2,840 research outputs found

    Upper bounds of dual flagged Weyl characters

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    For a subset DD of boxes in an n×nn\times n square grid, let χD(x)\chi_{D}(x) denote the dual character of the flagged Weyl module associated to DD. It is known that χD(x)\chi_{D}(x) specifies to a Schubert polynomial (resp., a key polynomial) in the case when DD is the Rothe diagram of a permutation (resp., the skyline diagram of a composition). One can naturally define a lower and an upper bound of χD(x)\chi_{D}(x). M{\'e}sz{\'a}ros, St. Dizier and Tanjaya conjectured that χD(x)\chi_{D}(x) attains the upper bound if and only if DD avoids a certain subdiagram. We provide a proof of this conjecture

    Are the Clast Lithologies Contained in Lunar Breccia 64435 Mixtures of Anorthositic Magmas

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    The anorthositic crust of the Moon is often used as the archtypical example of a primary planetary crust. The abundance and purity of anorthosite in the Apollo sample collection and remote sensing data are generally attributed to an early global magma ocean which produced widespread floating plagioclase cumulates (the ferroan anorthosites; FANs. Recent geochronology studies report evidence of young (less than 4.4 Ga) FAN ages, which suggest that either some may not be directly produced from the magma ocean or that the final solidification age of the magma ocean was younger than previous estimates. A greater diversity of anorthositic rocks have been identified among lunar meteorites as compared to returned lunar samples. Granted that these lithologies are often based on small clasts in lunar breccias and therefore may not represent their actual whole rock composition. Nevertheless, as suggested by the abundance of anorthositic clasts with Mg# [Mg/(Mg+Fe)] less than 0.80 and the difficulty of producing the extremely high plagioclase contents observed in Apollo samples and the remote sensing data, modification of the standard Lunar Magma Ocean (LMO) model may be in order. To ground truth mission science and to further test the LMO and other hypotheses for the formation of the lunar crust, additional coordinated petrology and geochronology studies of lunar anorthosites would be informative. Here we report new mineral chemistry and trace element geochemistry studies of thick sections of a composite of FAN-suite igneous clasts contained in the lunar breccia 64435 in order to assess the significance of this type of sample for petrogenetic studies of the Moon. This work follows recent isotopic studies of the lithologies in 64435 focusing on the same sample materials and expands on previous petrology studies who identified three lithologies in this sample and worked on thin sections

    Networking - A Statistical Physics Perspective

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    Efficient networking has a substantial economic and societal impact in a broad range of areas including transportation systems, wired and wireless communications and a range of Internet applications. As transportation and communication networks become increasingly more complex, the ever increasing demand for congestion control, higher traffic capacity, quality of service, robustness and reduced energy consumption require new tools and methods to meet these conflicting requirements. The new methodology should serve for gaining better understanding of the properties of networking systems at the macroscopic level, as well as for the development of new principled optimization and management algorithms at the microscopic level. Methods of statistical physics seem best placed to provide new approaches as they have been developed specifically to deal with non-linear large scale systems. This paper aims at presenting an overview of tools and methods that have been developed within the statistical physics community and that can be readily applied to address the emerging problems in networking. These include diffusion processes, methods from disordered systems and polymer physics, probabilistic inference, which have direct relevance to network routing, file and frequency distribution, the exploration of network structures and vulnerability, and various other practical networking applications.Comment: (Review article) 71 pages, 14 figure

    Experimental demonstration of a BDCZ quantum repeater node

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    Quantum communication is a method that offers efficient and secure ways for the exchange of information in a network. Large-scale quantum communication (of the order of 100 km) has been achieved; however, serious problems occur beyond this distance scale, mainly due to inevitable photon loss in the transmission channel. Quantum communication eventually fails when the probability of a dark count in the photon detectors becomes comparable to the probability that a photon is correctly detected. To overcome this problem, Briegel, D\"{u}r, Cirac and Zoller (BDCZ) introduced the concept of quantum repeaters, combining entanglement swapping and quantum memory to efficiently extend the achievable distances. Although entanglement swapping has been experimentally demonstrated, the implementation of BDCZ quantum repeaters has proved challenging owing to the difficulty of integrating a quantum memory. Here we realize entanglement swapping with storage and retrieval of light, a building block of the BDCZ quantum repeater. We follow a scheme that incorporates the strategy of BDCZ with atomic quantum memories. Two atomic ensembles, each originally entangled with a single emitted photon, are projected into an entangled state by performing a joint Bell state measurement on the two single photons after they have passed through a 300-m fibre-based communication channel. The entanglement is stored in the atomic ensembles and later verified by converting the atomic excitations into photons. Our method is intrinsically phase insensitive and establishes the essential element needed to realize quantum repeaters with stationary atomic qubits as quantum memories and flying photonic qubits as quantum messengers.Comment: 5 pages, 4 figure

    First Observation of Radiative B^0 -> \phi K^0 \gamma Decays and Measurements of Their Time-Dependent CP Violation

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    We report the first observation of the radiative decay B^0 -> \phi K^0 \gamma using a data sample of 772 x 10^6 B B-bar pairs collected at the \Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. We observe a signal of 37+/-8 events with a significance of 5.4 standard deviations including systematic uncertainties. The measured branching fraction is B(B0−>ϕK0Îł)=(2.74±0.60±0.32)×10−6{\cal B}(B^0 -> \phi K^0 \gamma) = (2.74\pm 0.60 \pm 0.32) \times 10^{-6}, where the uncertainties are statistical and systematic, respectively. We also report the first measurements of time-dependent CP violation parameters: SϕKS0Îł=+0.74−1.05+0.72(stat)−0.24+0.10(syst){\mathcal S}_{\phi K_S^0 \gamma} = +0.74^{+0.72}_{-1.05} (stat)^{+0.10}_{-0.24} (syst) and AϕKS0Îł=+0.35+/−0.58(stat)−0.10+0.23(syst){\mathcal A}_{\phi K_S^0 \gamma} = +0.35 +/- 0.58 (stat)^{+0.23}_{-0.10} (syst). Furthermore, we measure B(B+−>ϕK+Îł)=(2.48+/−0.30+/−0.24)x10−6{\mathcal B}(B^+ -> \phi K^+ \gamma) = (2.48 +/- 0.30 +/- 0.24) x 10^{-6}, ACP=−0.03+/−0.11+/−0.08{\mathcal A}_{CP} = -0.03 +/- 0.11 +/- 0.08 and find that the signal is concentrated in the M_{\phi K} mass region near threshold.Comment: 6 pages, 3 figures, Modified version is to be published in PRD(RC

    Observation of D0−Dˉ0D^0-\bar{D}^0 Mixing in e+e−e^+e^- Collisions

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    We observe D0−Dˉ0D^0-\bar{D}^0 mixing in the decay D0→K+π−D^0\rightarrow K^+\pi^- using a data sample of integrated luminosity 976 fb−1^{-1} collected with the Belle detector at the KEKB e+e−e^+e^- asymmetric-energy collider. We measure the mixing parameters xâ€Č2=(0.09±0.22)×10−3{x'}^2 = (0.09\pm0.22)\times 10^{-3} and yâ€Č=(4.6±3.4)×10−3y' = (4.6\pm3.4)\times 10^{-3} and the ratio of doubly Cabibbo-suppressed to Cabibbo-favored decay rates RD=(3.53±0.13)×10−3R_D = (3.53\pm0.13)\times 10^{-3}, where the uncertainties are statistical and systematic combined. Our measurement excludes the no-mixing hypothesis at the 5.1 standard deviation level.Comment: 6 pages, 4 figure

    A randomised phase II study of weekly paclitaxel or vinorelbine in combination with cisplatin against inoperable non-small-cell lung cancer previously untreated

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    [[abstract]]Phase II studies have suggested that weekly paclitaxel has a higher response rate and better toxicity profile than the conventional schedule of once every 3 or 4 weeks. Our aim was to evaluate the efficacy of weekly paclitaxel plus cisplatin (PC) vs vinorelbine plus cisplatin (VC) in chemonaive non-small-cell lung cancer (NSCLC) patients. From October 2000 to May 2002, 140 patients were enrolled. The treatment dose was P 66 mg m(-2) intravenous infusion (im.) on days 1, 8, and 15, and C 60 mg m(-2) i.v. on day 15, or V 23 mg m(-2) i.V. on days 1, 8, and 15, and C 60 mg m(-2) i.v. on day 15, every 4 weeks. In all, 28 1 cycles of PC and 307 cycles of VC were given to the patients in the PC and VC arms, respectively. There were 26 partial responses and one complete response (overall 38.6%) in the PC arm, and no complete responses, but 27 partial responses (overall 38.6%) in the VC arm. Myelosuppression was more common in the VC arm (P<0.001). Peripheral neuropathy and myalgia were significantly more common in the PC arm (P<0.001). The median time to disease progression was 6 months in the PC arm and 8.4 months in the VC arm (P=0.0344). The median survival time was 11.7 months in the PC arm and 15.4 months in the VC arm (P = 0.297). We concluded that weekly PC is not suggested for NSCLC patients due to the relatively shorter progression-free survival and more common nonhaematological toxicities

    Angular analysis of B0→K∗(892)0ℓ+ℓ−B^0 \to K^\ast(892)^0 \ell^+ \ell^-

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    We present a measurement of angular observables, P4â€ČP_4', P5â€ČP_5', P6â€ČP_6', P8â€ČP_8', in the decay B0→K∗(892)0ℓ+ℓ−B^0 \to K^\ast(892)^0 \ell^+ \ell^-, where ℓ+ℓ−\ell^+\ell^- is either e+e−e^+e^- or ÎŒ+Ό−\mu^+\mu^-. The analysis is performed on a data sample corresponding to an integrated luminosity of 711 fb−1711~\mathrm{fb}^{-1} containing 772×106772\times 10^{6} BBˉB\bar B pairs, collected at the ΄(4S)\Upsilon(4S) resonance with the Belle detector at the asymmetric-energy e+e−e^+e^- collider KEKB. Four angular observables, P4,5,6,8â€ČP_{4,5,6,8}' are extracted in five bins of the invariant mass squared of the lepton system, q2q^2. We compare our results for P4,5,6,8â€ČP_{4,5,6,8}' with Standard Model predictions including the q2q^2 region in which the LHCb collaboration reported the so-called P5â€ČP_5' anomaly.Comment: Conference paper for LHC Ski 2016. SM prediction for P6â€ČP_{6}' corrected and reference for arXiv:1207.2753 adde
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