. The exclusive signal is extracted from fits to data distributions based on Monte Carlo simulations of expected dijet signal and background shapes. The simulated background distribution shapes are checked in a study of a largely independent data sample of 200 pb{sup -1} of b-tagged jet events, where exclusive dijet production is expected to be suppressed by the J{sub z} = 0 total angular momentum selection rule. Results obtained are compared with theoretical expectations, and implications for exclusive Higgs boson production at the pp Large Hadron Collider at {radical}s = 14 TeV are discussed.
Date: December 1, 2007
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Albrow, M. G.; Gonzalez, B.Alvarez; Amerio, S. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of Cross Sections for b Jet Production in Events with a Z Boson in p-anti-p Collisions at s**(1/2) = 1.96-TeV

Description: A measurement of the b jet production cross section is presented for events containing a Z boson produced in p{bar p} collisions at {radical}s = 1.96 TeV, using data corresponding to an integrated luminosity of 2 fb{sup -1} collected by the CDF II detector at the Tevatron. Z bosons are selected in the electron and muon decay modes. Jets are considered with transverse energy E{sub T} > 20 GeV and pseudorapidity |{eta}| < 1.5 and are identified as b jets using a secondary vertex algorithm. The ratio of the integrated Z+b jet cross section to the inclusive Z production cross section is measured to be 3.32 {+-} 0.53(stat:) {+-} 0.42(syst:) x 10{sup -3}. This ratio is also measured differentially in jet E{sub T}, jet {eta}, Z-boson transverse momentum, number of jets, and number of b jets. The predictions from leading order Monte Carlo generators and next-to-leading-order QCD calculations are found to be consistent with the measurements within experimental and theoretical uncertainties.
Date: December 1, 2008
Creator: Aaltonen, T.; Adelman, J.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of the Lambda_b Lifetime in Lambda_b -> Lambda_c+ pi- Decays in p-pbar Collisions at sqrt(s) = 1.96 TeV

Description: We report a measurement of the lifetime of the {Lambda}{sub b}{sup 0} baryon in decays to the {Lambda}{sub c}{sup +} {pi}{sup -} final state in a sample corresponding to 1.1 fb{sup -1} collected in p{bar p} collisions at {radical}s = 1.96 TeV by the CDF II detector at the Tevatron collider. Using a sample of about 3000 fully reconstructed {Lambda}{sub b}{sup 0} events we measure {tau}({Lambda}{sub b}{sup 0}) = 1.401 {+-} 0.046 (stat) {+-} 0.035 (syst) ps (corresponding to c{tau}({Lambda}{sub b}{sup 0}) = 420.1 {+-} 13.7 (stat) {+-} 10.6 (syst) {micro}m, where c is the speed of light). The ratio of this result and the world average B{sup 0} lifetime yields {tau}({Lambda}{sub b}{sup 0})/{tau}(B{sup 0}) = 0.918 {+-} 0.038 (stat and syst), in good agreement with recent theoretical predictions.
Date: December 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Partner: UNT Libraries Government Documents Department
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Search for Technicolor Particles Produced in Association with a W Boson at CDF

Description: We present a search for the technicolor particles {rho}{sub T} and {pi}{sub T} in the process p{bar p} {yields} {rho}{sub T} {yields} W{pi}{sub T} at a center of mass energy of {radical}s = 1.96 TeV. The search uses a data sample corresponding to approximately 1.9 fb{sup -1} of integrated luminosity accumulated by the CDF II detector at the Fermilab Tevatron. The event signature we consider is W {yields} {ell}{nu} and {pi}{sub T} {yields} b{bar b}, b{bar c} or b{bar u} depending on the {pi}{sub T} charge. We select events with a single high-p{sub T} electron or muon, large missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with multiple b-tagging algorithms. The observed number of events and the invariant mass distributions are consistent with the standard model background expectations, and we exclude a region at 95% confidence level in the {rho}{sub T}-{pi}{sub T} mass plane. As a result, a large fraction of the region m({rho}{sub T}) = 180-250 GeV/c{sup 2} and m({pi}{sub T}) = 95-145 GeV/c{sup 2} is excluded.
Date: December 1, 2009
Creator: Aaltonen, T.; Adelman, J.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Partner: UNT Libraries Government Documents Department
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Observation of Exclusive Gamma Gamma Production in $p \bar{p}$ Collisions at $\sqrt{s}=1.96$ TeV

Description: We have observed exclusive {gamma} production in proton-antiproton collisions at {radical}s = 1.96 TeV, using data from 1.11 {+-} 0.07 fb{sup -1} integrated luminosity taken by the Run II Collider Detector at Fermilab. We selected events with two electromagnetic showers, each with transverse energy E{sub T} > 2.5 GeV and pseudorapidity |{eta}| < 1.0, with no other particles detected in -7.4 < {eta} < +7.4. The two showers have similar E{sub T} and azimuthal angle separation {Delta}{phi} {approx} {pi}; 34 events have two charged particle tracks, consistent with the QED process p{bar p} {yields} p + e{sup +}e{sup -} + {bar p} by two-photon exchange, while 43 events have no charged tracks. The number of these events that are exclusive {pi}{sup 0}{pi}{sup 0} is consistent with zero and is < 15 at 95% C.L. The cross section for p{bar p} {yields} p + {gamma}{gamma} + {bar p} with |{eta}({gamma})| < 1.0 and E{sub T} ({gamma}) > 2.5 GeV is 2.48{sub -0.35}{sup +0.40}(stat){sub -0.51}{sup +0.40}(syst)pb.
Date: December 1, 2011
Creator: Aaltonen, T.; Albrow, M. G.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of the branching fraction ${\mathcal{B}}(\Lambda^0_b\rightarrow \Lambda^+_c\pi^-\pi^+\pi^-)$ at CDF

Description: We report an analysis of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay in a data sample collected by the CDF II detector at the Fermilab Tevatron corresponding to 2.4 fb{sup -1} of integrated luminosity. We reconstruct the currently largest samples of the decay modes {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2595){sup +}{pi}{sup -} (with {Lambda}{sub c}(2595){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}(2625){sup +}{pi}{sup -} (with {Lambda}{sub c}(2625){sup +} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}{pi}{sup -}), {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455){sup ++}{pi}{sup -}{pi}{sup -} (with {Sigma}{sub c}(2455){sup ++} {yields} {Lambda}{sub c}{sup +}{pi}{sup +}), and {Lambda}{sub b}{sup 0} {yields} {Sigma}{sub c}(2455)0{pi}{sup +}{pi}{sup -} (with {Sigma}{sub c}(2455)0 {yields} {Lambda}{sub c}{sup +}{pi}{sup -}) and measure the branching fractions relative to the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} branching fraction. We measure the ratio {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})/ {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -})=3.04 {+-} 0.33(stat){sub -0.55}{sup +0.70}(syst) which is used to derive {Beta}({Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -})=(26.8{sub -11.2}{sup +11.9}) x 10{sup -3}.
Date: December 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of the Top Quark Mass in the All-Hadronic Mode at CDF

Description: A measurement of the top quark mass (M{sub top}) in the all-hadronic decay channel is presented. It uses 5.8 fb{sup -1} of p{bar p} data collected with the CDF II detector at the Fermilab Tevatron Collider. Events with six to eight jets are selected by a neural network algorithm and by the requirement that at least one of the jets is tagged as a b quark jet. The measurement is performed with a likelihood fit technique, which simultaneously determines M{sub top} and the jet energy scale (JES) calibration. The fit yields a value of M{sub top} = 172.5 {+-} 1.4 (stat) {+-} 1.0 (JES) {+-} 1.1 (syst) GeV/c{sup 2}.
Date: December 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of $ZZ$ production in leptonic final states at $\surd{s}$ of 1.96 TeV at CDF

Description: In this paper we present a precise measurement of the total ZZ production cross section in p{bar p} collisions at {radical}s = 1.96 TeV, using data collected with the CDF II detector corresponding to an integrated luminosity of approximately 6 fb{sup -1}. The result is obtained by combining separate measurements in the four-charged ({ell}{ell}{ell}{prime}{ell}{prime}), and two-charged-lepton and two-neutral-lepton ({ell}{ell}{nu}{nu}) decay modes of the Z. The combined measured cross section for p{bar p} {yields} ZZ is 1.64{sub -0.38}{sup +0.44} pb. This is the most precise measurement of the ZZ production cross section in 1.96 TeV p{bar p} collisions to date.
Date: December 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
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Search for Standard Model Higgs Boson Production in Association with a $W$ Boson Using a Matrix Element Technique at CDF in $p\bar{p}$ Collisions at $\sqrt{s} = 1.96$ TeV

Description: 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 dataset corresponding to an integrated luminosity of 5.6 fb{sup -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 {sigma}(p{bar p} {yields} WH) x {Beta}(H {yields} b{bar b}). The observed limits range from 3.5 to 37.6 relative to the standard model expectation for Higgs boson masses between m{sub H} = 100 GeV/c{sup 2} and m{sub H} = 150 GeV/c{sup 2}. 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.
Date: December 1, 2011
Creator: Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A. et al.
Partner: UNT Libraries Government Documents Department
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