Recent H1 data on triple differential dijet cross sections in e ± p interactions in the region of low photon virtualities are shown to be in reasonable agreement with the predictions of the NLO QCD calculations obtained using the program NLOJET++. The implications of this observation for the phenomenological relevance of the concept of resolved virtual photon are discussed.

We present analytic results for first order radiative QCD corrections to e+e− annihilation processes into quarks and gluons under the special aspect of polarized final state particles. This aspect involves single-spin polarization, gluon polarization, and the correlation between quark spins for massive final state quarks.

The Ω− magnetic moment was measured very accurately and experimentalists remarked that it differs from the theoretical estimates, thus posing a challenge to the latter. One such estimation uses QCDSR. We revisit this sumrule method, using condensate parameters which were obtained from fitting the differences (μp − μn), (μΣ+ − μΣ−) and (μΞ0 − μΞ−) [1] and confirm the experimental number. The μ∆+...

Measurements of many Standard Model constants are clouded by uncertainties in nonperturbative QCD parameters that relate measurable quantities to the underlying parton-level processes. Generally these QCD parameters have been obtained from model calculations with large uncertainties that are difficult to quantify. The CLEO Collaboration has taken a major step towards reducing these uncertaintie...

I review the NLO QCD calculations of the branching ratio for B → Xsγ in the SM. Including the leading electromagnetic corrections, one obtaines BR(B → Xsγ) = (3.32±0.30)×10−4. Confronting theory with the newest data, an updated value for |Vts| is obtained: |Vts| = 0.037±0.007. Theoretical progress on the photon energy spectrum is also discussed. The inclusive FCNC semileptonic decays in the SM ...

To apply lattice QCD in the calculation of glueball spectrum it is needed firstly to know associated operators acting on vacuum. We show how to find all the independent representations and operators, of group SO(3) at different dimension, since the work is not trivial. Then, we decompose these representation into irreducible representation of O group, which are listed in the note. At last we ar...

We study the properties of the 0 glueball at finite temperature using SU(3) quenched lattice QCD. We find a significant thermal effects near Tc. We perform the χ fit analyses adopting two Ansätze for the spectral function, i.e., the conventional narrow-peak Ansatz and an advanced Breit-Wigner Ansatz. The latter is an extension of the former, taking account of the appearance of the thermal width...

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I review recent developements in lattice QCD at finite temperature, including the determination of the transition temperature Tc, equation of state and diffenet static screening lengths. The lattice data suggest that at temperatures above 1.5Tc the quark gluon plasma can be considered as gas consisting of quarks and gluons.