35673041
Decays of excited charmed Lambda -type and Sigma -type baryons in heavy hadron chiral perturbation theory.
Ground states and some excited p-wave states of heavy baryons are studied within the framework of heavy hadron chiral perturbation theory. The effective Lagrangian is written out to terms of the next-to-leading order in 1/${\mathit{m}}_{\mathit{Q}}$ or 1/${\mathrm{\ensuremath{\Lambda}}}_{\mathrm{\ensuremath{\chi}}}$. The coupling constants are estimated using the experimental data of \ensuremath{\Lambda} and \ensuremath{\Sigma} baryons in the static limit of the s quark. The single pion and double pion decay rates of these charmed baryons have been estimated. The numerical results show that both ${\mathrm{\ensuremath{\Lambda}}}_{\mathit{c}}$(1/${2}^{\mathrm{\ensuremath{-}}}$) and ${\mathrm{\ensuremath{\Lambda}}}_{\mathit{c}}$(3/${2}^{\mathrm{\ensuremath{-}}}$) are very narrow. We conclude that the two pion channel may offer the best hope for detecting the ${\mathrm{\ensuremath{\Sigma}}}_{\mathit{c}}$(3/${2}^{\mathrm{\ensuremath{-}}}$) and ${\mathrm{\ensuremath{\Sigma}}}_{\mathit{c}}$(1/${2}^{\mathrm{\ensuremath{-}}}$) p-wave doublet.
123961702
diagonalization of anomalous dimension matrices of Higher Twist Operators and Conformal Covariance
Anomalous dimension matrices of operators based on the twist-3 operator (or )are calculated and diagonalized. We find that for these operators the diagonal operators are not conformal operators. The higher twist effects of the pionic asymptotic wave function and form factor are also investigated.
124195329
W-T IDENTITIES, NORMALIZATION OF THE BS WAVE-FUNCTION AND PROPERTIES OF THE PION
We discuss some problems concerned with the normalization of the BS wave function in connection with Ward-Takahashi identities in the Lorentz covariant Bethe-Salpeter formalism proposed in the previous work. Physical quantities of the pion as a Goldstone boson, including the π0 → 2γ amplitude are calculated in the QCD motivated models and results are in agreement with the experimental data.
42952650
Null vectors in super Virasoro representations of the superconformal algebra.
Using the fusion procedure, a complete and straightforward algorithm for finding null vectors in Verma modules of the {ital N}=1 superconformal algebra is given.
123741473
Hadronic Width of P-Wave Heavy Quarkonium States with Massive Gluons
The hadronic decay widths of P-wave quarkonium states are calculated in the broken QCD with massive gluons. The comparison with preliminary data is also discussed.
122507937
Superconformal models from super W-constrained SKP hierarchies via the super Kontsevich-Miwa transformation
39279547
Quantum field effect on symmetry breaking and restoration in anisotropic spacetimes.
A one-loop effective potential for {phi}{sup 4} theory on a Bianchi type-I universe is evaluated in the adiabatic approximation. It is used to see the quantum-field effects on symmetry breaking and restoration in anisotropic spacetimes. The results show that the fate of symmetry will not be changed in the cases of conformal coupling or a vanishing scale curvature, and only for some suitable values of scalar-gravitational coupling could the symmetry be radiatively broken or restored.
73519332
RHIC Performance for FY10 200 GeV Au+Au Heavy Ion Run
Since the last successful RHIC Au+Au run in 2007 (Run-7), the RHIC experiments have made numerous detector improvements and upgrades. In order to benefit from the enhanced detector capabilities and to increase the yield of rare events in the acquired heavy ion data a significant increase in luminosity is essential. In Run-7 RHIC achieved an average store luminosity of = 12 × 10 cm−2 s−1 by operating with 103 bunches (out of 111 possible), and by squeezing to β∗ = 0.85 m. This year, Run-10, we achieved = 20 × 10 cm−2 s−1, which put us an order of magnitude above the RHIC design luminosity. To reach these luminosity levels we decreased β∗ to 0.75 m, operated with 111 bunches per ring, and reduced longitudinal and transverse emittances by means of bunched-beam stochastic cooling. In addition we introduced a lattice to suppress intra-beam scattering (IBS) in both RHIC rings, upgraded the RF control system, and separated transition crossing times in the two rings. We present an overview of the changes and the results of Run-10 performance.
29696360
Nonperturbative effects on the Wilson coefficients and the Delta I=(1/2 rule in kaon decays.
We apply the vacuum-background-field method and the modified renormalization-group equation in the energy region {mu}{lt}1 GeV to correct the Wilson coefficients in the {Delta}{ital S}=1 effective weak Hamiltonian responsible for {ital K}{r arrow}2{pi} decays. We find that the change of {ital C}{sub {plus minus}} results in an enhancement to the {Delta}{ital I}={1/2} amplitude by a factor of 2 at the scale {mu}=0.6 GeV for {ital K}{r arrow}2{pi} decays.
12724895
Reexamination of the perturbative pion form factor with Sudakov suppression.
The perturbative pion form factor with Sudakov suppression is reexamined. To guarantee the reliability of the perturbative calculations we suggest that the running coupling constant should be frozen at {alpha}{sub {ital s}}({ital t}={l_angle}{ital k}{sub {ital T}}{r_angle}) and {l_angle}{ital k}{sub {ital T}}{r_angle} is the average transverse momentum which can be determined by the pionic wave function. In addition we correct the previous calculations about the Sudakov suppression factor which plays an important role in the perturbative calculations for the pion form factor.
29791617
Gravitational field of radiating cosmic string.
We examine the Einstein equation with the energy-momentum tensors which correspond to an infinite line string of finite radius plus an outgoing radiation field. It is used to see the effect of the radiation field on the spacetime of a cosmic string. We make some assumptions about the metric coefficients and find a class of exact solutions. The result can be applied to studying the back reaction on a radiating cosmic string.