0000000000933705

AUTHOR

Juan José Gómez Cadenas

First evidence of hard scattering processes in single tagged gamma-gamma-collisions

For the first time, multihadronic production from single tagged gammagamma collisions has been studied, where one of the scattered leptons was tagged at very low virtual photon absolute mass squared ( = 0.06GeV/(c2))2 ). Data collected during 1991 and 1992 in the DELPHI experiment at LEP are shown to agree well with predictions which included the non-perturbative vector meson dominance model in which the interacting photons are assumed to have converted into a vector meson (rho, omega or pi), a quark-parton model which describes direct photon interactions and a QCD-based model which considers the photon to have quark and gluon structure functions. Five different parametrizations of these st…

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All that Glitters is not Green

The painter, carrying his easel, walks leisurely across the meadow that extends up to the limits of the summer sky. Under a chestnut tree he prepares his palette and his colors, then stretches and smiles. He is wearing a cotton shirt and slacks; a straw hat covers his curly hair. He walks barefoot because he likes the feel of the grass under his feet. This painter loves nature; he loves nature as an artist and as a scientist. This painter is a nuclear physicist, and his job consists in harnessing the elementary power of the atom, the one that makes the stars glow, in order to generate the power and hydrogen his town uses.

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Search for nu(mu) -> nu(e) oscillations in the NOMAD experiment

We present the results of a search for nu(mu) --> nu(e) oscillations in the NOMAD experiment at CERN. The experiment looked for the appearance of nu(e) in a predominantly nu(mu) wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are Deltam(2) < 0.4 eV(2) for maximal mixing and sin(2) (20) < 1.4 x 10(-3) for large Deltam(2). This result excludes the LSND allowed region of oscillation parameters with Deltam(2) greater than or similar to 10 eV(2).

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A measurement of b+ and b-0 lifetimes using (d)over-bar-l(+) events

A measurement of B meson lifetimes is presented using data collected from 1991 to 1993 by the DELPHI detector at the LEP collider. Samples of events with a D meson and a lepton in the same jet are selected where D¯0ℓ+ and D*ℓ+ events originate mainly from the semileptonic decays of B+ and B0 mesons, respectively. From the reconstructed B decay length and the estimated B momentum, taking into account the dilution due to B decays into D¯∗∗ℓ+v , the following B meson lifetimes and lifetime ratio are measured: τ(B+)=1.61+0.16−0.16(stat.)±0.12(syst.)psτ(B0)=1.61+0.14−0.13(stat.)±0.08(syst.)psτ(B+)/τ(B0)=1.00+0.17−0.15(stat.)±0.10(syst.) and an average lifetime of B+ and B0 mesons is obtained: τ(…

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Helios and Aeolus

In summer it’s always hot in the Big Apple, but the summer of 2003 had been especially sweltering. Temperatures had been around 35oC during all the month, with humidity approaching one hundred percent. The higher the temperature, the lower the New Yorkers’ thermostats, up to the point where you needed a sweater at the office, while outside delivery men, mail carriers and peddlers had to suffer the heat, together with the tourists brave enough to venture through the smoldering avenues.

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Search for pair-produced heavy scalars in Z° decays

A search for charged Higgs bosons decaying into quarks is described, based on statistics of around 1.7 million hadronic Z0 decays detected in DELPHI. Despite the very high background from standard hadronic decays of the Z0, masses in the range up to 43.5 GeV/c2 are excluded at the 95% con dence level. After combination with a search for leptonic decays, this mass limit is extended to cover all branching ratios. A similar analysis sets new limits on the possible production of any pair-produced heavy scalar decaying into a pair of jets, such as neutral Higgs bosons in a two doublet scheme and diquarks.

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Nuclear Power, No Thanks?

The greatest misunderstanding related to nuclear energy, which is continuously exploited by its opponents, is the nature of radioactivity. Pierre and Marie Curie carried in the pockets of their laboratory coats test tubes full of highly radioactive substances, unaware that gamma radiation could be harmful at high doses. In contrast, antinuclear propaganda has been so effective that most people are convinced that any radioactive “leakage” is deadly or that radioactive waste has to be buried at a depth of kilometers to avoid harmful effects—in fact, a few meters of soil is enough to absorb even the most intense gamma radiation—or that cancer risk grows exponentially due to nuclear power plant…

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Study of prompt photon production in hadronic Z° decays.

From a sample of 1.5 million Z0 ! qq decays collected by the DELPHI detector during 1991, 1992 and 1993, the production cross section for isolated nal state photons is measured and is compared with the O( ; s) matrix element calculations implemented in the EEPRAD and GNJETS Monte Carlo generators. The observed photon yield is used to derive the electroweak couplings of charge 2/3 (u-type) and charge 1/3 (d-type) quarks to the Z0 boson. The measured values c2=3 = 0:91+0:25 0:36 and c1=3 = 1:62+0:24 0:17 are compatible with the Standard Model prediction, c2=3 = 1:145 and c1=3 = 1:477.

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A Measurement of B Meson Production and Lifetime Using D`− Events in Z0 Decays

A study of B meson decays into D l- X final states is presented. In these events, neutral and charged D mesons originate predominantly from B+ and B0 decays, respectively. The dilution of this correlation due to D** production has been taken into account. From 263700 hadronic Z0 decays collected in 1991 with the DELPHI detector at the LEP collider, 92 D0 --> K- pi+, 35 D+ --> K- pi+ pi+ and 61 D*+ --> D0 pi+ followed by D0 --> K- pi+ or D0 --> K- pi+ pi+ pi-, are found with an associated lepton of the same charge as the kaon. From the D0 l- and D*+ l-, the probability f(d) that a b quark hadronizes into a B- (or B0BAR),meson is found to be 0.44 +/-0.08 +/-0.09, corresponding to a total (B(s…

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Estudio del calorimetro electromagnético forward de Delphi : Aplicación a la búsqueda del Boson de Higgs HO en LEP-I

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Study of orientation of 3-Jet events in Z(0) hacronic decays using the DELPHY detector

The study of the orientation of three-jet events from e+ e- --> Z0 --> multi-hadrons is presented, in particular the polar angle distributions of the thrust axis and of the normal to the three-jet plane, and the azimuthal correlations between the hadron plane and the one defined by the beam and thrust axes. The data are compared with results at lower energy and with QCD predictions. Good agreement with QCD predictions is observed. The scalar gluon theory is excluded by the data.

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A Wasted Inheritance

We all know how Aladdin escapes when the sorcerer traps him in the magic cave. He finds a lamp, rubs it, and a powerful genie appears, who will grant him all his wishes. To start with, he takes him home swiftly, though perhaps not as fast as if he had boarded an Airbus or a high-speed train. Then he loads his table with delicious food, almost as plentiful and varied as can be found in our refrigerators. Finally, he dresses him in luxurious silk clothes, like the ones you can get at the sales in Macy’s. The young boy grows confident and relishes in his pleasant life, taking it for granted that he deserves everything he is profiting from.

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Measurement of the B0 - anti-B0 mixing using the average electric charge of hadron jets in Z0 decays

From the data recorded with the DELPHI detector at LEP in the years 1991-1992, 46 497 events were selected having a high-momentum muon in hadron jets. A fit to the average electric charge sum of the jets recoiling against a b-quark jet tagged by a high-PT muon results in an average mixing parameter of chiBAR = 0.144 +/- 0.014(stat.)+0.017/-0.011(syst.).

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Measurement of the quasi-elastic axial vector mass in neutrino-oxygen interactions

The weak nucleon axial-vector form factor for quasielastic interactions is determined using neutrino interaction data from the K2K Scintillating Fiber detector in the neutrino beam at KEK. More than 12 000 events are analyzed, of which half are charged-current quasielastic interactions nu(mu)n ->mu(-)p occurring primarily in oxygen nuclei. We use a relativistic Fermi gas model for oxygen and assume the form factor is approximately a dipole with one parameter, the axial-vector mass M-A, and fit to the shape of the distribution of the square of the momentum transfer from the nucleon to the nucleus. Our best fit result for M-A=1.20 +/- 0.12 GeV. Furthermore, this analysis includes updated vect…

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Forward pi(+/-) production in p-O-2 and p-N-2 interactions at 12 GeV/c

Measurements of double-differential charged pion production cross-sections in interactions of 12 GeV/c protons on O-2 and N-2 thin targets are presented in the kinematic range 0.5 GeV/c <= p(pi) < 8 GeV/c and 50 mrad <= 0(pi) < 250 mrad (in the laboratory frame) and are compared with p-C results. For p-N-2 (p-O-2) interactions the analysis is performed using 38576 (7522) reconstructed secondary pions. The analysis uses the beam instrumentation and the forward spectrometer of the HARP experiment at CERN PS. The measured cross-sections have a direct impact on the precise calculation of atmospheric neutrino fluxes and on the improved reliability of extensive air shower simulations by reducing …

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Measurement of the Lambda polarization in nu(mu) charged current interactions in the NOMAD experiment

The Lambda polarization in upsilon (mu) charged current interactions has been measured in the NOMAD experiment. The event sample (8087 reconstructed Lambda 's) is more than an order of magnitude larger than that of previous bubble chamber experiments, while the quality of event reconstruction is comparable. We observe negative polarization along the W-boson direction which is enhanced in the target fragmentation region: P-x(x(F) 0) = -0.09 +/- 0.06(stat) +/- 0.03(sys). These results provide a test of different models describing the nucleon spin composition and the spin transfer mechanisms. A significant transverse polarization tin the direction orthogonal to the Lambda production plane! has…

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On Board the Nautilus

Some months ago, I took part, with some friends, in an astronomy trip to the mountain Pico del Buitre, in Javalambre (province of Teruel, Spain). The trip, among whose participants there were prospective scientists between the age of four and nine, included a night devoted to amateur observation with portable telescopes. El Pico del Buitre is one of the darkest spots in Spain—and also one of the coldest, as all members of the party remember well. Even darker is Roque de los Muchachos, on Las Palmas (Gran Canaria, Canary Islands), one of the most important sites for astronomy observation on the Northern hemisphere.

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The Bequest of a Supernova

Hanabi translates as “fireworks”, but the Japanese expression is formed by joining the kanjis “hana”, one of whose meanings is “flower”, and “bi”, “fire”. That’s literally “fire flower”.

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Characterisation of NEXT-DEMO using xenon K-alpha X-rays

The NEXT experiment aims to observe the neutrinoless double beta decay of 136Xe in a high-pressure xenon gas TPC using electroluminescence (EL) to amplify the signal from ion- ization. Understanding the response of the detector is imperative in achieving a consistent and well understood energy measurement. The abundance of xenon K-shell X-ray emission during data tak- ing has been identified as a multitool for the characterisation of the fundamental parameters of the gas as well as the equalisation of the response of the detector. The NEXT-DEMO prototype is a ∼ 1.5 kg volume TPC filled with natural xenon. It employs an array of 19 PMTs as an energy plane and of 256 SiPMs as a tracking plane…

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A Study of radiactive muon-pair events at Z° energies and limits on an additional Z' gauge boson

An analysis is reported on the channele + e −→μ+μ−(nγ), n=1,2..., using data taken with the DELPHI detector at LEP from 1990 to 1992. Differential cross sections of the radiative photons as a function of photon energy and of the angle between the photon and the muon are presented. No significant deviations from expectations are observed. The data are also used to extract the muon-pair cross section and asymmetry below the Z0 peak by using those events with relatively hard initial state radiative photon(s). The measured cross section and asymmetry show no significant deviation from the Standard Model expectations. These results together with the DELPHI cross section and asymmetry measurement…

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Determination of alpha-s in second order QCD from hadronic Z decays

Distributions of event shape variables obtained from 120600 hadronic Z decays measured with the DELPHI detector are compared to the predictions of QCD based event generators. Values of the strong coupling constant alpha(s) are derived as a function of the renormalization scale from a quantitative analysis of eight hadronic distributions. The final result, alpha(s) (M(Z)) = 0.113 +/- 0.007, is based on second order perturbation theory and uses two hadronization corrections, one computed with a parton shower model and the other with a QCD matrix element model.

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A study of backward going protons and negative pions in Numu CC interactions with the NOMAD detector

Backward proton and π− production has been studied in νμCC interactions with carbon nuclei. Detailed analyses of the momentum distributions, of the production rates, and of the general features of events with a backward going particle, have been carried out in order to understand the mechanism producing these particles. The backward proton data have been compared with the predictions of the reinteraction and the short range correlation models.

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Measurement of the Antilambda Polarisation in Nu(mu) Charged Current Interactions in the NOMAD Experiment

We present a measurement of the polarization of Antilambda hyperons produced in nu_mu charged current interactions. The full data sample from the NOMAD experiment has been analyzed using the same V0 identification procedure and analysis method reported in a previous paper for the case of Lambda hyperons. The Antilambda polarization has been measured for the first time in a neutrino experiment. The polarization vector is found to be compatible with zero.

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Production of strange b-baryons decaying into xi-/+-l-/+ pairs at LEP

An excess of events containing, in a jet, a same-sign Xi(-/+) - l(-/+) pair as compared to those with an opposite-sign Xi(-/+) - l(-/+) pair has been observed in an analysis of 1.7 million hadronic Z(o) decays collected by the DELPHI detector at LEP between 1991 and 1993 inclusive. The probability for this signal to come from non B-baryon decays is less than 5 x 10(-4). The measured production fraction corresponds to: P(b --> B - baryon) x BR(B - baryon --> Xi(-) l(-) X) = (5.9 +/- 2.1 +/- 1.0) x 10(-4), per lepton species, averaged for electrons and muons and assuming the two channels have an equal contribution. Semileptonic decays of Lambda(b) baryons can account for less than 10% of thes…

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The Sacred Fire

The fire on Mount Parnassus that gave rise to the temple of the Oracle of Delphi was not the only spontaneous outflow of natural gas known to the Ancient World. People in ancient India, Persia and China knew about these fen fires, and there they also used to attribute them to supernatural causes, at least until 500 BC, when the Chinese built the first gas pipelines––using bamboo!––many centuries ahead of the West, as on many other occasions.

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Near-intrinsic energy resolution for 30-662 keV gamma rays in a high pressure xenon electroluminescent TPC

We present the design, data and results from the NEXT prototype for Double Beta and Dark Matter (NEXT-DBDM) detector, a high-pressure gaseous natural xenon electroluminescent time projection chamber (TPC) that was built at the Lawrence Berkeley National Laboratory. It is a prototype of the planned NEXT-100 Xe-136 neutrino-less double beta decay (0 nu beta beta) experiment with the main objectives of demonstrating near-intrinsic energy resolution at energies up to 662 keV and of optimizing the NEXT-100 detector design and operating parameters. Energy resolutions of similar to 1% FWHM for 662 keV gamma rays were obtained at 10 and 15 atm and similar to 5% FWHM for 30 keV fluorescence xenon X-…

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The Anti Nuclear Litany

Can nuclear energy become a viable alternative to fossil fuels? Almost all of French electricity is generated in nuclear plants, as is half of the electricity in Ukraine, Sweden and Belgium, a third in Finland and South Korea and a fifth in many other countries, among them Spain, Germany, the UK and the USA.

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Production of Lambda and Lambda anti-Lambda correlations in the hadronic decays of the Z (0)

An analysis of the production of the LAMBDA baryon in the hadronic decays of the Z0 is presented, based on about 993K multihadronic events collected by the DELPHI detector at LEP during 1991 and 1992. The differential cross section of the LAMBDA and the correlations between LAMBDA and LAMBDABAR produced in the same event are compared to current models, based both on string fragmentation and on cluster decay. The predictions of the string fragmentation model are found to give satisfactory agreements with the data, clearly better than those of the cluster model.

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Measurement of the triple-gluon vertex from 4-JET events at LEP

From the combined data of 1990 and 1991 of the DELPHI experiment at LEP, 13057 4-jet events are obtained and used for determining the contribution of the triple-gluon vertex. The relevant variables are the generalized Nachtmann Reiter angle theta(NR)* and the opening angle of the two least energetic jets. A fit to their two-dimensional distribution yields C(A)/C(F)=2.12+/-0.35 and N(C)/N(A)=0.46+/-0.19, where C(A)/C(F) is the ratio of the coupling strength of the triple-gluon vertex to that of gluon bremsstrahlung from quarks, and N(C)/N(A), the ratio of the number of quark colours to the number of gluons. This constitutes a convincing model-independent proof of the existence of the triple-…

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Manna Springing from the Earth

At one of my aunt’s, there was an illustrated children’s edition of the Bible. I was six or seven years old, and on Saturday afternoons she would often take care of me. It was a fortunate deal everybody gained from. My parents were free to do the shopping and get some fresh air. My aunt enjoyed stuffing me with biscuits and milk, but not as much as I enjoyed the adventures of the Bible lands: Yahweh furiously unleashing plagues on the Pharaoh, the miraculous escape from Egypt, with the Red Sea saving the tribes, in extremis, from Ramses’ troops; the great king on his knees, watching the bodies of his drowned soldiers, wondering why God might favor a bunch of goat keepers; Moses wandering th…

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Upper limits on the branching ratios tau-]mu-gamma and tau-]e-gamma

The DELPHI collaboration has searched for lepton flavour violating decays tau -> mugamma and tau -> egamma using a data sample of about 70 pb-1 of integrated luminosity corresponding to 81 000 produced tau+tau- events. No candidates were found for either of the two modes. This yields branching ratio upper limits of B(tau -> egamma) mugamma) < 6.2 × 10-5 at 90% confidence level.

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Fukushima, or the Black Swan of Nuclear Energy

By its own merits, the great earthquake that hit Japan on 11 March 2011 would have qualified as one of the worse disasters of recent times. With a magnitude of 9.0 MW, it was the most powerful known earthquake ever to have hit Japan, and one of the most powerful in history. It released a surface energy 2 × 1017 Joule. Enough, if harnessed, to power a city the size of Los Angeles for an entire year.

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Determination of alpha(s) using the next-to-leading-log approximation of QCD

A new measurement of alpha(s), is obtained from the distributions in thrust, heavy jet mass, energy-energy correlation and two recently introduced jet broadening variables following a method proposed by Catani, Trentadue, Turnock and Webber. This method includes the full calculation of O(alpha(s)2) terms and leading and next-to-leading logarithms resummed to all orders of alpha(s). The analysis is based on data taken with the DELPHI detector at LEP during 1991. I its found that the inclusion of the resummed leading and next-to-leading logarithms reduces the scale dependence of alpha(s) and allows an extension of the fit range towards the infrared limit of the kinematical range. The combined…

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A precise measurement of the muon neutrino nucleon inclusive charged current cross section off an isoscalar target in the energy range 2.5<E<40 GeV by NOMAD

We present a measurement of the muon neutrino-nucleon inclusive charged current cross section, off an isoscalar target, in the neutrino energy range 2.5 <= E-v <= 40 GeV. The significance of this measurement is its precision, +/- 4% in 2.5 <= E-v <= 10 GeV, and +/- 2.6% in 10 <= E-v <= 40 GeV regions, where significant uncertainties in previous experiments still exist, and its importance to the current and proposed long baseline neutrino oscillation experiments.

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Final NOMAD results on nu(mu) -> nu(tau) and nu(e) -> nu(tau) oscillations including a new search for nu(tau) appearance using hadronic tau decays

Results from the v, appearance search in a neutrino beam using the full NOMAD data sample are reported. A new analysis unifies all the hadronic tau decays, significantly improving the overall sensitivity of the experiment to oscillations. The 'blind analysis' of all topologies yields no evidence for an oscillation signal. In the two-family oscillation scenario, this sets a 90% CL allowed region in the sin(2)2 theta (mu tau)-Deltam(2) plane which includes sin(2)2 theta (mu tau) nu (tau) oscillation hypothesis results in sin(2) 2 theta (l tau) < 1.5 x 10(-2) at large Deltam(2) and Deltam(2) < 5.9 eV(2)/c(4) at sin(2) 2 theta (l tau) = 1. We also derive limits on effective couplings of the tau…

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Measurement of the production cross-sections of pi(+/-) in p-C and pi(+/-)-C interactions at 12 GeV/c

The results of the measurements of the double-differential production cross-sections of pions, d(2)sigma(pi)/dpd Omega, in p-C and pi(+/-)-C interactions using the forward spectrometer of the HARP experiment are presented. The incident particles are 12 GeV/c protons and charged pions directed onto a carbon target with a thickness of 5% of a nuclear interaction length. For p-C interactions the analysis is performed using 100,035 reconstructed secondary tracks, while the corresponding numbers of tracks for pi(-)-C and pi(+)-C analyses are 106,534 and 10,122, respectively. Cross-section results are presented in the kinematic range 0.5 GeV/c <= p(pi) < 8 GeV/c and 30 mrad <= theta(pi) < 240 mra…

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Precision measurement of scaled momentum, charge multiplicity, and thrust in nu N-mu and (nu)over-bar(mu)N interactions

We report the first precision measurements of the scaled momentum, the charge multiplicity, and the thrust of hadronic jets in the Breit frame in Deep Inelastic Scattering nu(mu)N and charged cur rent events over the Q(2) range from 1 to 100 GeV2. The neutrino data, obtained in the NOMAD experiment at the CERN SPS, extend the Q(2)-evolution of these parameters by two orders of magnitude, and with commensurate precision, when compared to those reported by the ep and e(+)e(-) experiments

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Experimental study of the atmospheric neutrino backgrounds for p -> e(+)pi(0) searches in water Cherenkov detectors

The atmospheric neutrino background for proton decay via p -> e(+)pi(0) in ring imaging water Cherenkov detectors is studied with an artificial accelerator neutrino beam for the first time. In total, 3.14x10(5) neutrino events corresponding to about 10 megaton-years of atmospheric neutrino interactions were collected by a 1000 ton water Cherenkov detector (KT). The KT charged-current single pi(0) production data are well reproduced by simulation programs of neutrino and secondary hadronic interactions used in the Super-Kamiokande (SK) proton decay search. The obtained p -> e(+)pi(0) background rate by the KT data for SK from the atmospheric neutrinos whose energies are below 3 GeV is 1.63(-…

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A more sensitive search for nu(mu) -> nu(tau) oscillations in NOMAD

With additional data and improved algorithms, we have enhanced the sensitivity of our appearance search for nu(mu) --> nu(tau) oscillations in the NOMAD detector in the CERN-SPS wide-band neutrino beam. The search uses kinematic criteria to identify nu(tau) charged current interactions followed by decay of the tau(-) to one of several decay modes. Our 'blind'' analyses of deep-inelastic scattering data taken in 1996 and 1997, combined with consistent reanalyses of previously reported 1995 data, yield no oscillation signal. For the two-family oscillation scenario, we present the contour outlining a 90% C.L. confidence region in the sin(2)2 theta(mu tau) - Delta m(2) plane. At large Delta m(2…

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Limit on nu(e) -> nu(tau) oscillations from the NOMAD experiment

In the context of a two-flavour approximation we reinterpret the published NOMAD limit on νμ→ντ oscillations in terms of νe→ντ oscillations. At 90% C.L. we obtain Full-size image (<1 K) for large Δm2, while for sin22θeτ=1 the confidence region includes Δm2<11 eV2/c4.

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Measurement of the production cross-section of positive pions in p-Al collisions at 12.9 GeV/c

A precision measurement of the double-differential production cross-section, d(2)sigma(pi+)/dpd Omega for pions of positive charge. performed in the HARP experiment is presented. The incident particles are protons of 12.9 GeV/c momentum impinging on an aluminium target of 5% nuclear interaction length. The measurement of this cross-section has a direct application to the calculation of the neutrino flux of the K2K experiment. After cuts, 210000 secondary tracks reconstructed in the forward spectrometer were used in this analysis. The results are given for secondaries within a momentum range from 0.75 to 6.5 GeV/c. and within an angular range from 30 mrad to 2 10 mrad. The absolute normaliza…

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Improved search for nu(mu)->nu(e) oscillation in a long-baseline accelerator experiment

We performed an improved search for nu(mu)->nu(e) oscillation with the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment, using the full data sample of 9.2x10(19) protons on target. No evidence for a nu(e) appearance signal was found, and we set bounds on the nu(mu)->nu(e) oscillation parameters. At Delta m(2)=2.8x10(-3) eV(2), the best-fit value of the K2K nu(mu) disappearance analysis, we set an upper limit of sin(2)2 theta(mu e)< 0.13 at a 90% confidence level.

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Measurement of gamma(b(b)over-bar)/gamma(had) using impact parameter measurements and lepton identification

The partial decay width of theZ to bb¯quark pairs has been measured by the DELPHI detector at LEP.b-hadrons, containingb-quarks, were tagged by leptons with high transverse momentum relative to the hadron or by tracks with large impact parameters to the primary vertex.The ratio of the numbers of events with a single such tag to those with two tags was used to estimate the efficiency of the method and to reduce the systematic uncertainty. Combining all methods, the value: Γbb¯Γhad=0.2210±0.0033±0.0003(model)±0.0014(Γcc¯) was found, where the third error corresponds to a±8% uncertainty on the cc production width. A maximum likelihood in to the single and di-lepton distributions gave the branc…

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The Ignoble Fuel

Perhaps the first historic mention of a substance derived from coal goes back to the Bible, when Yahweh orders Noah to build the famous ark.

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