摘要:

The author suggests that non‐irreducible representations of the Lorentz group should be investigated. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.33110

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Some processes for which higher order corrections in the strong coupling constant have been calculated are reviewed.

ISSN:0094-243X    

DOI:10.1063/1.33111

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A Sterman‐Weinberg calculation is presented for e+e−annihilation. 9AIP)

ISSN:0094-243X    

DOI:10.1063/1.33112

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

A pure perturbative calculation of multijet events is described in terms of a variable C, which is a measure of ’multijetiness . The large contributions to the higher order corrections are discussed and a comparison of the theoretical result with some of the experimental data is made.

ISSN:0094-243X    

DOI:10.1063/1.33113

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We have calculated the 0(&agr;s) corrections to the gluonic width of &Ugr;‐like mesons in QCD. We obtain &Ggr;g=&Ggr;0g[1+(3.8±0.5) &agr;s(M&Ugr;)/&pgr;] in the M¯S¯ scheme renormalized at M&Ugr;. With this correction, the measured value of the leptonic branching ratio of the &Ugr; implies that &Lgr;M¯S¯=100 MeV, with experimental errors of+34−25MeV and comparable theoretical uncertainties. A similar analysis of the &psgr; and &psgr;′ data is consistent with this value of &Lgr;M¯S¯. We also present 0(&agr;s) corrections to other quantities in quarkonium decay.

ISSN:0094-243X    

DOI:10.1063/1.33114

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We calculate the first nonleading logarithm corrections to the longitudinal structure function of deep inelastic scattering, using the operator product expansion and the renormalization group. We use dimensional regularization to regulate both ultraviolet and infrared divergences.

ISSN:0094-243X    

DOI:10.1063/1.33115

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The effect of all possible parton subprocesses on the normalization of the Drell‐Yan cross section d&sgr;/dQ2is investigated. The relation with deep‐inelastic scattering is discussed, and we show how the results, and in particular the quark‐quark correction, can be converted to the MS‐scheme. The effect of all contributions on the proton‐proton cross section is calculated from deep‐inelastic scattering data, using second order QCD, with matching conventions. We consider the full order‐&agr;scorrections, the second order qq correction and make an estimate of the gluon‐gluon contribution.

ISSN:0094-243X    

DOI:10.1063/1.33097

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

Large momentum transfer exclusive processes and the short distance structure of hadronic wave functions can be systematically analyzed within the context of perturbative QCD. We review predictions of meson form factors, two‐photon processes &ggr;&ggr; → MM¯, hadronic decays of heavy quark systems, and a number of other related QCD phenomena.

ISSN:0094-243X    

DOI:10.1063/1.33098

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

The order &agr;2s(Q2) corrections to the pion form‐factor F&pgr;(Q2) are calculated using perturbative QCD and dimensional regularization. The result is compared in the MS and MOM subtraction schemes and plotted as a function of Q2/Qˆ2where Qˆ is the subtraction point. There is a large dependence on the scheme, the definition of the running coupling constant &agr;s(Qˆ2) and the subtraction point Qˆ. We find it best to invert the &bgr;‐function equation for the definition of &agr;srather than make an expansion in powers of log(Q2/&Lgr;2). We study two methods to optimize the result with respect to Qˆ: Stevenson’s prescription and putting the 0(&agr;2s) term to zero. Both methods give almost the same value for Q2F&pgr;and this value is scheme independent.

ISSN:0094-243X    

DOI:10.1063/1.33100

出版商:AIP    

年代:1981

数据来源: AIP

摘要:

We review recent developments in the study of hadronic jets produced in hard processes, based on perturbative QCD and, in particular, on jet calculus. The first part is a brief summary of what has been done in the leading log approximation, presented from a somewhat novel point of view. In the second part, we derive and discuss the parton‐probabilistic algorithms. The results and implications of the calculation to the next‐to‐leading order are discussed at the end.

ISSN:0094-243X    

DOI:10.1063/1.33101

出版商:AIP    

年代:1981

数据来源: AIP