Search results for "complexity"
showing 10 items of 1094 documents
Search forD0−D¯0Mixing and a Measurement of the Doubly Cabibbo-Suppressed Decay Rate inD0→KπDecays
2003
The authors present a search for D{sup 0}-{bar D}{sup 0} mixing using regions of phase space in which the rate of doubly Cabibbo-suppressed decays D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} relative to Cabibbo-favored decays D{sup 0} {yields} K{sup -} {pi}{sup +}{pi}{sup 0} is reduced. They analyze 230.4 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. They present results with and without the assumption of CP conservation. Assuming CP conservation, they measure the time-integrated mixing rate R{sub M} = (0.023{sub -0.014}{sup +0.018}(stat.) {+-} 0.004(syst.))%, and R{sub M} < 0.054% at the 95% confidence level. They find that the d…
Lattice QCD calculation of the electroweak box diagrams for the kaon semileptonic decays
2021
We present a lattice QCD calculation of the axial $\gamma W$-box diagrams relevant for the kaon semileptonic decays. We utilize a recently proposed method, which connects the electroweak radiative corrections in Sirlin's representation to that in chiral perturbation theory. It allows us to use the axial $\gamma W$-box correction in the SU(3) limit to obtain the low energy constants for chiral perturbation theory. From first principles our results confirm the previously used low energy constants provided by the minimal resonance model with a significant reduction in uncertainties.
Measurement of the Semileptonic Charge Asymmetry usingBs0→DsμXDecays
2013
We present a measurement of the time-integrated flavor-specific semileptonic charge asymmetry in the decays of B{sub s}{sup 0} mesons that have undergone flavor mixing, a{sub sl}{sup s}, using B{sub s}{sup 0} ({bar B}{sub s}{sup 0}) {yields} D{sub s}{sup {-+}} {mu}{sup {+-}} X decays, with D{sub s}{sup {-+}} {yields} {phi}{pi}{sup {-+}} and {phi} {yields} K{sup +}K{sup -}, using 10.4 fb{sup -1} of proton-antiproton collisions collected by the D0 detector during Run II at the Fermilab Tevatron Collider. A fit to the difference between the time-integrated D{sub s}{sup -} and D{sub s}{sup +} mass distributions of the B{sub s}{sup 0} and {bar B}{sub s}{sup 0} candidates yields the flavor-specif…
No-Forcing and No-Matching Theorems for Classical Probability Applied to Quantum Mechanics
2013
Correlations of spins in a system of entangled particles are inconsistent with Kolmogorov's probability theory (KPT), provided the system is assumed to be non-contextual. In the Alice-Bob EPR paradigm, non-contextuality means that the identity of Alice's spin (i.e., the probability space on which it is defined as a random variable) is determined only by the axis \alphai chosen by Alice, irrespective of Bob's axis \betaj (and vice versa). Here, we study contextual KPT models, with two properties: (1) Alice's and Bob's spins are identified as Aij and Bij, even though their distributions are determined by, respectively, \alphai alone and \betaj alone, in accordance with the no-signaling requir…
Low-energy constants from resonance chiral theory
2008
I discuss the recent attempts to build an effective chiral Lagrangian incorporating massive resonance states. A useful approximation scheme to organize the resonance Lagrangian is provided by the large-Nc limit of QCD. Integrating out the resonance fields, one recovers the usual chiral perturbation theory Lagrangian with explicit values for the low-energy constants, parameterized in terms of resonance masses and couplings. The resonance chiral theory generates Green functions that interpolate between QCD and chiral perturbation theory. Analyzing these Green functions, both for large and small momenta, one gets QCD constraints on the resonance couplings and, therefore, information on the low…
Study of the $^{15}$O(2p, γ )$^{17}$Ne cross section by Coulomb dissociation of $^{17}$Ne for the rp process of nucleosynthesis
2014
Acta physica Polonica / B 45(2), 229 - 234 (2014). doi:10.5506/APhysPolB.45.229
Radiative corrections in Dalitz decays of π0, η and η′ mesons
2019
We briefly summarize current experimental and theoretical results on the two important processes of the low-energy hadron physics involving neutral pions: the Dalitz decay of π0 and the rare decay π0 → e+e−. As novel results we present the complete set of radiative corrections to the Dalitz decays η(′) → l+l−γ beyond the soft-photon approximation, i.e. over the whole range of the Dalitz plot and with no restrictions on the energy of a radiative photon. The corrections inevitably depend on the η(′) → γ*γ(*) transition form factors.
Reduction of the uncertainty in the measurements of magnetic fields
2014
The paper deals with magnetic field measurement, carried out by using a broadband and isotropic instrument. These measurements are characterized by a very high uncertainty values if compared with the ones usually related to other electrical measurements. For these reasons, if the measurements are performed to assess the exposure of human beings, these large uncertainty values imply a high risk of wrong decision when there is the need to establish if a site complies or does not comply with a specified emission limits. A reduction of the uncertainty values implies a reduction of the risk. With this aim, we propose an approach which, in particular but very typical cases, allows an effective re…
Improved measurement of the CKM angleγinB∓→D(*)K(*)∓decays with a Dalitz plot analysis ofDdecays toKS0π+π−andKS0K+K−
2008
We report on an improved measurement of the Cabibbo-Kobayashi-Maskawa CP-violating phase {gamma} through a Dalitz plot analysis of neutral D meson decays to K{sub s}{sup 0}{pi}{sup +}{pi}{sup -} and K{sub s}{sup 0}K{sup +}K{sup -} produced in the processes B{sup {-+}} {yields} DK{sup {-+}}, B{sup {-+}} {yields} D* K{sup {-+}} with D* {yields} D{pi}{sup 0}, D{gamma}, and B{sup {-+}} {yields} DK*{sup {-+}} with K8{sup {-+}} {yields} K{sub S}{sup 0}{pi}{sup {-+}}. Using a sample of 383 million B{bar B} pairs collected by the BABAR detector, we measure {gamma} = (76 {+-} 22 {+-} 5{+-} 5){sup o} (mod 180{sup o}), where the first error is statistical, the second is the experimental systematic unc…
Quantum Computing: A Way to Break Complexity?
2003
The perception of time is given by the happening of some events that determines a variation in the state of the observed system. In this sense a computation, i.e. a set of well defined transformations that, starting from an initial state (the input) brings to a final state (the output), can be considered a time generator. Each ticking of the clock corresponds to the computer changes of its states. The speed of computation leads to a different perception of time as well as traveling by airplanes changed the perception of spatial distances.