119385684
GLUEBALL SPECTRUM FROM THE B.S. EQUATION
Abstract The mass of the glueballs is calculated in the B.S. equation framework. Under instantaneous approximation, the wave function of B.S. equations are obtained. The kernel is chosen as the sum of an one-gluon exchange potential, a contact interaction and a linear confining potential. The numerical results are in agreement with that of recent lattice calculation.
16008283
A New Approach to Construct the Operator on Lattice for the Calculation of Glueball Masses
We develop a new approach to construct the operator on lattice for the calculation of glueball mass, which is based on the connection between the continuum limit of the chosen operator and the quantum number $J^{PC}$ of the state studied. The spin of the state studied is then determined uniquely and directly in numerical simulation. Furthermore, the approach can be applied to calculate the mass of glueball states (ground or excited states) with any spin $J$ including $J\geq 4$. Under the quenched approximation, we present pre-calculation results for the masses of $0^{++}$ state and $2^{++}$ state, which are $1754(85)(86)MeV$ and $2417(56)(117)MeV$, respectively.
15138971
The first calculation for the mass of the ground 4(++) glueball state on lattice
Under the quenched approximation, we perform a lattice calculation for the mass of the ground 4(++) glueball state in E++ channel on a D = 3+1 lattice. Our calculation shows that the mass of this state is M-G(4(++)) = 3.65(6)(18) GeV, which rules out the 4(++) or mainly 4(++) glueball state interpretation for xi(2230).
122217753
THE BOUND STATE EQUATION FOR TWO GLUONS AND ITS SOLUTION
We derive the bound state equation for two gluons in relativistic quantum field theory, i.e. the Bethe–Salpeter (BS) equation for two gluons. To solve it, we choose the kernel as the sum of a one-gluon exchange potential, a contact interaction and a linear confining potential. Under instantaneous approximation, this BS equation is solved numerically. The spectrum and the BS wave function of the glueballs are obtained in this framework. The numerical results are in agreement with that of recent lattice calculation.
124930294
A Rigorous Calculation for the Radiator in e~+ e~-Process
Using the precise expression of electron, positron distribution function we obtained earlier, we derive the rigorous analytical expression of radiator in e~+e~- collision process. This series expression converges rapidly to the precise result required. The comparison with existing approximate expression is also given. Our result benefits the precice calculation for the radiative corrections in e~+e~- collision processess.
126028323
THE PRODUCTION PROCESS OF △ (1236) BY HIGH ENERGY NEUTRINOS, ACCORDING TO THE STRATON MODEL
117894041
Supersymmetric AdS3 × S2 M-theory geometries with fluxes
Motivated by a recent observation that the LLM geometries admit 1/4-BPS M5-brane probes with worldvolume AdS3 × Σ2 × S1 preserving the R-symmetry, SU(2) × U(1), we initiate a classification of the most general AdS3×S2 geometries in M-theory dual to two-dimensional chiral $$ \mathcal{N} = \left( {4,0} \right) $$ SCFTs. We retain all field strengths consistent with symmetry and derive the torsion conditions for the internal six-manifold, M6, in terms of two linearly independent spinors. Surprisingly, we identify three Killing directions for M6, but only two of these generate isometries of the overall ansatz. We show that the existence of this third direction depends on the norm of the spinors. With the torsion conditions derived, we establish the MSW solution as the only solution in the class where M6 is an SU(3)-structure manifold. Then, specialising to the case where the spinors define an SU(2)-structure, we note that supersymmetry dictates that all magnetic fluxes necessarily thread the S2. Finally, by assuming that the two remaining Killing directions are parallel and aligned with one of the two vectors defining the SU(2)-structure, we derive a general relationship for the two spinors before extracting a known class of solutions from the torsion conditions.
118749540
Holographic fermionic liquid with lattices
A bstractWe investigate the holographic fermions over a gravitational lattice background with a rather low temperature. Since the rotation symmetry is broken on the plane, the lattice effects change the shape of the Fermi surface within the first Brillouin zone from a circle to an ellipse. When the Fermi surface intersects with the Brillouin zone boundary, the band structure with a band gap is observed through a numerical analysis. We construct a lattice model sourced by a scalar field as well as an ionic lattice model without the scalar field. In both cases we find the similar physical results.
16931057
A Statistical Analysis of Point-like Sources in the Chandra Galactic Center Survey ∗
The Chandra Galactic Center Survey detected similar to 800 X-ray point-like sources in the 2 degrees x 0.8 degrees sky region around the Galactic Center. We study the spatial and luminosity distributions of these sources according to their spectral properties. Fourteen bright sources detected are used to fit jointly an absorbed power-law model, from which the power-law photon index is determined to be similar to 2.5. Assuming that all other sources have the same power-law form, the relation between hardness ratio and HI column density N-H is used to estimate the NH values for all sources. Monte Carlo simulations show that these sources are more likely concentrated in the Galactic center region, rather than distributed throughout the Galactic disk. We also find that the luminosities of the sources are positively correlated with their HI column densities, i.e., a more luminous source has a higher HI column density. From this relation, we suggest that the X-ray luminosity comes from the interaction between an isolated old neutron star and interstellar medium (mainly dense molecular clouds). Using the standard Bondi accretion theory and the statistical information of molecular clouds in the Galactic center, we confirm this positive correlation and calculate the luminosity range in this scenario, which is consistent with the observation (10(32)-10(35) erg s(-1)).
119284944
Thermal fluctuations in viscous cosmology
In this Letter we investigate the power spectrum of thermal fluctuations in very early stage of viscous cosmology. When the state parameter as well as the viscous coefficient of a barotropic fluid is properly chosen, a scale invariant spectrum with large non-Gaussianity can be obtained. In contrast to the results previously obtained in string gas cosmology and holographic cosmology, we find the non-Gaussianity in this context can be k-independent such that it is not suppressed at large scale, which is expected to be testified in future observation.
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.