Informaticawetenschappen in het leerplichtonderwijs

Dit standpunt bepleit en beargumenteert de noodzaak om elke jongere een opleiding informaticawetenschappen aan te bieden die toelaat om ’informaticavaardig’ te worden. Informaticavaardigheid gaat verder dan louter ‘digitale geletterdheid’, en houdt ook in dat de jongere in staat moet zijn ‘computationeel’ te denken. Computers zijn onmisbaar geworden, zowel in het professionele leven als in de privésfeer. Om de technologische evolutie te kunnen volgen is het van groot belang dat alle jongeren niet alleen de bestaande technologie leren gebruiken, maar ook de onderliggende werking leren begrijpen. Om de technologische evolutie te kunnen sturen, is het nodig dat voldoende jongeren in staat en gemotiveerd zijn om nieuwe technologie te creëren. Om deze doelstellingen te realiseren, dient het onderwijs van de informatica in het leerplichtonderwijs grondig hervormd te worden. In het basis- en secundair onderwijs dient een basisopleiding informaticawetenschappen opgenomen te worden, waarop in specifieke STEM richtingen voortgebouwd wordt. Een nieuw leerprogramma, goed opgeleide leraars en een goede informatica-infrastructuur zijn broodnodig. Ons leerplichtonderwijs is de belangrijkste actor om volgende generaties voor te bereiden op het leven, zowel professioneel als privé. De digitalisering van onze maatschappij kan haar voordelen alleen waarmaken als het onderwijs aangepast is aan deze digitale realiteit. Informatica- wetenschappen is een autonome wetenschap geworden met haar eigen manier van denken, en haar eigen basisbegrippen, te vergelijken met wiskunde, natuurkunde, en andere wetenschap- pen, die haar plaats in het onderwijs verdient. Het moet duidelijk zijn dat het hier niet gaat over het onderwijs van de traditionele vakken met de steun van informaticahulpmiddelen maar wel over de informaticawetenschappen zelf als vormend vak. Dit standpunt kwam tot stand binnen een werkgroep, opgericht door de KVAB en de Jonge Academie en samengesteld met leden uit diverse academische disciplines, onderwijsdeskundi- gen en actoren uit de bedrijfswereld

Observation of Orbitally Excited B_s Mesons

We report the first observation of two narrow resonances consistent with states of orbitally excited (L=1) B_s mesons using 1 fb^{-1} of ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We use two-body decays into K^- and B^+ mesons reconstructed as B^+ \to J/\psi K^+, J/\psi \to \mu^+ \mu^- or B^+ \to \bar{D}^0 \pi^+, \bar{D}^0 \to K^+ \pi^-. We deduce the masses of the two states to be m(B_{s1}) = 5829.4 +- 0.7 MeV/c^2 and m(B_{s2}^*) = 5839.7 +- 0.7 MeV/c^2.Comment: Version accepted and published by Phys. Rev. Let

Search for charged Higgs bosons in decays of top quarks in p-pbar collisions at sqrt(s) = 1.96 TeV

7 pages, 2 figuresWe report the recent charged Higgs search in top quark decays in 2.2/fb CDF data. This is the first attempt to search for charged Higgs using fully reconstructed mass assuming H->c-sbar in small tan beta region. No evidence of a charged Higgs is observed in the CDF data, hence 95% upper limits are placed at B(t->H+b)We report on the first direct search for charged Higgs bosons decaying into cs̅ in tt̅ events produced by pp̅ collisions at √s=1.96  TeV. The search uses a data sample corresponding to an integrated luminosity of 2.2  fb-1 collected by the CDF II detector at Fermilab and looks for a resonance in the invariant mass distribution of two jets in the lepton+jets sample of tt̅ candidates. We observe no evidence of charged Higgs bosons in top quark decays. Hence, 95% upper limits on the top quark decay branching ratio are placed at B(t→H+b)< 0.1 to 0.3 for charged Higgs boson masses of 60 to 150  GeV/c2 assuming B(H+→cs̅ )=1.0. The upper limits on B(t→H+b) are also used as model-independent limits on the decay branching ratio of top quarks to generic scalar charged bosons beyond the standard model.Peer reviewe

Transverse-momentum and pseudorapidity distributions of charged hadrons in pp collisions at √s=0.9 and 2.36 TeV

Measurements of inclusive charged-hadron transverse-momentum and pseudorapidity distributions are presented for proton-proton collisions at root s = 0.9 and 2.36 TeV. The data were collected with the CMS detector during the LHC commissioning in December 2009. For non-single-diffractive interactions, the average charged-hadron transverse momentum is measured to be 0.46 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 0.9 TeV and 0.50 +/- 0.01 (stat.) +/- 0.01 (syst.) GeV/c at 2.36 TeV, for pseudorapidities between -2.4 and +2.4. At these energies, the measured pseudorapidity densities in the central region, dN(ch)/d eta vertical bar(vertical bar eta vertical bar and pp collisions. The results at 2.36 TeV represent the highest-energy measurements at a particle collider to date

Erratum: Search for supersymmetric particles assuming R-parity non-conservation in e+e- collisions at √s = 192 to 208 GeV (The European Physical Journal C (2004) 36 (1-23) DOI: 10.1140/epjc/s2004-01881-6)

0SCOPUS: er.jinfo:eu-repo/semantics/publishe

Charged and identified particles in the hadronic decay of W bosons and in e+e- → qq̄ from 130 to 200 GeV

Inclusive distributions of charged particles in hadronic W decays are experimentally investigated using the statistics collected by the DELPHI experiment at LEP during 1997, 1998 and 1999, at centre-of-mass energies from 183 to around 200 GeV. The possible effects of interconnection between the hadronic decays of two Ws are not observed. Measurements of the average multiplicity for charged and identified particles in qq̄ and WW events at centre-of-mass energies from 130 to 200 GeV and in W decays are presented. The results on the average multiplicity of identified particles and on the position ξ* of the maximum of the ξp = -log(2p/√s) distribution are compared with predictions of JETSET and MLLA calculations.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Consistent measurements of αs from precise oriented event shape distributions

An updated analysis using about 1.5 million events recorded at √s = Mz with the DELPHI detector in 1994 is presented. Eighteen infrared and collinear safe event shape observables are measured as a function of the polar angle of the thrust axis. The data are compared to theoretical calculations in script O(α2s) including the event orientation. A combined fit of αs and of the renormalization scale xμ in script O(α2s) yields an excellent description of the high statistics data. The weighted average from 18 observables including quark mass effects and correlations is αs(M2z) = 0.1174±0.0026. The final result, derived from the jet cone energy fraction, the observable with the smallest theoretical and experimental uncertainty, is αs(M2z) = 0.1180 ± 0.0006(exp.) ± 0.0013(hadr.) ± 0.0008(scale) ± 0.0007(mass). Further studies include an αs determination using theoretical predictions in the next-to-leading log approximation (NLLA), matched NLLA and script O(α2s) predictions as well as theoretically motivated optimized scale setting methods. The influence of higher order contributions was also investigated by using the method of Padé approximants. Average αs values derived from the different approaches are in good agreement.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Measurement of the B̄ → D(*)πℓν̄ℓ branching fraction

A study of b semileptonic decays into D, Dπ± and D*π± final states is presented. The D0, D+ and D*+ mesons are exclusively reconstructed in Z decay data recorded from 1992 to 1995 in the DELPHI experiment at LEP. The overall branching fractions are measured to be: BR(b→ D0ℓ-νℓX) = (7.04 + 0.34 (stat) + 0.36 (syst.exp) + 0.17 (BRD))%, BR(b→ D+ℓ-νℓX) = (2.72 + 0.19 (stat) + 0.16 (syst.exp) + 0.18 (BRD))%, BR(b→ D*+ℓ-νℓX) = (2.75 + 0.17 (stat) + 0.13 (syst.exp) + 0.09 (BRD))%, where the D0 and D+ results include also contributions from D*0 and D*+ decays. A fit to the distribution of the π± impact parameter to the primary interaction vertex provides a measurement of the b semileptonic branching fractions into the D0π±X, D+π±X and D*+π±X final states. Assuming that single pion decay modes of B mesons dominate, the partial rates for B→Dπℓ-νℓ and B→D*πℓ-νℓ have been obtained, corresponding to a total branching fraction: BR(B→Dπℓ-νℓ) +BR(B→D*πℓ-νℓ) = (3.40 + 0.52 (stat) + 0.32 (syst))%. This result agrees well with the observed difference between the total B semileptonic branching fraction and the sum of the B→Dℓ-νℓ and B→D*ℓ-νℓ branching fractions. © 2000 Elsevier Science B.V.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe