2,915 research outputs found

    The use of quantum-correlated D^0 decays for phi3 measurement

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    We report the results of the Monte-Carlo study of the method to determine the CKM angle phi3 using Dalitz plot analysis of D0 decay from B->DK process. Our main goal is to find the optimal strategy for a model-independent phi3 extraction. We find that the analysis using decays of CP-tagged D mesons only cannot provide a completely model-independent measurement in the case of limited data sample. The procedure involving binned analysis of B->DK and psi(3770)->(K0 pi+ pi-)_D (K0 pi+ pi-)_D decays is proposed, that allows to reach the phi3 precision comparable to unbinned model-dependent fit.Comment: Replaced by journal versio

    Effect of FCNC mediated Z boson on lepton flavor violating decays

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    We study the three body lepton flavor violating (LFV) decays μee+e\mu^- \to e^- e^+ e^-, τlilj+lj\tau^- \to l_i^- l_j^+ l_j^- and the semileptonic decay τμϕ\tau \to \mu \phi in the flavor changing neutral current (FCNC) mediated ZZ boson model. We also calculate the branching ratios for LFV leptonic B decays, Bd,sμeB_{d,s} \to \mu e, Bd,sτeB_{d,s} \to \tau e, Bd,sτμB_{d,s} \to \tau \mu and the conversion of muon to electron in Ti nucleus. The new physics parameter space is constrained by using the experimental limits on μee+e\mu^- \to e^- e^+ e^- and τμμ+μ\tau^- \to \mu^- \mu^+ \mu^-. We find that the branching ratios for τeee\tau \to eee and τμϕ\tau \to \mu \phi processes could be as large as O(108)\sim {\cal O}(10^{-8}) and BrBd,sτμ,τe)O(1010){\rm Br}B_{d,s} \to \tau \mu, \tau e) \sim {\cal O}(10^{-10}). For other LFV B decays the branching ratios are found to be too small to be observed in the near future.Comment: 15 pages, 8 figures, typos corrected, one more section added, version to appear in EPJ

    Agile SoC Development with Open ESP

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    ESP is an open-source research platform for heterogeneous SoC design. The platform combines a modular tile-based architecture with a variety of application-oriented flows for the design and optimization of accelerators. The ESP architecture is highly scalable and strikes a balance between regularity and specialization. The companion methodology raises the level of abstraction to system-level design and enables an automated flow from software and hardware development to full-system prototyping on FPGA. For application developers, ESP offers domain-specific automated solutions to synthesize new accelerators for their software and to map complex workloads onto the SoC architecture. For hardware engineers, ESP offers automated solutions to integrate their accelerator designs into the complete SoC. Conceived as a heterogeneous integration platform and tested through years of teaching at Columbia University, ESP supports the open-source hardware community by providing a flexible platform for agile SoC development.Comment: Invited Paper at the 2020 International Conference On Computer Aided Design (ICCAD) - Special Session on Opensource Tools and Platforms for Agile Development of Specialized Architecture

    Multifractal Behaviour of n-Simplex Lattice

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    We study the asymptotic behaviour of resistance scaling and fluctuation of resistance that give rise to flicker noise in an {\em n}-simplex lattice. We propose a simple method to calculate the resistance scaling and give a closed-form formula to calculate the exponent, βL\beta_L, associated with resistance scaling, for any n. Using current cumulant method we calculate the exact noise exponent for n-simplex lattices.Comment: Latex, 9 pages including one figur

    CP Violation in \tau ->\nu\pi K_S and D->\pi K_S: The Importance of K_S-K_L Interference

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    The BB-factories have measured CP asymmetries in the τπKSν\tau\to\pi K_S\nu and DKSπD\to K_S\pi modes. The KSK_S state is identified by its decay to two pions at a time that is close to the KSK_S lifetime. Within the Standard Model and many of its extensions, the asymmetries in these modes come from CP violation in K0Kˉ0K^0-\bar{K}^0 mixing. We emphasize that the interference between the amplitudes of intermediate KSK_S and KLK_L is as important as the pure KSK_S amplitude. Consequently, the measured asymmetries depend on the times over which the relevant decay rates are integrated and on features of the experiment.Comment: 4 pages, 4 figure

    Highlights from Five Years at the B Factories

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    The highlights and conflicts at the B Factories are briefly reviewed. CPCP violation was established in 2001 in B0J/ψKSB^0 \to J/\psi K_S and related modes, which has now become a precision measurement of CP violation in B0B^0-Bˉ0\bar B^0 mixing. However, the situation for the B0π+πB^0 \to \pi^+\pi^- and charmless bsb\to s modes, which probe also CP violation in the {\it decay} amplitude, are not quite settled yet. They could be hinting at presence of both strong (CP conserving) and new physics (CP violating) phases. We critically assess the developments and discuss some related discrepancies and highlights, such as observation of direct CP violation, and make a projection towards the next few years.Comment: 16 pages, 5 figures, to appear as Brief Review in Mod. Phys. Lett.

    Possibility of extracting the weak phase γ\gamma from ΛbΛD0\Lambda_b \to \Lambda D^0 decays

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    We explore the possibility of extracting the weak phase γ\gamma from pure tree decays ΛbΛ(D0,D0ˉ,DCP0)\Lambda_b \to \Lambda (D^0, \bar{D^0}, D^0_{CP}) in a model independent way. The CP violating weak phase γ\gamma can be determined cleanly, without any hadronic uncertainties, as these decay modes are free from the penguin pollutions. Furthermore, neither tagging nor time dependent studies are required to extract the angle γ\gamma with these modes.Comment: 12 pages, LaTex, Minor changes in the text, version to appear in Phys. Rev.

    The Adsorption and Collapse Transitions in a Linear Polymer Chain near an Attractive Wall

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    We deduce the qualitative phase diagram of a long flexible neutral polymer chain immersed in a poor solvent near an attracting surface using phenomenological arguments. The actual positions of the phase boundaries are estimated numerically from series expansion up to 19 sites of a self-attracting self avoiding walk in three dimensions. In two dimensions, we calculate analytically phase boundaries in some cases for a partially directed model. Both the numerical as well as analytical results corroborate the proposed qualitative phase diagram.Comment: 8 pages, 8 figures, revte

    Measurements of the Branching Fractions of the Semileptonic Decays Ξc0 → Ξ-ℓ+νℓ and the Asymmetry Parameter of Ξc0 → Ξ-π+

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    Using data samples of 89.5 and 711 fb-1 recorded at energies of s=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e+e- collider, we report measurements of branching fractions of semileptonic decays Ξc0→Ξ-ℓ+νℓ (ℓ=e or μ) and the CP-asymmetry parameter of Ξc0→Ξ-π+ decay. The branching fractions are measured to be B(Ξc0→Ξ-e+νe)=(1.31±0.04±0.07±0.38)% and B(Ξc0→Ξ-μ+νμ)=(1.27±0.06±0.10±0.37)%, and the decay parameter αΞπ is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξc0→Ξ-e+νe)/B(Ξc0→Ξ-μ+νμ) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter ACP=(αΞ-π++αΞ¯+π-)/(αΞ-π+-αΞ¯+π-)=0.024±0.052±0.014 is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the Ξc0→Ξ-π+ branching fraction. © 2021 authors. Published by the American Physical Society

    First test of lepton flavor universality in the charmed baryon decays ωc0 → ω-ℓ+νℓ using data of the Belle experiment

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    We present the first observation of the ωc0→ω-μ+νμ decay and present measurements of the branching fraction ratios of the ωc0→ω-ℓ+νℓ decays compared to the reference mode ωc0→ω-π+, (ℓ=e or μ). This analysis is based on 89.5 fb-1, 711 fb-1, and 121.1 fb-1 data samples collected with the Belle detector at the KEKB asymmetric-energy e+e- collider at the center-of-mass energies of 10.52 GeV, 10.58 GeV, and 10.86 GeV, respectively. The ωc0 signal yields are extracted by fitting Mωℓ and Mωπ spectra. The branching fraction ratios B(ωc0→ω-e+νe)/B(ωc0→ω-π+) and B(ωc0→ω-μ+νμ)/B(ωc0→ω-π+) are measured to be 1.98±0.13(stat)±0.08(syst) and 1.94±0.18(stat)±0.10(syst), respectively. The ratio of B(ωc0→ω-e+νe)/B(ωc0→ω-μ+νμ) is measured to be 1.02±0.10(stat)±0.02(syst), which is consistent with the expectation of lepton flavor universality. © 2022 authors. Published by the American Physical Society
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