15649438
Generalized inverse-Cowling approximation for polar w-mode oscillations of neutron stars
Adopting the Lindblom-Detweiler formalism for polar oscillations of neutron stars, we study the w-mode oscillation and find that the Lagrangian change in pressure, measured by the physical quantity X, is negligibly small. Based on this observation, we develop the generalized inverse-Cowling approximation (GICA) with the approximation X = X' = 0, where X' is the derivative of X with respect to the circumferential radius for w-mode oscillations of neutron stars. Under the GICA, w-mode oscillations are described by a second-order differential system, which can yield accurate frequencies and damping rates of quasi-normal modes.
119349480
Determination of the internal structure of neutron stars from gravitational wave spectra
In this paper the internal structure of a neutron star is shown to be inferrable from its gravitational-wave spectrum. Iteratively applying the inverse scheme of the scaled coordinate logarithmic perturbation method for neutron stars proposed by Tsui and Leung [Astrophys. J. {\bf 631}, 495 (2005)], we are able to determine the mass, the radius and the mass distribution of a star from its quasi-normal mode frequencies of stellar pulsation. In addition, accurate equation of state of nuclear matter can be obtained from such inversion scheme. Explicit formulas for the case of axial $w$-mode oscillation are derived here and numerical results for neutron stars characterized by different equations of state are shown.
121764215
Note on integrability of marginally deformed ABJ(M) theories
A bstractWe study the anomalous dimensions of operators in the scalar sector of β-deformed ABJ(M) theories. We show that the anomalous dimension matrix at two-loop order gives an integrable Hamiltonian acting on an alternating SU(4) spin chain with the spins at odd lattice sides in the fundamental representation and the spins at even lattices in the anti-fundamental representation. We get a set of β-deformed Bethe ansatz equations which give the eigenvalues of Hamiltonian of this deformed spin chain system. Based on our computations, we also extend our study to non-supersymmetric three-parameter γ-deformation of ABJ(M) theories and find that the corresponding Hamiltonian is the same as the one in β-deformed case at two-loop level in the scalar sector.
104086427
N* production from p p and anti-p p collisions
With an effective Lagrangian approach, we give a full analysis on the NN→NNππ and pp→pnπ+ reactions for proton beam energy from 1 to 1.5 GeV. The results are very consistent with the experiment data from CELSIUS, KEK, COSY, and so on. Based on these results, we consider the NN→NNππ and pp→pnπ+ for proton beam energy up to 4 GeV. Compare to the pp collisions, there are many benefits to study N* resonances in these two reactions. And for the high proton beam energy up to 15 GeV, we consider some new resonances with hidden charm which are definitely beyond three constituent quarks model in the pp→ppJ/ψ and pp→ppηc, where there are very nice places to find these new Ncc*. The predicted results about pp collisions can be looked for at the forthcoming PANDA/FAIR experiments.
117757882
A new regularization of loop integral, no divergence, no hierarchy problem
We find a new regularization scheme which is motivated by the Bose-Einstein condensation. The energy of the virtual particle is considered as discrete. Summing them and regulating the summation by the Riemann $\zeta$ function can give the result of loop integral. All the divergences vanish, we can get almost the same results as Dimensional Regularization. The prediction beyond Dimensional Regularization is also shown in the QED. The hierarchy problem of the radiative correction of scalar mass completely vanish.
118473731
Some properties of the holographic fermions in an extremal charged dilatonic black hole
We study the properties of the Green's functions of the fermions in the extremal charged dilatonic black hole proposed by Gubser and Rocha [Phys. Rev. D \textbf{81}, 046001 (2010)]. We find that many properties seem to be in agreement with that of Fermi liquid. Especially, the dispersion relation is linear. It is very different from that found in the extremal Reissner-Nordstr$\ddot{o}$m (RN) black hole for massless fermion, which is obviously non-Fermi liquid due to a nonlinear dispersion relation. However, for another scaling behavior of the height of $ImG_{11}$ at the maximum, the scaling exponent is not one, which is at odds with that found in the RN black hole.
55060589
Finite-volume Hamiltonian method for coupled-channels interactions in lattice QCD
Within a multi-channel formulation of $\pi\pi$ scattering, we investigate the use of the finite-volume Hamiltonian approach to resolve scattering observables from lattice QCD spectra. The asymptotic matching of the well-known L\"uscher formalism encodes a unique finite-volume spectrum. Nevertheless, in many practical situations, such as coupled-channel systems, it is advantageous to interpolate isolated lattice spectra in order to extract physical scattering parameters. Here we study the use of the Hamiltonian framework as a parameterisation that can be fit directly to lattice spectra. We find that with a modest amount of lattice data, the scattering parameters can be reproduced rather well, with only a minor degree of model dependence.