4,018 research outputs found
Compact storage ring to search for the muon electric dipole moment
We present the concept of a compact storage ring of less than 0.5 m orbit
radius to search for the electric dipole moment of the muon () by
adapting the "frozen spin" method. At existing muon facilities a statistics
limited sensitivity of d_\mu \sim 5 \times 10^{-23} \ecm can be achieved
within one year of data taking. Reaching this precision would demonstrate the
viability of this novel technique to directly search for charged particle EDMs
and already test a number of Standard Model extensions. At a future, high-power
muon facility a statistical reach of d_\mu \sim 5 \times 10^{-25} \ecm seems
realistic with this setup.Comment: improved for submission; minor modification
An Overview of Centralised Middleware Components for Sensor Networks
Sensors are increasingly becoming part of our daily lives: motion detection, lighting control, environmental monitoring, and keeping track of energy consumption all rely on sensors. Combining data from this wide variety of sensors will result in new and innovative applications. However, access to these sensors – or the networks formed by them – is often provided via proprietary protocols and data formats, thereby obstructing the development of applications. To overcome such issues, middleware components have been employed to provide a universal interface to the sensor networks, hiding vendor-specific details from application developers. The scientific literature contains many descriptions of middleware components for sensor networks, with ideas from various fields of research. Recently, much attention in literature is aimed at what we, in this paper, define as ‘centralised’ middleware components. These components consider sensor networks that have no capacity – in terms of memory, data storage, and cpu power – to run middleware components (partially) on the sensor nodes. Often, viewed from the position of the middleware component, these sensor networks function as simple data providers for applications
In this paper we introduce the term ‘centralised’ for such middleware components, guided by a literature review of existing middleware components for sensor networks. We describe their general architecture, give a description of a representative set of four centralised middleware components, and discuss advantages and disadvantages of these components. Finally, we identify directions of further research that will impact centralised
middleware systems in the near future
Networks of Sensors - Operation and Control
Mei, R.D. van der [Promotor]Bhulai, S. [Copromotor
Erratum to:Study of ϒ production in pPb collisions at s NN = 8.16 TeV (Journal of High Energy Physics, (2018), 2018, 11, (194), 10.1007/JHEP11(2018)194)
In figure 11 of the original paper.</p
Observation of Several Sources of C P Violation in B + → π + π + π − Decays
Observations are reported of different sources of CP violation from an amplitude analysis of B+→π+π+π− decays, based on a data sample corresponding to an integrated luminosity of 3 fb−1 of pp collisions recorded with the LHCb detector. A large CP asymmetry is observed in the decay amplitude involving the tensor f2(1270) resonance, and in addition significant CP violation is found in the π+π−S wave at low invariant mass. The presence of CP violation related to interference between the π+π−S wave and the P wave B+→ρ(770)0π+ amplitude is also established; this causes large local asymmetries but cancels when integrated over the phase space of the decay. The results provide both qualitative and quantitative new insights into CP -violation effects in hadronic B decays
A search for Ξ++cc→ D+pK−π+ decays
A search for the Ξ++ccΞcc++ baryon through the Ξ++ccΞcc++→ D+pK−π+ decay is performed with a data sample corresponding to an integrated luminosity of 1.7 fb−1 recorded by the LHCb experiment in pp collisions at a centre-of-mass energy of 13 TeV. No significant signal is observed in the mass range from the kinematic threshold of the decay to 3800 MeV/c2. An upper limit is set on the ratio of branching fractions R=B(Ξ++cc→D+pK−π+)B(Ξ++cc→Λ+cK−π+π+)R=B(Ξcc++→D+pK−π+)B(Ξcc++→Λc+K−π+π+) with ℛ < 1.7 (2.1) × 10−2 at the 90% (95%) confidence level at the known mass of the Ξ++ccΞcc++ state
First Observation of the Doubly Charmed Baryon Decay Ξ + + c c → Ξ + c π +
The doubly charmed baryon decay Ξ++cc→Ξ+cπ+ is observed for the first time, with a statistical significance of 5.9σ, confirming a recent observation of the baryon in the Λ+cK−π+π+ final state. The data sample used corresponds to an integrated luminosity of 1.7 fb−1, collected by the LHCb experiment in pp collisions at a center-of-mass energy of 13 TeV. The Ξ++cc mass is measured to be 3620.6±1.5(stat)±0.4(syst)±0.3(Ξ+c) MeV/c2 and is consistent with the previous result. The ratio of branching fractions between the decay modes is measured to be[B(Ξ++cc→Ξ+cπ+)×B(Ξ+c→pK−π+)]/[B(Ξ++cc→Λ+cK−π+π+)×B(Λ+c→pK−π+)]=0.035±0.009(stat)±0.003(syst
Amplitude Analysis of B ± → π ± K + K − Decays
The first amplitude analysis of the B±→π±K+K− decay is reported based on a data sample corresponding to an integrated luminosity of 3.0 fb−1 of pp collisions recorded in 2011 and 2012 with the LHCb detector. The data are found to be best described by a coherent sum of five resonant structures plus a nonresonant component and a contribution from ππ↔KK S-wave rescattering. The dominant contributions in the π± K∓ and K+ K− systems are the nonresonant and the B±→ρ(1450)0π± amplitudes, respectively, with fit fractions around 30%. For the rescattering contribution, a sizable fit fraction is observed. This component has the largest CP asymmetry reported to date for a single amplitude of (−66±4±2)%, where the first uncertainty is statistical and the second systematic. No significant CP violation is observed in the other contributions
Measurement of Charged Hadron Production in Z -Tagged Jets in Proton-Proton Collisions at √ s = 8 TeV
The production of charged hadrons within jets recoiling against a Z boson is measured in proton-proton collision data at √s=8 TeV recorded by the LHCb experiment. The charged-hadron structure of the jet is studied longitudinally and transverse to the jet axis for jets with transverse momentum pT>20 GeV and in the pseudorapidity range 2.5<η<4. These are the first measurements of jet hadronization at these forward rapidities and also the first where the jet is produced in association with a Z boson. In contrast to previous hadronization measurements at the Large Hadron Collider, which are dominated by gluon jets, these measurements probe predominantly light-quark jets which are found to be more longitudinally and transversely collimated with respect to the jet axis when compared to the previous gluon dominated measurements. Therefore, these results provide valuable information on differences between quarks and gluons regarding nonperturbative hadronization dynamics
Measurement of the Ratio of the B-0 -> D*(-)iota(+)v(iota) and B-0 -> D*(-) mu(+)v(mu) Branching Fractions Using Three-Prong tau-Lepton Decays
The ratio of branching fractions R(D*(-)) equivalent to B(B-0 -> D*(-) iota(+)v(iota))/B(B-0 -> D*(-) mu+ v(mu)) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb(-1). For the first time, R(D*-) is determined using the iota-lepton decays with three charged pions in the final state. The B-0 -> D*(-) iota+ v(iota) yield is normalized to that of the B-0 -> D*(-) pi(+) pi(-) pi(+) mode, providing a measurement B-0 -> D*(-) iota+ v(iota) / B(B-0 -> D*(-) pi(+) pi(-) pi(+)) = 1.97 +/- 0.13 +/- 0.18, where the first uncertainty is statistical and the second systematic. The value of (B-0 -> D*(-) iota+ v(iota)) = (1.42 +/- 0.094 +/- 0.129 +/- 0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B-0 -> D*(-) mu+ v(mu) decay, a value of R(D*(-)) = 0.291 +/- 0.019 +/- 0.026 +/- 0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B-0 -> D*(-) mu+ v(mu) modes. This measurement is in agreement with the standard model prediction and with previous results
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