Parity-Violating Nuclear Force as derived from QCD Sum Rules

Parity-violating nuclear force, as may be accessed from parity violation studies in nuclear systems, represents an area of nonleptonic weak interactions which has been the subject of experimental investigations for several decades. In the simple meson-exchange picture, parity-violating nuclear force may be parameterized as arising from exchange of \pi, \rho, \omega, or other meson(s) with strong meson-nucleon coupling at one vertex and weak parity-violating meson-nucleon coupling at the other vertex. The QCD sum rule method allows for a fairly complicated, but nevertheless straightforward, leading-order loop-contribution determination of the various parity-violating MNN couplings starting from QCD (with the nontrivial vacuum) and Glashow-Salam-Weinberg electroweak theory. We continue our earlier investigation of parity-violating \pi NN coupling (by Henley, Hwang, and Kisslinger) to other parity-violating couplings. Our predictions are in reasonable overall agreement with the results estimated on phenomenological grounds, such as in the now classic paper of Desplanques, Donoghue, and Holstein (DDH), in the global experimental fit of Adelberger and Haxton (AH), or the effective field theory (EFT) thinking of Ramsey-Musolf and Page (RP).Comment: 17 pages, 5 figure

Heating of Flare Loops With Observationally Constrained Heating Functions

We analyze high cadence high resolution observations of a C3.2 flare obtained by AIA/SDO on August 1, 2010. The flare is a long duration event with soft X-ray and EUV radiation lasting for over four hours. Analysis suggests that magnetic reconnection and formation of new loops continue for more than two hours. Furthermore, the UV 1600\AA\ observations show that each of the individual pixels at the feet of flare loops is brightened instantaneously with a timescale of a few minutes, and decays over a much longer timescale of more than 30 minutes. We use these spatially resolved UV light curves during the rise phase to construct empirical heating functions for individual flare loops, and model heating of coronal plasmas in these loops. The total coronal radiation of these flare loops are compared with soft X-ray and EUV radiation fluxes measured by GOES and AIA. This study presents a method to observationally infer heating functions in numerous flare loops that are formed and heated sequentially by reconnection throughout the flare, and provides a very useful constraint to coronal heating models.Comment: This paper is revise

Quasi-adiabatic Continuation of Quantum States: The Stability of Topological Ground State Degeneracy and Emergent Gauge Invariance

We define for quantum many-body systems a quasi-adiabatic continuation of quantum states. The continuation is valid when the Hamiltonian has a gap, or else has a sufficiently small low-energy density of states, and thus is away from a quantum phase transition. This continuation takes local operators into local operators, while approximately preserving the ground state expectation values. We apply this continuation to the problem of gauge theories coupled to matter, and propose a new distinction, perimeter law versus "zero law" to identify confinement. We also apply the continuation to local bosonic models with emergent gauge theories. We show that local gauge invariance is topological and cannot be broken by any local perturbations in the bosonic models in either continuous or discrete gauge groups. We show that the ground state degeneracy in emergent discrete gauge theories is a robust property of the bosonic model, and we argue that the robustness of local gauge invariance in the continuous case protects the gapless gauge boson.Comment: 15 pages, 6 figure

Structure and stability of quasi-two-dimensional boson-fermion mixtures with vortex-antivortex superposed states

We investigate the equilibrium properties of a quasi-two-dimensional degenerate boson-fermion mixture (DBFM) with a bosonic vortex-antivortex superposed state (VAVSS) using a quantum-hydrodynamic model. We show that, depending on the choice of parameters, the DBFM with a VAVSS can exhibit rich phase structures. For repulsive boson-fermion (BF) interaction, the Bose-Einstein condensate (BEC) may constitute a petal-shaped "core" inside the honeycomb-like fermionic component, or a ring-shaped joint "shell" around the onion-like fermionic cloud, or multiple segregated "islands" embedded in the disc-shaped Fermi gas. For attractive BF interaction just below the threshold for collapse, an almost complete mixing between the bosonic and fermionic components is formed, where the fermionic component tends to mimic a bosonic VAVSS. The influence of an anharmonic trap on the density distributions of the DBFM with a bosonic VAVSS is discussed. In addition, a stability region for different cases of DBFM (without vortex, with a bosonic vortex, and with a bosonic VAVSS) with specific parameters is given.Comment: 8 pages,5 figure