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Search For The Standard Model Higgs Boson In The Missing Transverse Energy And B Jet Signature In Proton Antiproton Collisions At A Center Of Mass Energy Of 196 Tev
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Book Synopsis Search for the Standard Model Higgs Boson in the Missing Transverse Energy and B-jet Signature in Proton-antiproton Collisions at a Center-of-mass Energy of 1.96 TeV. by :
Download or read book Search for the Standard Model Higgs Boson in the Missing Transverse Energy and B-jet Signature in Proton-antiproton Collisions at a Center-of-mass Energy of 1.96 TeV. written by and published by . This book was released on 2009 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on the results of a search for the standard model Higgs boson produced in association with a W or Z boson in p{bar p} collisions at (square root)s = 1.96 TeV recorded by the CDF II experiment at the Tevatron in a data sample corresponding to an integrated luminosity of 2.1 fb−1. We consider events having no identified charged leptons, a large imbalance in transverse momentum, and two or three jets where at least one jet contains a secondary vertex consistent with the decay of a b hadron. The main backgrounds are modeled with innovative techniques using data. The sensitivity of the search is optimized using multivariate discriminant techniques. We find good agreement between data and the standard model predictions. We place 95% confidence level upper limits on production cross section times branching ratio for several Higgs boson masses ranging from 110 GeV=c2 to 150 GeV=c2. For a mass of 115 GeV=c2 the observed (expected) limit is 6.9 (5.6) times the standard model prediction.
Book Synopsis Search for the Standard Model Higgs Boson in Missing Transverse Energy and $b$-quark Final States Using Proton-Antiproton Collisions at 1.96 TeV. by :
Download or read book Search for the Standard Model Higgs Boson in Missing Transverse Energy and $b$-quark Final States Using Proton-Antiproton Collisions at 1.96 TeV. written by and published by . This book was released on 2011 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the standard model Higgs boson is performed in 6.4 fb−1 of p{bar p} collisions at √s = 1.96 TeV, collected with the D0 detector during Run II of the Fermilab Tevatron. The final state considered is a pair of jets originating from b quarks and missing transverse energy, as expected from p{bar p} → ZH → [nu]{bar [nu]}b{bar b} production. The search is also sensitive to the WH → l{nu}b{bar b} channel, where the charged lepton is not identified. Boosted decision trees are used to discriminate signal from background. Good agreement is observed between data and expected backgrounds, and a limit is set at 95% C.L. on the section multiplied by branching fraction of (p{bar p} → (Z/W)H) x (H → b{bar b}). For a Higgs boson mass of 115 GeV, the observed limit is a factor of 3.5 larger than the value expected from the standard model.
Book Synopsis Search for the Standard Model Higgs Boson in Missing Transverse Energy and B-quark Final States Using Proton-antiproton Collisions at 1.96 TeV by : Tyler McMillan Dorland
Download or read book Search for the Standard Model Higgs Boson in Missing Transverse Energy and B-quark Final States Using Proton-antiproton Collisions at 1.96 TeV written by Tyler McMillan Dorland and published by . This book was released on 2011 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for the Higgs Boson in Events with Missing Transverse Energy and B Quark Jets Produced in Proton-antiproton Collisions at S**1/2 by :
Download or read book Search for the Higgs Boson in Events with Missing Transverse Energy and B Quark Jets Produced in Proton-antiproton Collisions at S**1/2 written by and published by . This book was released on 2008 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We search for the standard model Higgs boson produced in association with an electroweak vector boson in events with no identified charged leptons, large imbalance in transverse momentum, and two jets where at least one contains a secondary vertex consistent with the decay of b hadrons. We use ≈1 fb−1 integrated luminosity of p{bar p} collisions at √s = 1.96 TeV recorded by the CDF II experiment at the Tevatron. We find 268 (16) single (double) b-tagged candidate events, where 248 ± 43 (14.4 ± 2.7) are expected from standard model background processes. We place 95% confidence level upper limits on the Higgs boson production cross section for several Higgs boson masses ranging from 110 GeV/c2 to 140 GeV/c2. For a mass of 115 GeV/c2 the observed (expected) limit is 20.4 (14.2) times the standard model prediction.
Book Synopsis Search for the Higgs Boson in Events with Missing Transverse Energy and B Quark Jets Produced in Proton-antiproton Collisions at S**ư by :
Download or read book Search for the Higgs Boson in Events with Missing Transverse Energy and B Quark Jets Produced in Proton-antiproton Collisions at S**ư written by and published by . This book was released on 2008 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We search for the standard model Higgs boson produced in association with an electroweak vector boson in events with no identified charged leptons, large imbalance in transverse momentum, and two jets where at least one contains a secondary vertex consistent with the decay of b hadrons. We use ≈1 fb−1 integrated luminosity of p{bar p} collisions at √s = 1.96 TeV recorded by the CDF II experiment at the Tevatron. We find 268 (16) single (double) b-tagged candidate events, where 248 ± 43 (14.4 ± 2.7) are expected from standard model background processes. We place 95% confidence level upper limits on the Higgs boson production cross section for several Higgs boson masses ranging from 110 GeV/c2 to 140 GeV/c2. For a mass of 115 GeV/c2 the observed (expected) limit is 20.4 (14.2) times the standard model prediction.
Book Synopsis Search for the Standard Model Higgs Boson in Proton-antiproton Collisions at a Center-of-mass Energy of 1.96 TeV. by :
Download or read book Search for the Standard Model Higgs Boson in Proton-antiproton Collisions at a Center-of-mass Energy of 1.96 TeV. written by and published by . This book was released on 2007 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: A scientifically accurate description of matter interpreted as a substance made up of corpuscular constituents was established during the course of the 19th century. In this description, atoms - the building blocks of the matter - form molecules. The properties of the molecules were described by chemistry or thermodynamics depending on what characteristics of the matter were investigated. In both theories, the molecules can dissociate to atoms when the kinetic energies of the atoms exceed the strength of the chemical bonds. The number of atoms is always preserved in a closed system. This is not true, however, when the matter takes up much higher energies at relativistic scales. New particles can be produced at the expense of the kinetic energy. The number of particles is no longer preserved. There are other conserved quantities, however, these quantities, the charge, baryon number, lepton number, are associated with particles that are considered elementary today. The properties and behavior of these elementary particles are the subject of Particle Physics or High Energy Physics.
Book Synopsis Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF. by :
Download or read book Search for Standard Model Higgs Boson Production in Association with a W Boson at CDF. written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a search for the standard model Higgs boson production in association with a $W$ boson in proton-antiproton collisions ($p\bar{p}\rightarrow W\̂pm H \rightarrow \ell\nu b\bar{b}$) at a center of mass energy of 1.96 TeV. The search employs data collected with the CDF II detector which correspond to an integrated luminosity of approximately 2.7 fb${̂-1}$. We recorded this data with two kinds of triggers. The first kind required high-p$_T$ charged leptons and the second required both missing transverse energy and jets. The search selects events consistent with a signature of a single lepton ($e\̂pm/\mu\̂pm$), missing transverse energy, and two jets. Jets corresponding to bottom quarks are identified with a secondary vertex tagging method and a jet probability tagging method. Kinematic information is fed in an artificial neural network to improve discrimination between signal and background. The search finds that both the observed number of events and the neural network output distributions are consistent with the standard model background expectations, and sets 95% confidence level upper limits on the production cross section times branching ratio. The limits are expressed as a ratio to the standard model production rate. The limits range from 3.6 (4.3 expected) to 61.1 (43.2 expected) for Higgs masses from 100 to 150 GeV/$c{̂2}$, respectively.
Book Synopsis Search for Higgs Boson Production in Proton-antiproton Collisions at {u221A}s by :
Download or read book Search for Higgs Boson Production in Proton-antiproton Collisions at {u221A}s written by and published by . This book was released on 2006 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: We performed a search for Standard Model Higgs boson production in association with W boson (p$ar{p}$ → W±H → lvb$ar{b}$) in p$ar{p}$ collisions at √s = 1.96 TeV. The search uses the data collected between February 2002 and February 2006 at Collider Detector at Fermilab (CDF), which corresponds to an integrated luminosity of about 1 fb-1. The experimental final state of WH → lvb$ar{b}$ process is lepton (e±/?±), missing transverse energy and two jets. The largest background in lepton+jets events is W+light flavor process, therefore the identification of jets as b-jets reduces this kind of background significantly. We used displaced SECondary VerTeX b-tagging (SECVTX) technique, which utilizes the signature that b-jets have secondary vertex displaced away from primary vertex because of the long life time of B-mesons. However, there is still much contamination in SECVTX b-tagged jets. Finite resolution of secondary vertex tracking measurements results in false tags, and c-jets are also identified as b-jets due to the long life time of D-mesons frequently. For the purpose of increasing the purity of the SECVTX b-tagged jets, we applied Neural Network to SECVTX tagged jets for the first time by using secondary vertex variables and some variables independent of it. Neural Network filter rejects 65% of light flavor jets and 50% of c-jets from the SECVTX tagged jets. We improved the sensitivity of the Higgs boson signal search by 10% with Neural Network b-tagging technique. Events with one high pT electron or muon, large missing transverse energy and either single SECVTX b-tagged jet which passes the Neural Network filter or at least two SECVTX b-tagged jets are selected. The number of selected events and dijet mass distributions are consistent with the Standard Model background expectations. Therefore we set an upper limit on ?(p$ar{p}$ → WH) • Br(H → b$ar{b}$) as 3.9 to 1.3 for Higgs boson mass from 110 to 150 GeV/c2 at 95% confidence level (C.L.). The upper limit obtained from WH → lvb$ar{b}$ process with 1 fb-1 is far away from the Standard Model Higgs boson production expectation by a factor of 20 to 100 as a function of Higgs boson mass. To obtain stronger constraint on the Higgs boson production, we combined the upper limits obtained in processes of ZH → ?$ar{v}$b$ar{b}$, ZH → l$ar{ℓ}$b$ar{b}$ and gg → H → W+W- → l$ar{ℓ}$v$ar{v}$ at CDF. The combination of different channels gives a constraint on the ratio of 95% confidence level upper limit divided by the Standard Model prediction ((? • Br)95/(? • Br)SM), which results in the ratio as 10 to 40 for Higgs boson mass between 110 and 200 GeV/c2. Finally, the combination of Higgs boson searches between CDF and D0 is also performed. The resulting constraint on (? • Br)95/(? • Br)SM is about 4 to 10 for Higgs boson mass between 110 and 200 GeV/c2.
Book Synopsis Search for the Higgs Boson Produced in Association with a W Boson at CDF Run II by : Jason Michael Slaunwhite
Download or read book Search for the Higgs Boson Produced in Association with a W Boson at CDF Run II written by Jason Michael Slaunwhite and published by . This book was released on 2009 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions at a center of mass energy of 1.96 TeV. WH candidate events have a signature of a single lepton, missing transverse energy, and two jets. The search looks for candidate events in approximately 2.7 fb−1 of data recorded with the CDF II detector. The high transverse momentum (high-pT) lepton (electron or muon) in the events provides a distinct signature for triggering and most of the events in the dataset come from high-pT lepton triggers. Our analysis improves on prior searches by including events recorded on the Missing Transverse Energy (MET) plus 2 jets trigger with a lepton reconstructed as an isolated high-pT charged particle. We increase the sample purity by identifying ("tagging") long-lived b-hadrons in jets. A neural network combines distinguishing kinematic information into a function optimized for WH sensitivity. The neural network output distributions are consistent with the standard model background expectations and we set limits upper limits on the rate of Higgs production. We set 95% confidence level upper limits on the WH production cross section times branching ratio for Higgs masses from 100 to 150 GeV/c2 and express our results as a ratio of the experimental limit to the theoretical Standard Model production rate. Our limits range from 3.6 (4.3 expected) to 61.1 (43.2 expected) for Higgs masses from 100 to 150 GeV/c2, respectively.
Book Synopsis Search for the Standard Model Higgs Boson in Associated Production with W Boson at the Tevatron by :
Download or read book Search for the Standard Model Higgs Boson in Associated Production with W Boson at the Tevatron written by and published by . This book was released on 2009 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the Standard Model Higgs boson in proton-antiproton collisions with center-of-mass energy 1.96 TeV at the Tevatron is presented in this dissertation. The process of interest is the associated production of W boson and Higgs boson, with the W boson decaying leptonically and the Higgs boson decaying into a pair of bottom quarks. The dataset in the analysis is accumulated by the D0 detector from April 2002 to April 2008 and corresponding to an integrated luminosity of 2.7 fb−1. The events are reconstructed and selected following the criteria of an isolated lepton, missing transverse energy and two jets. The D0 Neural Network b-jet identification algorithm is further used to discriminate b jets from light jets. A multivariate analysis combining Matrix Element and Neural Network methods is explored to improve the Higgs boson signal significance. No evidence of the Higgs boson is observed in this analysis. In consequence, an observed (expected) limit on the ratio of [sigma] (p{bar p} → WH) x Br (H → b{bar b}) to the Standard Model prediction is set to be 6.7 (6.4) at 95% C.L. for the Higgs boson with a mass of 115 GeV.
Book Synopsis Search for the Standard Model Higgs Boson in the H → ZZ → l + l - qq Decay Channel at CMS by : Francesco Pandolfi
Download or read book Search for the Standard Model Higgs Boson in the H → ZZ → l + l - qq Decay Channel at CMS written by Francesco Pandolfi and published by Springer Science & Business Media. This book was released on 2013-08-15 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theoretical foundations of the Standard Model of elementary particles relies on the existence of the Higgs boson, a particle which has been revealed for the first time by the experiments run at the Large Hadron Collider (LHC) in 2012. As the Higgs boson is an unstable particle, its search strategies were based on its decay products. In this thesis, Francesco Pandolfi conducted a search for the Higgs boson in the H → ZZ → l + l - qq Decay Channel with 4.6 fb -1 of 7 TeV proton-proton collision data collected by the Compact Muon Solenoid (CMS) experiment. The presence of jets in the final state poses a series of challenges to the experimenter: both from a technical point of view, as jets are complex objects and necessitate of ad-hoc reconstruction techniques, and from an analytical one, as backgrounds with jets are copious at hadron colliders, therefore analyses must obtain high degrees of background rejection in order to achieve competitive sensitivity. This is accomplished by following two directives: the use of an angular likelihood discriminant, capable of discriminating events likely to originate from the decay of a scalar boson from non-resonant backgrounds, and by using jet parton flavor tagging, selecting jets compatible with quark hadronization and discarding jets more likely to be initiated by gluons. The events passing the selection requirements in 4.6 fb -1 of data collected by the CMS detector are examined, in the search of a possible signal compatible with the decay of a heavy Higgs boson. The thesis describes the statistical tools and the results of this analysis. This work is a paradigm for studies of the Higgs boson with final states with jets. The non-expert physicists will enjoy a complete and eminently readable description of a proton-proton collider analysis. At the same time, the expert reader will learn the details of the searches done with jets at CMS.
Book Synopsis Search for the Standard Model Higgs Boson in the Z Boson-H Boson Decaying to Positive Muon-negative Muon and Bottom-anti-bottom Quark Channel in Proton-antiproton Collisions at the Center of Mass Energy by :
Download or read book Search for the Standard Model Higgs Boson in the Z Boson-H Boson Decaying to Positive Muon-negative Muon and Bottom-anti-bottom Quark Channel in Proton-antiproton Collisions at the Center of Mass Energy written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Search for the standard model Higgs boson in the Z boson-H boson decaying to positive muon-negative muon and bottom-anti-bottom quark channel in proton-antiproton collisions at the center of mass energy = 1.96 TeV.
Book Synopsis Search for a Standard Model Higgs Boson in the $\tau\tau$ Decay Channel Produced in $p\bar{p}$ Collisions at $\sqrt{s}$ by :
Download or read book Search for a Standard Model Higgs Boson in the $\tau\tau$ Decay Channel Produced in $p\bar{p}$ Collisions at $\sqrt{s}$ written by and published by . This book was released on 2011 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the search for the Standard Model Higgs boson decaying to tau lepton pairs, in the Tevatron proton-antiproton collisions at a center of mass energy $\sqrt{s}$ = 1.96 TeV. The search is based on approximately 2.3 fb$^{-1}$ of CDF Run II data and is performed by considering the following signal processes: WH($\rightarrow\tau\tau$), ZH($\rightarrow\tau\tau$), qHq'$\rightarrow$q$\tau\tau$q' and gg$\rightarrow$H$\rightarrow\tau\tau$. Events are selected by requiring an hadronic tau and one isolated electron or muon, coming from the leptonic decay of one of the two taus. In addition, at least one calorimeter jet must be present in the final state. We expect 921.8$\pm$48.9 background events in the 1 jet channel and 159.4$\pm$11.6 in the $\ge$ 2 jets channel, while in data we observe 965 and 166 events, respectively. In order to improve the search sensitivity we employ a multivariate technique, based on a set of Boosted Decision Trees trained to get the best sep aration between signal and the dominant sources of background. We observe no evidence for a Higgs boson signal and therefore we set a 95\% confidence level (C.L.) upper limit on the cross section relative to the SM predictions ($\sigma/\sigma_{\mathrm{SM}}$). Results are presented for the Higgs boson mass varying from M$_\mathrm{H}$ = 100 GeV/$c^2$ to M$_\mathrm{H}$ = 150 GeV/$c^2$. For the mass hypothesis of 120 GeV/c$^2$ the observed limit is 27.2, while the corresponding expected value is 23.4$^{+9.8}_{-6.4}$.
Download or read book การผลิตโซเดียมคลอไรด์ written by and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for the Standard Model Higgs Boson Produced in Association with a W Boson in the Isolated-track Charged-lepton Channel Using the Collider Detector at Fermilab by :
Download or read book Search for the Standard Model Higgs Boson Produced in Association with a W Boson in the Isolated-track Charged-lepton Channel Using the Collider Detector at Fermilab written by and published by . This book was released on 2011 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Higgs boson is the only elementary particle predicted by the Standard Model (SM) that has not yet been observed experimentally. If it exists, it explains the spontaneous electroweak symmetry breaking and the origin of mass for gauge bosons and fermions. We test the validity of the SM by performing a search for the associated production of a Higgs boson and a W boson in the channel where the Higgs boson decays to a bottom-antibottom quark pair and the W boson decays to a charged lepton and a neutrino (the WH channel). We study a dataset of proton-antiproton collisions at a centre-of-mass energy √s = 1.96 TeV provided by the Tevatron accelerator, corresponding to an integrated luminosity of 5.7 fb−1, and recorded using the Collider Detector at Fermilab (CDF).We select events consistent with the signature of exactly one charged lepton (electron or muon), missing transverse energy due to the undetected neutrino (MET) and two collimated streams of particles (jets), at least one of which is required to be identified as originating from a bottom quark. We improve the discrimination of Higgs signal from backgrounds through the use of an artificial neural network. Using a Bayesian statistical inference approach, we set for each hypothetical Higgs boson mass in the range 100-150 GeV/c2 with 5 GeV/c2 increments a 95% credibility level (CL) upper limit on the ratio between the Higgs production cross section times branching fraction and the SM prediction. Our main original contributions are the addition of a novel charged lepton reconstruction algorithm with looser requirements (ISOTRK) with respect the electron or muon tight criteria (TIGHT), as well as the introduction of a novel trigger-combination method that allows to maximize the event yield while avoiding trigger correlations and that is used for the ISOTRK category. The ISOTRK candidate is a high-transverse-momentum good-quality track isolated from other activity in the tracking system and not required to match a calorimeter cluster, as for a tight electron candidate, or an energy deposit in the muon detector, as for a tight muon candidate. The ISOTRK category recovers real charged leptons that otherwise would be lost in the non-instrumented regions of the detector. This allows the reconstruction of more W boson candidates, which in turn increases the number of reconstructed WH signal candidate events, and therefore improves the sensitivity of the WH search. For the TIGHT charged lepton categories, we employ charged-lepton-dedicated triggers to improve the rate of WH signal acceptance during data taking. Since there is no ISOTRK-dedicated trigger at CDF, for the ISOTRK charged lepton category we employ three MET-plus-jets-based triggers. For each trigger we first identify the jet selection where the trigger efficiency is flat with respect to jet information (transverse energy and direction of motion in the transverse plane for the two jets in the event) and then we parametrize the trigger efficiency as a function of trigger MET. On an event-by-event basis, for each trigger we compute a trigger efficiency as a function of trigger parametrization, trigger MET, jet information, trigger prescale and information about whether the trigger is defined or not. For the ISOTRK category we combine the three triggers using a novel method, which allows the combination of any number of triggers in order to maximize the event yield while avoiding trigger correlations. On an event-by-event basis, only the trigger with the largest efficiency is used. By avoiding a logical 'OR' between triggers, the loss in the yield of events accepted by the trigger combination is compensated by a smaller and easier-to-compute corresponding systematic uncertainty. The addition of the ISOTRK charged lepton category to the TIGHT category produces an increase of 33% in the WH signal yield and a decrease of 15.5% to 19.0% in the median expected 95% CL cross-section upper limits across the entire studied Higgs mass interval. The improvement in analysis sensitivity is smaller than the improvement in signal yield because the ISOTRK category has a smaller signal over background ratio than the TIGHT category, due to the looser ISOTRK reconstruction criteria. The observed (median expected) 95% CL SM Higgs upper limits on cross section times branching ratio vary between 2.39 x SM (2.73 x SM) for a Higgs mass of 100 GeV/c2 to 31.1 x SM (31.2 x SM) for a Higgs mass of 150 GeV/c2, while the value for a 115 GeV/c2 Higgs boson is that of 5.08 x SM (3.79 x SM). The novel trigger combination method is already in use by several CDF analyses. It is applicable to any analysis that uses triggers based on MET and jets, such as supersymmetry searches at the ATLAS and CMS experiments at the Large Hadron Collider. In its most general form, the method can be used by any analysis that combines any number of different triggers.
Book Synopsis A Search for the Standard Model Higgs Boson with Missing Mass Final States at Center-of-mass Energy at 188.6 GeV with the ALEPH Detector at LEP by : Xidong Wu
Download or read book A Search for the Standard Model Higgs Boson with Missing Mass Final States at Center-of-mass Energy at 188.6 GeV with the ALEPH Detector at LEP written by Xidong Wu and published by . This book was released on 2000 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Search for the Standard Model Higgs Boson in ZH {u2192} V$\bar{v}$b$\bar{b}$ Channel in P$\bar{p}$ Collisions at {u221A}s by :
Download or read book Search for the Standard Model Higgs Boson in ZH {u2192} V$\bar{v}$b$\bar{b}$ Channel in P$\bar{p}$ Collisions at {u221A}s written by and published by . This book was released on 2011 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the standard model Higgs boson is performed in 5.2 fb-1 of p$ar{p}$ collisions at p √s = 1.96 TeV, collected with the DØ detector at the Fermilab Tevatron. The final state considered is a pair of b jets with large missing transverse energy, as expected from p$ar{p}$→ ZH → v$ar{v}$b$ar{b}$ production. The search is also sensitive to the WH → lvb$ar{b}$ channel, where the charged lepton is not identified. Boosted decision trees are used to discriminate signal from background. Good agreement is observed between data and expected backgrounds, and, for a Higgs-boson mass of 115 GeV, a limit is set at 95% C.L. on the cross section multiplied by branching fraction of (p$ar{p}$ → (Z/W)H) × (H → b$ar{b}$) that is a factor 4.57 expected and 3.73 observed larger than the value expected from the standard model.
