CMS Use of a Data Federation

CMS is in the process of deploying an Xrootd based infrastructure to facilitate a global data federation. The services of the federation are available to export data from half the physical capacity and the majority of sites are configured to read data over the federation as a back-up. CMS began with a relatively modest set of use-cases for recovery of failed local file opens, debugging and visualization. CMS is finding that the data federation can be used to support small scale analysis and load balancing. Looking forward we see potential in using the federation to provide more flexibility in the location workflows are executed as the difference between local access and wide area access are diminished by optimization and improved networking. In this presentation we discuss the application development work and the facility deployment work, the use-cases currently in production, and the potential for the technology moving forward

CMS Use of a Data Federation

CMS is in the process of deploying an Xrootd based infrastructure to facilitate a global data federation. The services of the federation are available to export data from half the physical capacity and the majority of sites are configured to read data over the federation as a back-up. CMS began with a relatively modest set of use-cases for recovery of failed local file opens, debugging and visualization. CMS is finding that the data federation can be used to support small scale analysis and load balancing. Looking forward we see potential in using the federation to provide more flexibility in the location workflows are executed as the difference between local access and wide area access are diminished by optimization and improved networking. In this presentation we discuss the application development work and the facility deployment work, the use-cases currently in production, and the potential for the technology moving forward

Search for B\u3csub\u3es\u3c/sub\u3e\u3csup\u3e0\u3c/sup\u3e→µ\u3csup\u3e+\u3c/sup\u3eµ\u3csup\u3e-\u3c/sup\u3e and B\u3csub\u3ed\u3c/sub\u3e\u3csup\u3e0\u3c/sup\u3e→µ\u3csup\u3e+\u3c/sup\u3eµ\u3csup\u3e-\u3c/sup\u3e Decays in \u3ci\u3ep\u3c/i\u3e\u3csup\u3eρ̅\u3c/sup\u3e Collisions with CDF II

We report on a search for Bs0→µ+µ- and Bd0→µ+µ- decays in pρ̅ collisions at √8=1.96 TeV using 364 pb-1 of data collected by the CDF II detector at the Fermilab Tevatron Collider. After applying all selection requirements, we observe no candidates inside the Bs0 or Bd0 mass windows. The resulting upper limits on the branching fractions are Ɓ (Bs0→µ+µ-)\u3c1.5×10-7 and Ɓ (Bd0→µ+µ-)\u3c3.9×10-8 at 90% confidence level

Top-Quark Mass Measurement from Dilepton Events at CDF II

We report a measurement of the top-quark mass using events collected by the CDF II detector from pp̅ collisions at √s = 1.96 TeV at the Fermilab Tevatron. We calculate a likelihood function for the top-quark mass in events that are consistent with tt̅ → b̅ℓ-ν̅ℓbℓ′+ν′ℓ decays. The likelihood is formed as the convolution of the leading-order matrix element and detector resolution functions. The joint likelihood is the product of likelihoods for each of 33 events collected in 340 pb-1 of integrated luminosity, yielding a top-quark mass Mt = 165.2 ± 6.1(stat) ± 3.4(syst) GeV/c2. This first application of a matrix-element technique to tt̅ → bℓ+νℓb̅ℓ′-ν̅ℓ′ decays gives the most precise single measurement of Mt in dilepton events. Combined with other CDF run II measurements using dilepton events, we measure Mt = 167.9 ± 5.2(stat) ± 3.7(syst) GeV/c2

Measurement of the azimuthal angle distribution of leptons from\u3ci\u3eW\u3c/i\u3e boson decays as a function of the \u3ci\u3eW\u3c/i\u3e transverse momentum in \u3ci\u3epp̅\u3c/i\u3e collisions at √s = 1.8 TeV

We present the first measurement of the A2 and A3 angular coefficients of the W boson produced in proton-antiproton collisions. We study W → e νe and W → e νe candidate events produced in association with at least one jet at CDF, during Run Ia and Run Ib of the Tevatron at √s =1:8 TeV. The corresponding integrated luminosity was 110 pb-1. The jet balances the transverse momentum of the W and introduces QCD effects in W boson production. The extraction of the angular coefficients is achieved through the direct measurement of the azimuthal angle of the charged lepton in the Collins-Soper rest-frame of the W boson. The angular coefficients are measured as a function of the transverse momentum of the W boson. The electron, muon, and combined results are in good agreement with the standard model prediction, up to order αs2 in QCD

Measurement of the mass splittings between the \u3ci\u3ebb̅\u3c/i\u3eχ\u3csub\u3eb,J\u3c/sub\u3e(1\u3ci\u3eP\u3c/i\u3e) states

We present new measurements of photon energies and branching fractions for the radiative transitions Υ(2S) → γχb(J=0,1,2)(1P). The masses of the χb states are determined from the measured radiative photon energies. The ratio of mass splittings between the χb substates, r ≡ [(MJ=2 -MJ=1)/( MJ=1 - MJ=0), with M the χb mass, provides information on the nature of the bb̅ confining potential. We find r(1P)=0.542 ±0.022±0.024. This value is somewhat lower than the previous world average, but more consistent with the theoretical expectation that r(1P) \u3c r(2P); i.e., that this mass splitting ratio is smaller for the χb (1P) states than for the χb (2P) states

Observation of the Decay \u3ci\u3eD\u3c/i\u3e\u3csub\u3es\u3c/sub\u3e\u3csup\u3e+\u3c/sup\u3e → ωπ\u3csup\u3e+\u3c/sup\u3e

Using e+e- annihilation data collected by the CLEO II detector at CESR, we have observed the decay Ds+ → ωπ+. This final state may be produced through the annihilation decay of the i\u3eDs+, or through final state interactions. We find a branching ratio of γ(Ds+ → ωπ+)/γ(Ds+ →ηπ+) = 0.16±0.04±0.03, where the first error is statistical and the second is systematic

Evidence for \u3ci\u3eB\u3c/i\u3e\u3csup\u3e0\u3c/sup\u3e → ρ\u3csup\u3e0\u3c/sup\u3e ρ\u3csup\u3e0\u3c/sup\u3e Decays and Implications for the Cabibbo-Kobayashi-Maskawa Angle α

We search for the decays B0 → ρ0 ρ0, B0 → ρ0f0(980), and B0 → f0(980)f0(980) in a sample of about 384 × 106 Υ (4S)→ BB̅ decays collected with the BABAR detector at the PEP-II asymmetric-energy ℯ+ ℯ- collider at Stanford Linear Accelerator Center. We find evidence for B0 → ρ0 ρ0 with 3.5σ significance and measure the branching fraction Ɓ = 1.07 ± 0:33 ± 0:19) × 10-6 and longitudinal polarization fraction fL = 0.87 ± 0.13 ± 0.04, where the first uncertainty is statistical, and the second is systematic. The uncertainty on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix unitarity angle α due to penguin contributions in B→ ρρ decays is 18° at the 1σ level. We also set upper limits on the B0 → ρ0f0(980) and i\u3eB0 → f0(980)f0(980) decay rates

Hadronic transitions Υ(2\u3ci\u3eS\u3c/i\u3e)→Υ(1\u3ci\u3eS\u3c/i\u3e)

Using a 73.6 pb-1 data sample of Υ(2S) events collected with the CLEO II detector at the Cornell Electron Storage Ring, we have investigated the hadronic transitions between the Υ(2S) and the Υ(1S). The dipion transition Υ(2S) → Υ(1S) π+π- was studied using two different analysis techniques. Selecting events in which Υ(1S) → e+e-, μ+μ- (‘‘exclusive’’ analysis), and using the Υ(1S) leptonic branching fractions world averages from the PDG review, we obtained Ɓ(Υ(2S) → Υ(1S) π+π-) =0.189±0.004±0.010, while using a method allowing Υ(1S) → anything (‘‘inclusive’’ analysis) we obtained Ɓ(Υ(2S) → Υ(1S) π+π-) = 0.196 ±0.002±0.010. The appropriate weighted average of the two measurements gives Ɓ(Υ(2S) → Υ(1S) π+π-) = 0.192±0.002±0.010. Combining the exclusive and inclusive results we derive the Υ(1S) leptonic branching fractions Bee = 0.0229±0.0008±0.0011 and Bμμ = 0.0249±0.0008±0.0013. We also studied Υ(2S) → Υ(1S) π0π0 and obtained Ɓ(Υ(2S) → Υ(1S) π0π0) = 0.092±0.006±0.008. Parameters of the π π system (dipion invariant mass spectra, angular distributions) were analyzed and found to be consistent with current theoretical models. Lastly, we searched for the η and single π0 transitions and obtained the 90% confidence level upper limits Ɓ(Υ(2S) → Υ(1S) η) \u3c 0.0028 and Ɓ(Υ(2S) → Υ(1S) π0) \u3c 0.0011

New limits for neutrinoless tau decays

Neutrinoless 3-prong tau lepton decays into a charged lepton and either two charged particles or one neutral meson have been searched for using 4.79 fb-1 of data collected with the CLEO II detector at Cornell Electron Storage Ring. This analysis represents an update of a previous study and the addition of six decay channels. In all channels the numbers of events found are compatible with background estimates and branching fraction upper limits are set for 28 different decay modes. These limits are either more stringent than those set previously or represent the first attempt to find these decays