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Comparison of Monte Carlo generator predictions from Powheg and Sherpa to ATLAS measurements of top pair production at 7 TeV
https://cds.cern.ch/record/2018208
This note summarizes some of the latest Monte Carlo generator studies using ttbar events in ATLAS. Variations of the h_damp parameters and PDFs in the Powheg+Pythia8 setup are compared to ATLAS measurements of ttbar production. In addition, Powheg+Pythia6, Powheg+Herwig++ and Sherpa MEPS@NLO are also compared to the same measurements.The ATLAS collaborationMon, 25 May 2015 15:58:20 GMT25 May 2015ATL-PHYS-PUB-2015-010https://cds.cern.ch/record/2018208The LUCID detector
https://cds.cern.ch/record/2018182
Starting from 2015 LHC will perform a new run, at higher center of mass energy (13 TeV) and with 25 ns bunch-spacing. The ATLAS luminosity monitor LUCID has been completely renewed, both on detector design and in the electronics, in order to cope with the new running conditions. The new detector electronics is presented, featuring a new read-out board (LUCROD), for signal acquisition and digitization, PMT-charge integration and single-side luminosity measurements, and the revisited LUMAT board for side A–side C combination. The contribution covers the new boards design, the firmware and software developments, the implementation of luminosity algorithms, the optical communication between boards and the integration into the ATLAS TDAQ system.Lasagni Manghi, FedericoThe ATLAS collaborationATLAS LUCID CollaborationMon, 25 May 2015 08:20:43 GMT25 May 2015ATL-FWD-SLIDE-2015-270https://cds.cern.ch/record/2018182Comparison of the Z$/\gamma^{*}$+jets to $\gamma$+jets cross sections in pp collisions at $\sqrt{s} =$ 8 TeV
https://cds.cern.ch/record/2018180
A comparison of the differential cross sections for the processes Z$/\gamma^{*}$+jets and photon ($\gamma$)+jets is presented. The measurements are based on data collected with the CMS detector at $\sqrt{s} =$ 8 TeV corresponding to an integrated luminosity of 19.7 fb$^{-1}$. The differential cross sections and their ratios are presented as functions of $ p_{ \mathrm{T} } $. The measurements are also shown as functions of the jet multiplicity. Differential cross sections are obtained as functions of the ratio of the Z$/\gamma^{*}$ $ p_{ \mathrm{T} } $ to the sum of all jet transverse momenta and of the ratio of the Z$/\gamma^{*}$ $ p_{ \mathrm{T} } $ to the leading jet transverse momentum. The data are corrected for detector effects and are compared to simulations based on several QCD calculations.CMS CollaborationMon, 25 May 2015 07:34:28 GMT25 May 2015CERN-PH-EP-2015-089https://cds.cern.ch/record/2018180Thermometry and cooling of a Bose-Einstein condensate to 0.02 times the critical temperature
https://cds.cern.ch/record/2018179
Ultracold gases promise access to many-body quantum phenomena at convenient length and time scales. However, it is unclear whether the entropy of these gases is low enough to realize many phenomena relevant to condensed matter physics, such as quantum magnetism. Here we report reliable single-shot temperature measurements of a degenerate $^{87}$Rb gas by imaging the momentum distribution of thermalized magnons, which are spin excitations of the atomic gas. We record average temperatures as low as $0.022(1)_\text{stat}(2)_\text{sys}$ times the Bose-Einstein condensation temperature, indicating an entropy per particle, $S/N\approx0.001\, k_B$ at equilibrium, that is well below the critical entropy for antiferromagnetic ordering of a Bose-Hubbard system. The magnons themselves can reduce the temperature of the system by absorbing energy during thermalization and by enhancing evaporative cooling, allowing low-entropy gases to be produced within deep traps.Olf, RyanFang, FangMarti, G EdwardMacRae, AndrewStamper-Kurn, Dan MMon, 25 May 2015 05:26:20 GMT22 May 2015arXiv:1505.06196https://cds.cern.ch/record/2018179Drawing the Free Rigid Body Dynamics According to Jacobi
https://cds.cern.ch/record/2018178
Guided by the Jacobi's work published the year before his death about the rotation of a rigid body, the behavior of the rotation matrix describing the dynamics of the free rigid body is studied. To illustrate this dynamics one draws on a unit sphere the trace of the three unit vectors, in the body system along the principal directions of inertia. A minimal set of properties of Jacobi's elliptic functions are used, those which allow to compute with the necessary precision the dynamics of the rigid body without torques, the so called Euler's top. Emphasis is on the paper published by Jacobi in 1850 on the explicit expression for the components of the rotation matrix. The tool used to compute the trajectories to be drawn are the Jacobi's Fourier series for {\sl theta} and {\sl eta} functions with extremely fast convergence. The Jacobi's {\sl sn}, {\sl cn} and {\sl dn} functions, which are better known, are used also as ratios of {\sl theta} functions which permit quick and accurate computation. Finally the main periodic part of the herpolhode curve was computed and graphically represented.Pina, Eduardo GMon, 25 May 2015 05:26:20 GMT03 May 2015arXiv:1505.06186https://cds.cern.ch/record/2018178Collapsing Plane Symmetric Source with Heat Flux and Conformal Flatness
https://cds.cern.ch/record/2018177
This paper deals with the study of collapsing plane symmetric source in the presence of heat flux. For this purpose, we have calculated the Einstein field equations as well as Weyl tensor components. The conditions for the conformal flatness have been determined. The interior source has been matched smoothly with the exterior geometry in single null coordinate. It has been found the pressure is balanced with the out going heat flux and the continuity of the masses in two regions has been noted. A simple new model of collapse has been proposed which satisfies flatness condition, also we have discussed the physical properties of the model. For our model, we have calculated the temperature profile by using the approximation scheme.Abbas, GAhmad, ZahidShah, HassanMon, 25 May 2015 05:26:20 GMT24 Apr 2015arXiv:1505.06185https://cds.cern.ch/record/2018177Ferrell-Berreman modes in plasmonic epsilon-near-zero media
https://cds.cern.ch/record/2018176
We observe unique absorption resonances in silver/silica multilayer-based epsilon-near-zero (ENZ) metamaterials that are related to radiative bulk plasmon-polariton states of thin-films originally studied by Ferrell (1958) and Berreman (1963). In the local effective medium, metamaterial descrip- tion, the unique effect of the excitation of these microscopic modes is counterintuitive and captured within the complex propagation constant, not the effective dielectric permittivities. Theoretical anal- ysis of the band structure for our metamaterials shows the existence of multiple Ferrell-Berreman branches with slow light characteristics. The demonstration that the propagation constant reveals subtle microscopic resonances can lead to the design of devices where Ferrell-Berreman modes can be exploited for practical applications ranging from plasmonic sensing to imaging and absorption enhancement.Newman, Ward DCortes, Cristian LAtkinson, JonPramanik, SandipanDeCorby, Raymond GJacob, ZubinMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06180https://cds.cern.ch/record/2018176Analysis of Kolmogorov Flow and Rayleigh-B\'enard Convection using Persistent Homology
https://cds.cern.ch/record/2018175
We use persistent homology to build a quantitative understanding of large complex systems that are driven far-from-equilibrium; in particular, we analyze image time series of flow field patterns from numerical simulations of two important problems in fluid dynamics: Kolmogorov flow and Rayleigh-B\'enard convection. For each image we compute a persistence diagram to yield a reduced description of the flow field; by applying different metrics to the space of persistence diagrams, we relate characteristic features in persistence diagrams to the geometry of the corresponding flow patterns. We also examine the dynamics of the flow patterns by a second application of persistent homology to the time series of persistence diagrams. We demonstrate that persistent homology provides an effective method both for quotienting out symmetries in families of solutions and for identifying multiscale recurrent dynamics. Our approach is quite general and it is anticipated to be applicable to a broad range of open problems exhibiting complex spatio-temporal behavior.Kramar, MiroslavLevanger, RachelTithof, JeffreySuri, BalachandraXu, MuPaul, MarkSchatz, Michael FMischaikow, KonstantinMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06168https://cds.cern.ch/record/2018175Interfacing transitions of different alkali atoms and telecom bands using one narrowband photon pair source
https://cds.cern.ch/record/2018174
Photon-atom coupling, in particular for proposed quantum repeater schemes, requires pure and versatile sources of quantum light. Here we demonstrate coupling to alkali dipole transitions in the near-infrared with a tunable source of photon pairs generated via spontaneous parametric down-conversion in a whispering-gallery mode resonator (WGMR). We have developed novel wavelength tuning mechanisms, which allow for a coarse step-wise central wavelength tuning from 790 nm to 1630 nm as well as continuous tuning with MHz resolution. We demonstrate the compatibility of our source with atomic transitions, such as the D1 line of rubidium at 795 nm (idler at 1608 nm) and cesium at 895\,nm (idler at 1312 nm). At the cesium D1 transition, we exemplarily show a continuous scanning of the signal wavelength over the Doppler-broadened absorption line, and finally a heralded single photon spectroscopy of the atomic decay. Providing this flexibility in connecting various atomic transitions with telecom wavelengths, we demonstrate a compact tool for interfacing quantum memories and realizing essential building blocks for quantum repeaters.Schunk, GerhardVogl, UlrichStrekalov, Dmitry VFörtsch, MichaelSedlmeir, FlorianSchwefel, Harald G LGöbelt, ManuelaChristiansen, SilkeLeuchs, GerdMarquardt, ChristophMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06141https://cds.cern.ch/record/2018174Ionization of Cucurbiturils as a Pathway to More Stable Host-Guest Complexes
https://cds.cern.ch/record/2018173
Cucurbiturils are particularly interesting to chemists, because these macrocyclic molecules are suitable hosts for an array of neutral and cationic species. It is believed that the host-guest binding originated from hydrophobic interactions and ion-dipole interactions in the case of cationic guests. The fact that an elementary unit of cucurbiturils consists of two fused imidazole rings, which ionize readily, has remained largely unnoticed up to now. This work reports ionized cucurbiturils and their binding to C60 fullerene using versatile electronic-precision description. The methodology is based on density functional theory. We assert that cationization of cucurbiturils fosters C60-cucurbituril binding due to polarization of electron density in C60. Therefore, more stable host-guest complexes can be derived.Chaban, Vitaly VFileti, Eudes EternoMalaspina, ThacianaMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06140https://cds.cern.ch/record/2018173Active cloaking of resonant coated inclusions for waves in membranes and Kirchhoff plates
https://cds.cern.ch/record/2018172
The dynamic response of a coated inclusion is considered in the context of active cloaking. The active cloak is achieved for a coated inclusion in the presence of membrane and flexural waves. In this paper, we investigate the design of an active cloak for a coated inclusion in three frequency regimes: the very low frequency (monopole dominated) range, the intermediate range, and the higher frequency range in which scattering resonances occur. In the first of these ranges, we validate previous work, which resulted in a simple mass-compensation design for the monopole scatterer, while in the second and third ranges, a combination of the use of an appropriate coating and the appropriate choice of the amplitudes of the active cloaking sources is necessary. We show that such cloaking can indeed be effective in the region of strong scattering resonances. We give closed form analytic expressions for the required amplitudes of the active cloaking sources in the three frequency regions and provide asymptotic estimates and numerical illustrations.O'Neill, JSelsil, OMcPhedran, R CMovchan, A BMovchan, N VMoggach, C HendersonMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06138https://cds.cern.ch/record/2018172General formulation of Luria-Delbr{\"u}ck distribution of the number of mutants
https://cds.cern.ch/record/2018171
The Luria-Delbr{\"u}ck experiment is a cornerstone of evolutionary theory, demonstrating the ran-domness of mutations before selection. The distribution of the number of mutants in this experiment has been the subject of intense investigation during the last 70 years. Despite this considerable effort, most of the results have been obtained under the assumption of constant growth rate, which is far from the experimental condition. We derive here the properties of this distribution for arbitrary growth function, for both the deterministic and stochastic growth of the mutants. The derivation we propose is surprisingly simple and versatile, allowing many generalizations to be taken easily into account.Houchmandzadeh, BahramMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06108https://cds.cern.ch/record/2018171Fast and efficient transport of large ion clouds
https://cds.cern.ch/record/2018170
The manipulation of trapped charged particles by electric fields is an accurate, robust and reliable technique for many applications or experiments in high-precision spectroscopy. The transfer of the ion sample between multiple traps allows the use of a tailored environment in quantum information, cold chemistry, or frequency metrology experiments. In this article, we experimentally study the transport of ion clouds of up to 50 000 ions. The design of the trap makes ions very sensitive to any mismatch between the assumed electric potential and the actual local one. Nevertheless, we show that being fast (100 $\mu$s to transfer over more than 20 mm) increases the transport efficiency to values higher than 90 %, even with a large number of ions. For clouds of less than 2000 ions, a 100 % transfer efficiency is observed.Kamsap, Marius RomualdPedregosa-Gutierrez, JofreChampenois, CarolineGuyomarc'H, DidierHoussin, MarieKnoop, MartinaMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06104https://cds.cern.ch/record/2018170Stabilising nontrivial solutions of the generalised Kuramoto-Sivashinsky equation using feedback and optimal control
https://cds.cern.ch/record/2018169
The problem of controlling and stabilising solutions to the Kuramoto-Sivashinsky equation is studied in this paper. We consider a generalised form of the equation in which the effects of an electric field and dispersion are included. Both the feedback and optimal control problems are studied. We prove that we can control arbitrary nontrivial steady states of the Kuramoto-Sivashinsky equation, including travelling wave solutions, using a finite number of point actuators. The number of point actuators needed is related to the number of unstable modes of the equation. Furthermore, the proposed control methodology is shown to be robust with respect to changing the parameters in the equation, e.g. the viscosity coefficient or the intensity of the electric field. We also study the problem of controlling solutions of coupled systems of Kuramoto-Sivashinsky equations. Possible applications to controlling thin film flows are discussed. Our rigorous results are supported by extensive numerical simulations.Gomes, Susana NPapageorgiou, Demetrios TPavliotis, Grigorios AMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06086https://cds.cern.ch/record/2018169Spatiotemporal characterization of ultrashort optical vortex pulses
https://cds.cern.ch/record/2018168
Generation of few-cycle optical vortex pulses is challenging due to the large spectral bandwidths, as most vortex generation techniques are designed for monochromatic light. In this work, we use a spiral phase plate to generate few-cycle optical vortices from an ultrafast titanium:sapphire oscillator, and characterize them in the spatiotemporal domain using a recently introduced technique based on spatially resolved Fourier transform spectrometry. The performance of this simple approach to the generation of optical vortices is analyzed from a wavelength dependent perspective, as well as in the spatiotemporal domain, allowing us to completely characterize ultrashort vortex pulses in space, frequency, and time.Miranda, MiguelKotur, MarijaRudawski, PiotrGuo, ChenHarth, AnneL'Huillier, AnneArnold, Cord LMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06081https://cds.cern.ch/record/2018168Probing Atomic Structure and Majorana Wavefunctions in Mono-Atomic Fe-chains on Superconducting Pb-Surface
https://cds.cern.ch/record/2018167
Motivated by the striking promise of quantum computation, Majorana bound states (MBSs) in solid-state systems have attracted wide attention in recent years. In particular, the wavefunction localization of MBSs is a key feature and crucial for their future implementation as qubits. Here, we investigate the spatial and electronic characteristics of topological superconducting chains of iron atoms on the surface of Pb(110) by combining scanning tunneling microscopy (STM) and atomic force microscopy (AFM). We demonstrate that the Fe chains are mono-atomic, structured in a linear fashion, and exhibit zero-bias conductance peaks at their ends which we interprete as signature for a Majorana bound state. Spatially resolved conductance maps of the atomic chains reveal that the MBSs are well localized at the chain ends (below 25 nm), with two localization lengths as predicted by theory. Our observation lends strong support to use MBSs in Fe chains as qubits for quantum computing devices.Pawlak, RemyKisiel, MarcinKlinovaja, JelenaMeier, TobiasKawai, ShigekiGlatzel, ThiloLoss, DanielMeyer, ErnstMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06078https://cds.cern.ch/record/2018167Hamiltonian integration methods for Vlasov-Maxwell equations
https://cds.cern.ch/record/2018166
Hamiltonian integration methods for the Vlasov-Maxwell equations are developed by a Hamiltonian splitting technique. The Hamiltonian functional is split into five parts, i.e., the electrical energy, the magnetic energy, and the kinetic energy in three Cartesian components. Each of the subsystems is a Hamiltonian system with respect to the Morrison-Marsden-Weinstein Poisson bracket and can be solved exactly. Compositions of the exact solutions yield Poisson structure preserving, or Hamiltonian, integration methods for the Vlasov-Maxwell equations, which have superior long-term fidelity and accuracy.He, YangQin, HongSun, YajuanXiao, JianyuanZhang, RuiliLiu, JianMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06076https://cds.cern.ch/record/2018166Observation of a New Type of Low Frequency Waves at Comet 67P/Churyumov-Gerasimenko
https://cds.cern.ch/record/2018165
We report on magnetic field measurements made in the innermost coma of 67P/Churyumov-Gerasimenko in its low activity state. Quasi-coherent, large-amplitude ($\delta B/B \sim 2$), compressional magnetic field oscillations at $\sim$ 40 mHz dominate the immediate plasma environment of the nucleus. This differs from previously studied comet-interaction regions where waves at the cometary ion gyro-frequencies are the main feature. Thus classical pick-up ion driven instabilities are unable to explain the observations. We propose a cross-field current instability associated with newborn cometary ion currents as a possible source mechanism.Richter, IKoenders, CAuster, H -UFruehauff, DGoetz, CHeinisch, PPerschke, CMotschmann, UStoll, BAltwegg, KBurch, JCarr, CCupido, EEriksson, AHenri, PGoldstein, RLebreton, J -PMokashi, PNemeth, ZNilsson, HRubin, MSzegoe, KTsurutani, B TVallat, CVolwerk, MGlassmeier, K -HMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06068https://cds.cern.ch/record/2018165The effect of ionic diffusion on extracellular potentials in neural tissue
https://cds.cern.ch/record/2018164
In computational neuroscience, it is common to use the simplifying assumption that diffusive currents are negligible compared to Ohmic currents. However, endured periods of intense neural signaling may cause local ion concentration changes in the millimolar range. Theoretical studies have identified scenarios where steep concentration gradients give rise to diffusive currents that are of comparable magnitude with Ohmic currents, and where the simplifying assumption that diffusion can be neglected does not hold. We here propose a novel formalism for computing (1) the ion concentration dynamics and (2) the electrical potential in the extracellular space surrounding multi-compartmental neuron models or networks of such (e.g., the Blue-Brain simulator). We use this formalism to explore the effects that diffusive currents can have on the extracellular (ECS) potential surrounding a small population of active cortical neurons. Our key findings are: (i) Sustained periods of neuronal output (simulations were run for 84 s) could change local ECS ion concentrations by several mM, as observed experimentally. (ii) For large, but realistic, concentration gradients, diffusive currents in the ECS were of the same magnitude as Ohmic currents. (iii) Neuronal current sources could induce local changes in the ECS potential by a few mV, whereas diffusive currents could could induce local changes in the ECS potential by a few tens of a mV. Diffusive currents could thus have a quite significant impact on ECS potentials. (v) Potential variations caused by diffusive currents were quite slow, but could influence the comparable to those induced by Ohmic currents up to frequencies as high as 7Hz.Halnes, GeirMäki-Marttunen, TuomoKeller, DanielPettersen, Klas HEivenoll, Gaute TMon, 25 May 2015 05:26:19 GMT22 May 2015arXiv:1505.06033https://cds.cern.ch/record/2018164Distinct types of eigenvector localization in networks
https://cds.cern.ch/record/2018163
The spectral properties of the adjacency matrix provide a trove of information about the structure and function of complex networks. In particular, the largest eigenvalue and its associated principal eigenvector are crucial in the understanding of node's centrality and the unfolding of dynamical processes. Here we show that two distinct types of localization of the principal eigenvector may occur in heterogeneous networks. For synthetic networks with degree distribution $P(q) \sim q^{-\gamma}$, localization occurs on the largest hub if $\gamma>5/2$; for $\gamma<5/2$ a new type of localization arises on a mesoscopic subgraph associated to the shell with the largest index in the $K$-core decomposition. Similar evidence for the existence of distinct localization modes is found in the analysis of real-world networks. Our results open a new perspective on dynamical processes on networks and on a recently proposed alternative measure of node centrality based on the non-backtracking matrix.Pastor-Satorras, RomualdoCastellano, ClaudioMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.06024https://cds.cern.ch/record/2018163Two universal physical principles shape the power-law statistics of real-world networks
https://cds.cern.ch/record/2018162
The study of complex networks has pursued an understanding of macroscopic behavior by focusing on power-laws in microscopic observables. Here, we uncover two universal fundamental physical principles that are at the basis of complex networks generation. These principles together predict the generic emergence of deviations from ideal power laws, which were previously discussed away by reference to the thermodynamic limit. Our approach proposes a paradigm shift in the physics of complex networks, toward the use of power-law deviations to infer meso-scale structure from macroscopic observations.Lorimer, TomGomez, FlorianStoop, RuediMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.06005https://cds.cern.ch/record/2018162Divergence of optical vortex beams
https://cds.cern.ch/record/2018161
We show, both theoretically and experimentally, that the propagation of optical vortices in free space can be analysed by using the width ($w(z)$) of the host Gaussian beam and the inner and outer radii of the vortex beam at the source plane ($z=0$) as defined in \textit{Optics Letters \textbf{39,} 4364-4367 (2014)}. We also studied the divergence of vortex beams, considered as the rate of change of inner or outer radius with the propagation distance, and found that it varies with the order in the same way as that of the inner and outer radii at zero propagation distance. These results may be useful in designing optical fibers for orbital angular momentum modes that play a crucial role in quantum communication.Reddy, Salla GangiP, ChithrabhanuPrabhakar, ShashiAnwar, AliBanerji, JSingh, R PMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.05993https://cds.cern.ch/record/2018161Broadband black phosphorus optical modulator in visible to mid-infrared spectral range
https://cds.cern.ch/record/2018160
Black phosphorous (BP), a two-dimensional (2D) material, has a direct bandgap, which fills up the bandgap lacuna left by graphene topological insulators and transition-metal dichalcogenides because of its dependence on the layers and applied strains. Theoretically, the direct and tunable band gap indicates the broadband applications in optoelectronics with high efficiencies in the spectral range from visible to mid-infrared. Here, a BP broadband optical modulator is experimentally constructed and the passively modulated lasers at 639 nm (red), 1.06 um (near-infrared) and 2.1 um (mid-infrared) are realized by using the BP optical modulator as the saturable absorber in bulk lasers. The obtained results provide a promising alternative for rare broadband optical modulators and broaden the application range of BP in photonics.Zhang, RuiZhang, YuxiaYu, HaohaiZhang, HuaijinYang, RuinongYang, BingchaoLiu, ZhongyuanWang, JiyangMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.05992https://cds.cern.ch/record/2018160The Limiting Speed of the Bacterial Flagellar Motor
https://cds.cern.ch/record/2018159
Recent experiments on the bacterial flagellar motor have shown that the structure of this nanomachine, which drives locomotion in a wide range of bacterial species, is more dynamic than previously believed. Specifically, the number of active torque-generating units (stators) was shown to vary across applied loads. This finding invalidates the experimental evidence reporting that limiting (zero-torque) speed is independent of the number of active stators. Here, we propose that, contrary to previous assumptions, the maximum speed of the motor is not universal, but rather increases as additional torque-generators are recruited. This result arises from our assumption that stators disengage from the motor for a significant portion of their mechanochemical cycles at low loads. We show that this assumption is consistent with current experimental evidence and consolidate our predictions with arguments that a processive motor must have a high duty ratio at high loads.Nirody, Jasmine ABerry, Richard MOster, GeorgeMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.05966https://cds.cern.ch/record/2018159Transient eddy current flow metering
https://cds.cern.ch/record/2018158
Measuring local velocities or entire flow rates in liquid metals or semiconductor melts is a notorious problem in many industrial applications, including metal casting and silicon crystal growth. We present a new variant of an old technique which relies on the continuous tracking of a flow-advected transient eddy current that is induced by a pulsed external magnetic field. This calibration-free method is validated by applying it to the velocity of a spinning disk made of aluminum. First tests at a rig with a flow of liquid GaInSn are also presented.Forbriger, JanStefani, FrankMon, 25 May 2015 05:26:18 GMT22 May 2015arXiv:1505.05959https://cds.cern.ch/record/2018158