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    The Heliocentric Distance Where the Deflections and Rotations of Solar Coronal Mass Ejections Occur

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    Understanding the trajectory of a coronal mass ejection (CME), including any deflection from a radial path, and the orientation of its magnetic field is essential for space weather predictions. Kay et al. (2015b) developed a model, Forecasting a CME's Altered Trajectory (ForeCAT), of CME deflections and rotation due to magnetic forces, not including the effects of reconnection. ForeCAT is able to reproduce the deflection of observed CMEs (Kay et al. 2015a). The deflecting CMEs tend to show a rapid increase of their angular momentum close to the Sun, followed by little to no increase at farther distances. Here we quantify the distance at which the CME deflection is "determined," which we define as the distance after which the background solar wind has negligible influence on the total deflection. We consider a wide range in CME masses and radial speeds and determine that the deflection and rotation of these CMEs can be well-described by assuming they propagate with constant angular momentum beyond 10 Rs. The assumption of constant angular momentum beyond 10 Rs yields underestimates of the total deflection at 1 AU of only 1% to 5% and underestimates of the rotation of 10%. Since the deflection from magnetic forces is determined by 10 Rs, non-magnetic forces must be responsible for any observed interplanetary deflections or rotations where the CME has increasing angular momentum.Comment: accepted in ApJ Letter

    State Transfer and Spin Measurement

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    We present a Hamiltonian that can be used for amplifying the signal from a quantum state, enabling the measurement of a macroscopic observable to determine the state of a single spin. We prove a general mapping between this Hamiltonian and an exchange Hamiltonian for arbitrary coupling strengths and local magnetic fields. This facilitates the use of existing schemes for perfect state transfer to give perfect amplification. We further prove a link between the evolution of this fixed Hamiltonian and classical Cellular Automata, thereby unifying previous approaches to this amplification task. Finally, we show how to use the new Hamiltonian for perfect state transfer in the, to date, unique scenario where total spin is not conserved during the evolution, and demonstrate that this yields a significantly different response in the presence of decoherence.Comment: 4 pages, 2 figure

    Forecasting a Coronal Mass Ejection's Altered Trajectory: ForeCAT

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    To predict whether a coronal mass ejection (CME) will impact Earth, the effects of the background on the CME's trajectory must be taken into account. We develop a model, ForeCAT (Forecasting a CME's Altered Trajectory), of CME deflection due to magnetic forces. ForeCAT includes CME expansion, a three-part propagation model, and the effects of drag on the CME's deflection. Given the background solar wind conditions, the launch site of the CME, and the properties of the CME (mass, final propagation speed, initial radius, and initial magnetic strength), ForeCAT predicts the deflection of the CME. Two different magnetic backgrounds are considered: a scaled background based on type II radio burst profiles and a Potential Field Source Surface (PFSS) background. For a scaled background where the CME is launched from an active region located between a CH and streamer region the strong magnetic gradients cause a deflection of 8.1 degrees in latitude and 26.4 degrees in longitude for a 1e15 g CME propagating out to 1 AU. Using the PFSS background, which captures the variation of the streamer belt position with height, leads to a deflection of 1.6 degrees in latitude and 4.1 degrees in longitude for the control case. Varying the CME's input parameters within observed ranges leads to the majority of CMEs reaching the streamer belt within the first few solar radii. For these specific backgrounds, the streamer belt acts like a potential well that forces the CME into an equilibrium angular position.Comment: 57 pages, 12 figures, accepted for publication in ApJ, fixed the overflow of text in Fig. 3 captio

    INCOME TAX EFFECTS ON BEEF COW REPLACEMENT STRATEGY

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    Livestock Production/Industries,

    Self-energy flows in the two-dimensional repulsive Hubbard model

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    We study the two-dimensional repulsive Hubbard model by functional RG methods, using our recently proposed channel decomposition of the interaction vertex. The main technical advance of this work is that we calculate the full Matsubara frequency dependence of the self-energy and the interaction vertex in the whole frequency range without simplifying assumptions on its functional form, and that the effects of the self-energy are fully taken into account in the equations for the flow of the two-body vertex function. At Van Hove filling, we find that the Fermi surface deformations remain small at fixed particle density and have a minor impact on the structure of the interaction vertex. The frequency dependence of the self-energy, however, turns out to be important, especially at a transition from ferromagnetism to d-wave superconductivity. We determine non-Fermi-liquid exponents at this transition point.Comment: 48 pages, 18 figure
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