LARGE-SCALE DISTRIBUTION OF ARRIVAL DIRECTIONS OF COSMIC RAYS DETECTED ABOVE 10(18) eV AT THE PIERRE AUGER OBSERVATORY

A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10(18) eV at the Pierre Auger Observatory is presented. This search is performed as a function of both declination and right ascension in several energy ranges above 10(18) eV, and reported in terms of dipolar and quadrupolar coefficients. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Assuming that any cosmic-ray anisotropy is dominated by dipole and quadrupole moments in this energy range, upper limits on their amplitudes are derived. These upper limits allow us to test the origin of cosmic rays above 10(18) eV from stationary Galactic sources densely distributed in the Galactic disk and predominantly emitting light particles in all directions.

J/psi Suppression at Forward Rapidity in Pb-Pb Collisions at root s(NN)=2.76 TeV

The ALICE experiment has measured the inclusive J/psi production in Pb-Pb collisions at root s(NN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/psi yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545 +/- 0.032(stat) +/- 0.083dsyst_ and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/psi production from charm quarks in a deconfined partonic phase can describe our data.

CP asymmetries in the supersymmetric trilepton signal at the LHC

In the CP-violating Minimal Supersymmetric Standard Model, we study the production of a neutralino-chargino pair at the LHC. For their decays into three leptons, we analyze CP asymmetries which are sensitive to the CP phases of the neutralino and chargino sector. We present analytical formulas for the entire production and decay process, and identify the CP-violating contributions in the spin correlation terms. This allows us to define the optimal CP asymmetries. We present a detailed numerical analysis of the cross sections, branching ratios, and the CP observables. For light neutralinos, charginos, and squarks, the asymmetries can reach several 10%. We estimate the discovery potential for the LHC to observe CP violation in the trilepton channel.

Evaluation of gamma-radiation on oolong tea odor volatiles

The aim of this study was to evaluate the gamma radiation effects on odor volatiles in oolong tea at doses of 0, 5, 10, 15 and 20 kGy. The volatile organic compounds were extracted by hydrodistillation and analyzed by GC/MS. The irradiation has a large influence on oolong tea odor profile, once it was identified 40% of new compounds after this process, the 5 kGy and 20 kGy were the doses that degraded more volatiles found naturally in this kind of tea and the dose of 10 kGy was the dose that formed more new compounds. Statistical difference was found between the 5 kGy and 15 kGy volatile profiles, however the sensorial analysis showed that the irradiation at dose up 20 kGy did not interfere on consumer perception. (C) 2011 Elsevier Ltd. All rights reserved.

Exploring nu signals in dark matter detectors

We investigate standard and non-standard solar neutrino signals in direct dark matter detection experiments. It is well known that even without new physics, scattering of solar neutrinos on nuclei or electrons is an irreducible background for direct dark matter searches, once these experiments reach the ton scale. Here, we entertain the possibility that neutrino interactions are enhanced by new physics, such as new light force carriers (for instance a "dark photon") or neutrino magnetic moments. We consider models with only the three standard neutrino flavors, as well as scenarios with extra sterile neutrinos. We find that low-energy neutrino-electron and neutrino-nucleus scattering rates can be enhanced by several orders of magnitude, potentially enough to explain the event excesses observed in CoGeNT and CRESST. We also investigate temporal modulation in these neutrino signals, which can arise from geometric effects, oscillation physics, non-standard neutrino energy loss, and direction-dependent detection efficiencies. We emphasize that, in addition to providing potential explanations for existing signals, models featuring new physics in the neutrino sector can also be very relevant to future dark matter searches, where, on the one hand, they can be probed and constrained, but on the other hand, their signatures could also be confused with dark matter signals.

Retinal cell death induced by TRPV1 activation involves NMDA signaling and upregulation of nitric oxide synthases

The activation of the transient receptor potential vanilloid type 1 channel (TRPV1) has been correlated with oxidative and nitrosative stress and cell death in the nervous system. Our previous results indicate that TRPV1 activation in the adult retina can lead to constitutive and inducible nitric oxide synthase-dependent protein nitration and apoptosis. In this report, we have investigated the potential effects of TRPV1 channel activation on nitric oxide synthase (NOS) expression and function, and the putative participation of ionotropic glutamate receptors in retinal TRPV1-induced protein nitration, lipid peroxidation, and DNA fragmentation. Intravitreal injections of the classical TRPV1 agonist capsaicin up-regulated the protein expression of the inducible and endothelial NOS isoforms. Using 4,5-diaminofluorescein diacetate for nitric oxide (NO) imaging, we found that capsaicin also increased the production of NO in retinal blood vessels. Processes and perikarya of TRPV1-expressing neurons in the inner nuclear layer of the retina were found in the vicinity of nNOS-positive neurons, but those two proteins did not colocalize. Retinal explants exposed to capsaicin presented high protein nitration, lipid peroxidation, and cell death, which were observed in the inner nuclear and plexiform layers and in ganglion cells. This effect was partially blocked by AP-5, a NMDA glutamate receptor antagonist, but not by CNQX, an AMPA/kainate receptor antagonist. These data support a potential role for TRPV1 channels in physiopathological retinal processes mediated by NO, which at least in part involve glutamate release.

Resonant States in Negative Ions

Resonant states are multiply excited states in atoms and ions that have enough energy to decay by emitting an electron. The ability to emit an electron and the strong electron correlation (which is extra strong in negative ions) makes these states both interesting and challenging from a theoretical point of view. The main contribution in this thesis is a method, which combines the use of B splines and complex rotation, to solve the three-electron Schrödinger equation treating all three electrons equally. It is used to calculate doubly excited and triply excited states of 4S symmetry with even parity in He-. For the doubly excited states there are experimental and theoretical data to compare with. For the triply excited states there is only theoretical data available and only for one of the resonances. The agreement is in general good. For the triply excited state there is a significant and interesting difference in the width between our calculation and another method. A cause for this deviation is suggested. The method is also used to find a resonant state of 4S symmetry with odd parity in H2-. This state, in this extremely negative system, has been predicted by two earlier calculations but is highly controversial. Several other studies presented here focus on two-electron systems. In one, the effect of the splitting of the degenerate H(n=2) thresholds in H-, on the resonant states converging to this threshold, is studied. If a completely degenerate threshold is assumed an infinite series of states is expected to converge to the threshold. Here states of 1P symmetry and odd parity are examined, and it is found that the relativistic and radiative splitting of the threshold causes the series to end after only three resonant states. Since the independent particle model completely fails for doubly excited states, several schemes of alternative quantum numbers have been suggested. We investigate the so called DESB (Doubly Excited Symmetry Basis) quantum numbers in several calculations. For the doubly excited states of He- mentioned above we investigate one resonance and find that it cannot be assigned DESB quantum numbers unambiguously. We also investigate these quantum numbers for states of 1S even parity in He. We find two types of mixing of DESB states in the doubly excited states calculated. We also show that the amount of mixing of DESB quantum numbers can be inferred from the value of the cosine of the inter-electronic angle. In a study on Li- the calculated cosine values are used to identify doubly excited states measured in a photodetachment experiment. In particular a resonant state that violates a propensity rule is found.

Serch for Neutralino Dark Matter with the AMANDA-II Neutrino Telescope

The annihilation of weakly interacting massive particles (WIMPs), accumulated in gravitational potentials (e.g., the core of the Earth, the Sun or the Galactic halo) would lead to neutrino production. This thesis investigates the possibility of searching for WIMPs in the form of the lightest supersymmetric particle (neutralino) trapped in the Sun using the AMANDA-II neutrino telescope. AMANDA-II is a large Cherenkov detector located deep in the ice at the geographical South Pole. The presented work is based on data taken during the year 2001. An analysis optimized to search for the neutralino-induced flux from the Sun has been developed. The observation of no excess with respect to the expected atmospheric neutrino background has been interpreted as an upper limit on the neutralino annihilation rate in the Sun and on the neutralino-induced muon flux in the vicinity of the detector.

A Dark Matter Search with AMANDA : Limits on the Muon Flux from Neutralino Annihilations at the Centre of the Earth with 1997-99 Data

The nature of the dark matter in the Universe is one of the greatest mysteries in modern astronomy. The neutralino is a nonbaryonic dark matter candidate in minimal supersymmetric extensions to the standard model of particle physics. If the dark matter halo of our galaxy is made up of neutralinos some would become gravitationally trapped inside massive bodies like the Earth. Their pair-wise annihilation produces neutrinos that can be detected by neutrino experiments looking in the direction of the centre of the Earth. The AMANDA neutrino telescope, currently the largest in the world, consists of an array of light detectors buried deep in the Antarctic glacier at the geographical South Pole. The extremely transparent ice acts as a Cherenkov medium for muons passing the array and using the timing information of detected photons it is possible to reconstruct the muon direction. A search has been performed for nearly vertically upgoing neutrino induced muons with AMANDA-B10 data taken over the three year period 1997-99. No excess above the atmospheric neutrino background expectation was found. Upper limits at the 90 % confidence level has been set on the annihilation rate of neutralinos at the centre of the Earth and on the muon flux induced by neutrinos created by the annihilation products.

Supersymmetric Dark Matter : aspects of sfermion coannihilations

There is very strong evidence that ordinary matter in the Universe is outweighed by almost ten times as much so-called dark matter. Dark matter does neither emit nor absorb light and we do not know what it is. One of the theoretically favoured candidates is a so-called neutralino from the supersymmetric extension of the Standard Model of particle physics. A theoretical calculation of the expected cosmic neutralino density must include the so-called coannihilations. Coannihilations are particle processes in the early Universe with any two supersymmetric particles in the initial state and any two Standard Model particles in the final state. In this thesis we discuss the importance of these processes for the calculation of the relic density. We will go through some details in the calculation of coannihilations with one or two so-called sfermions in the initial state. This includes a discussion of Feynman diagrams with clashing arrows, a calculation of colour factors and a discussion of ghosts in non-Abelian field theory. Supersymmetric models contain a large number of free parameters on which the masses and couplings depend. The requirement, that the predicted density of cosmic neutralinos must agree with the density observed for the unknown dark matter, will constrain the parameters. Other constraints come from experiments which are not related to cosmology. For instance, the supersymmetric loop contribution to the rare b -> sγ decay should agree with the measured branching fraction. The principles of the calculation of the rare decay are discussed in this thesis. Also on-going and planned searches for cosmic neutralinos can constrain the parameters. In one of the accompanying papers in the thesis we compare the detection prospects for several current and future searches for neutralino dark matter.

Catalytic liquid- and gas-phase oxidations for the synthesis of intermediates and specialty chemicals: some examples of industrial relevance

Nowadays, it is clear that the target of creating a sustainable future for the next generations requires to re-think the industrial application of chemistry. It is also evident that more sustainable chemical processes may be economically convenient, in comparison with the conventional ones, because fewer by-products means lower costs for raw materials, for separation and for disposal treatments; but also it implies an increase of productivity and, as a consequence, smaller reactors can be used. In addition, an indirect gain could derive from the better public image of the company, marketing sustainable products or processes. In this context, oxidation reactions play a major role, being the tool for the production of huge quantities of chemical intermediates and specialties. Potentially, the impact of these productions on the environment could have been much worse than it is, if a continuous efforts hadn’t been spent to improve the technologies employed. Substantial technological innovations have driven the development of new catalytic systems, the improvement of reactions and process technologies, contributing to move the chemical industry in the direction of a more sustainable and ecological approach. The roadmap for the application of these concepts includes new synthetic strategies, alternative reactants, catalysts heterogenisation and innovative reactor configurations and process design. Actually, in order to implement all these ideas into real projects, the development of more efficient reactions is one primary target. Yield, selectivity and space-time yield are the right metrics for evaluating the reaction efficiency. In the case of catalytic selective oxidation, the control of selectivity has always been the principal issue, because the formation of total oxidation products (carbon oxides) is thermodynamically more favoured than the formation of the desired, partially oxidized compound. As a matter of fact, only in few oxidation reactions a total, or close to total, conversion is achieved, and usually the selectivity is limited by the formation of by-products or co-products, that often implies unfavourable process economics; moreover, sometimes the cost of the oxidant further penalizes the process. During my PhD work, I have investigated four reactions that are emblematic of the new approaches used in the chemical industry. In the Part A of my thesis, a new process aimed at a more sustainable production of menadione (vitamin K3) is described. The “greener” approach includes the use of hydrogen peroxide in place of chromate (from a stoichiometric oxidation to a catalytic oxidation), also avoiding the production of dangerous waste. Moreover, I have studied the possibility of using an heterogeneous catalytic system, able to efficiently activate hydrogen peroxide. Indeed, the overall process would be carried out in two different steps: the first is the methylation of 1-naphthol with methanol to yield 2-methyl-1-naphthol, the second one is the oxidation of the latter compound to menadione. The catalyst for this latter step, the reaction object of my investigation, consists of Nb2O5-SiO2 prepared with the sol-gel technique. The catalytic tests were first carried out under conditions that simulate the in-situ generation of hydrogen peroxide, that means using a low concentration of the oxidant. Then, experiments were carried out using higher hydrogen peroxide concentration. The study of the reaction mechanism was fundamental to get indications about the best operative conditions, and improve the selectivity to menadione. In the Part B, I explored the direct oxidation of benzene to phenol with hydrogen peroxide. The industrial process for phenol is the oxidation of cumene with oxygen, that also co-produces acetone. This can be considered a case of how economics could drive the sustainability issue; in fact, the new process allowing to obtain directly phenol, besides avoiding the co-production of acetone (a burden for phenol, because the market requirements for the two products are quite different), might be economically convenient with respect to the conventional process, if a high selectivity to phenol were obtained. Titanium silicalite-1 (TS-1) is the catalyst chosen for this reaction. Comparing the reactivity results obtained with some TS-1 samples having different chemical-physical properties, and analyzing in detail the effect of the more important reaction parameters, we could formulate some hypothesis concerning the reaction network and mechanism. Part C of my thesis deals with the hydroxylation of phenol to hydroquinone and catechol. This reaction is already industrially applied but, for economical reason, an improvement of the selectivity to the para di-hydroxilated compound and a decrease of the selectivity to the ortho isomer would be desirable. Also in this case, the catalyst used was the TS-1. The aim of my research was to find out a method to control the selectivity ratio between the two isomers, and finally to make the industrial process more flexible, in order to adapt the process performance in function of fluctuations of the market requirements. The reaction was carried out in both a batch stirred reactor and in a re-circulating fixed-bed reactor. In the first system, the effect of various reaction parameters on catalytic behaviour was investigated: type of solvent or co-solvent, and particle size. With the second reactor type, I investigated the possibility to use a continuous system, and the catalyst shaped in extrudates (instead of powder), in order to avoid the catalyst filtration step. Finally, part D deals with the study of a new process for the valorisation of glycerol, by means of transformation into valuable chemicals. This molecule is nowadays produced in big amount, being a co-product in biodiesel synthesis; therefore, it is considered a raw material from renewable resources (a bio-platform molecule). Initially, we tested the oxidation of glycerol in the liquid-phase, with hydrogen peroxide and TS-1. However, results achieved were not satisfactory. Then we investigated the gas-phase transformation of glycerol into acrylic acid, with the intermediate formation of acrolein; the latter can be obtained by dehydration of glycerol, and then can be oxidized into acrylic acid. Actually, the oxidation step from acrolein to acrylic acid is already optimized at an industrial level; therefore, we decided to investigate in depth the first step of the process. I studied the reactivity of heterogeneous acid catalysts based on sulphated zirconia. Tests were carried out both in aerobic and anaerobic conditions, in order to investigate the effect of oxygen on the catalyst deactivation rate (one main problem usually met in glycerol dehydration). Finally, I studied the reactivity of bifunctional systems, made of Keggin-type polyoxometalates, either alone or supported over sulphated zirconia, in this way combining the acid functionality (necessary for the dehydrative step) with the redox one (necessary for the oxidative step). In conclusion, during my PhD work I investigated reactions that apply the “green chemistry” rules and strategies; in particular, I studied new greener approaches for the synthesis of chemicals (Part A and Part B), the optimisation of reaction parameters to make the oxidation process more flexible (Part C), and the use of a bioplatform molecule for the synthesis of a chemical intermediate (Part D).

Von nichtkommutativen Geometrien, ihren Symmetrien und etwas Hochenergiephysik

In den letzten fünf Jahren hat sich mit dem Begriff desspektralen Tripels eine Möglichkeit zur Beschreibungdes an Spinoren gekoppelten Gravitationsfeldes auf(euklidischen) nichtkommutativen Räumen etabliert. Die Dynamik dieses Gravitationsfeldes ist dabei durch diesogenannte spektrale Wirkung, dieSpur einer geeigneten Funktion des Dirac-Operators,bestimmt. Erstaunlicherweise kann man die vollständige Lagrange-Dichtedes (an das Gravitationsfeld gekoppelten) Standardmodellsder Elementarteilchenphysik, also insbesondere auch denmassegebenden Higgs-Sektor, als spektrale Wirkungeines entsprechenden spektralen Tripels ableiten. Diesesspektrale Tripel ist als Produkt des spektralenTripels der (kommutativen) Raumzeit mit einem speziellendiskreten spektralen Tripel gegeben. In der Arbeitwerden solche diskreten spektralen Tripel, die bis vorKurzem neben dem nichtkommutativen Torus die einzigen,bekannten nichtkommutativen Beispiele waren, klassifiziert. Damit kannnun auch untersucht werden, inwiefern sich dasStandardmodell durch diese Eigenschaft gegenüber anderenYang-Mills-Higgs-Theorien auszeichnet. Es zeigt sichallerdings, dasses - trotz mancher Einschränkung - eine sehr große Zahl vonModellen gibt, die mit Hilfe von spektralen Tripelnabgeleitet werden können. Es wäre aber auch denkbar, dass sich das spektrale Tripeldes Standardmodells durch zusätzliche Strukturen,zum Beispiel durch eine darauf ``isometrisch'' wirkendeHopf-Algebra, auszeichnet. In der Arbeit werden, um dieseFrage untersuchen zu können, sogenannte H-symmetrischespektrale Tripel, welche solche Hopf-Isometrien aufweisen,definiert.Dabei ergibt sich auch eine Möglichkeit, neue(H-symmetrische) spektrale Tripel mit Hilfe ihrerzusätzlichen Symmetrienzu konstruieren. Dieser Algorithmus wird an den Beispielender kommutativen Sphäre, deren Spin-Geometrie hier zumersten Mal vollständig in der globalen, algebraischen Sprache der NichtkommutativenGeometrie beschrieben wird, sowie dem nichtkommutativenTorus illustriert.Als Anwendung werden einige neue Beipiele konstruiert. Eswird gezeigt, dass sich für Yang-Mills Higgs-Theorien, diemit Hilfe von H-symmetrischen spektralen Tripeln abgeleitetwerden, aus den zusätzlichen Isometrien Einschränkungen andiefermionischen Massenmatrizen ergeben. Im letzten Abschnitt der Arbeit wird kurz auf dieQuantisierung der spektralen Wirkung für diskrete spektraleTripel eingegangen.Außerdem wird mit dem Begriff des spektralen Quadrupels einKonzept für die nichtkommutative Verallgemeinerungvon lorentzschen Spin-Mannigfaltigkeiten vorgestellt.

Ein, zwei Punkte zu Nichtkommutativer Geometrie und Quantenfeldtheorie auf diskreten Räumen

Über viele Jahre hinweg wurden wieder und wieder Argumente angeführt, die diskreten Räumen gegenüber kontinuierlichen Räumen eine fundamentalere Rolle zusprechen. Unser Zugangzur diskreten Welt wird durch neuere Überlegungen der Nichtkommutativen Geometrie (NKG) bestimmt. Seit ca. 15Jahren gibt es Anstrengungen und auch Fortschritte, Physikmit Hilfe von Nichtkommutativer Geometrie besser zuverstehen. Nur eine von vielen Möglichkeiten ist dieReformulierung des Standardmodells derElementarteilchenphysik. Unter anderem gelingt es, auch denHiggs-Mechanismus geometrisch zu beschreiben. Das Higgs-Feld wird in der NKG in Form eines Zusammenhangs auf einer zweielementigen Menge beschrieben. In der Arbeit werden verschiedene Ziele erreicht:Quantisierung einer nulldimensionalen ,,Raum-Zeit'', konsistente Diskretisierungf'ur Modelle im nichtkommutativen Rahmen.Yang-Mills-Theorien auf einem Punkt mit deformiertemHiggs-Potenzial. Erweiterung auf eine ,,echte''Zwei-Punkte-Raum-Zeit, Abzählen von Feynman-Graphen in einer nulldimensionalen Theorie, Feynman-Regeln. Eine besondere Rolle werden Termini, die in derQuantenfeldtheorie ihren Ursprung haben, gewidmet. In diesemRahmen werden Begriffe frei von Komplikationen diskutiert,die durch etwaige Divergenzen oder Schwierigkeitentechnischer Natur verursacht werden könnten.Eichfixierungen, Geistbeiträge, Slavnov-Taylor-Identität undRenormierung. Iteratives Lösungsverfahren derDyson-Schwinger-Gleichung mit Computeralgebra-Unterstützung,die Renormierungsprozedur berücksichtigt.

Nichtkommutative Geometrie und Quantisierung von Raumzeiten und Konfigurationsräumen

Das Standardmodell der Elementarteilchenphysik istexperimentell hervorragend bestätigt, hat auf theoretischerSeite jedoch unbefriedigende Aspekte: Zum einen wird derHiggssektor der Theorie von Hand eingefügt, und zum anderenunterscheiden sich die Beschreibung des beobachtetenTeilchenspektrums und der Gravitationfundamental. Diese beiden Nachteile verschwinden, wenn mandas Standardmodell in der Sprache der NichtkommutativenGeometrie formuliert. Ziel hierbei ist es, die Raumzeit der physikalischen Theoriedurch algebraische Daten zu erfassen. Beispielsweise stecktdie volle Information über eine RiemannscheSpinmannigfaltigkeit M in dem Datensatz (A,H,D), den manspektrales Tripel nennt. A ist hierbei die kommutativeAlgebra der differenzierbaren Funktionen auf M, H ist derHilbertraum der quadratintegrablen Spinoren über M und D istder Diracoperator. Mit Hilfe eines solchen Tripels (zu einer nichtkommutativenAlgebra) lassen sich nun sowohl Gravitation als auch dasStandardmodell mit mathematisch ein und demselben Mittelerfassen. In der vorliegenden Arbeit werden nulldimensionale spektraleTripel (die diskreten Raumzeiten entsprechen) zunächstklassifiziert und in Beispielen wird eine Quantisierungsolcher Objekte durchgeführt. Ein Problem der spektralenTripel stellt ihre Beschränkung auf echt RiemannscheMetriken dar. Zu diesem Problem werden Lösungsansätzepräsentiert. Im abschließenden Kapitel der Arbeit wird dersogenannte 'Feynman-Beweis der Maxwellgleichungen' aufnichtkommutative Konfigurationsräume verallgemeinert.

Suche nach einem leichten Higgs-Boson im Kanal WH ev e bb in pp-Kollisionen bei s=1.96 TeV am DO-Detektor des Tevatron

Eine wichtige Komponente des Standardmodells der Teilchenphysik bildet der Higgs-Mechanismus, der benötigt wird um den vom Standardmodell beschriebenen Teilchen Masse zu verleihen. Dieser Mechanismus beinhaltet jedoch ein weiteres schweres Elementarteilchen das bislang noch nich beobachtet werden konnte. Die Suche nach diesem Teilchen ist eines Hauptziele der derzeitigen Forschung an Teilchenbeschleunigern. Diese Arbeit untersucht die vom D0-Detektor am Tevatron des Fermi National Accelerator Laboratory (FNAL) aufgezeichneten Daten von ppbar-Kollisionen bei einer Schwerpunktsenergie von sqrt{s}=1.96 TeV, um im Kanal WH -> enu bb nach einem leichten Higgs-Boson zu suchen. Darüber hinaus wird der Produktionswirkungsquerschnitt der Wbb-Produktion ermittelt. Für die Analyse stand eine integrierte Luminosität von L=255pb^{-1} zur Verfügung. Zur Selektion dieser Prozesse, werden Ereignisse ausgewählt, die Elektronen und fehlenden Transversalimpuls enthalten, sowie mindestens zwei Jets, die sich als b-Jets identifizieren lassen. Um eine effiziente Selektion zu erhalten, wurden Schnitte auf verschiedene Kenngrößen entwickelt, getestet und optimiert. Aus den selektierten Ereignissen wird der Wbb-Wirkungsquerschnitt ermittelt, der für Ereignisse angegeben wird, in denen die b-Quarks p_T>8 GeV und |eta|<3 erfüllen. Der unter Berücksichtigung des Verzweigungsverhältnisses BR(W->enu)=0.108 errechnete Wert ist sigma(Wbb)=21.8 pb (+15.5; -20.0 pb(sys+stat)). Wegen der geringen Signifikanz der Messung von etwa 1.2sigma wurden die Ereigniszahlen auch zur Berechnung einer oberen Grenze auf den Wirkungsquerschnitt verwendet, die sich bei einem Konfidenzniveau von 95% zu sigma^95(Wbb)=60.9pb ergibt. Ebenso wurden Grenzen auf den WH-Produktionswirkungsquerschnitt ermittelt. Dafür wurde die statistische Methode von Feldman und Cousins angewandt, nachdem sie nach den Vorschlägen von Conrad et al. erweitert worden war, um systematische Unsicherheiten zu berücksichtigen. Für ein Standardmodell Higgs-Boson der Masse 115 GeV kann eine obere Grenze auf den Produktionswirkungsquerschnitt von sigma^{95} (WH)=12.2pb angegeben werden. Für höhere Massen bis 135 GeV werden ähnliche Grenzen ermittelt.