Search for the Higgs boson: theoretical perspectives

We present a short review of experimental and theoretical constraints on the mass of the Standard Model Higgs boson. We briefly illustrate the unsatisfactory aspects of the standard theory, and we present some general considerations about possible non-standard scenarios.Comment: 13 pages latex, 6 PS figures. Talk given at Les Rencontres de la Vallee d'Aoste, La Thuile, Italy, March 4-10, 200

Heavy quark production: recent developments

I discuss some aspects of the comparison between QCD predictions and experimental data in charm and bottom production.Comment: 5 pages Latex, uses epsfig.sty,aipproc.sty, 7 eps figures included. Talk given at the 5th International Workshop on Deep Inelastic Scattering and QCD (DIS 97), Chicago, IL, 14-18 Apr 199

Heavy Flavour Production

We review the status of heavy flavour production in QCD. Comparison of experimental and theoretical results for top and bottom production are given. Selected topics in charm production are also discussed.Comment: 18 pages, Latex, epsfig, 12 tar-gzip-uuencoded figures. Invited talk given at the XV International conference "Physics in Collisions", Cracow, Poland, June 8-10, 199

Indication for Light Sneutrinos and Gauginos from Precision Electroweak Data

The present Standard Model fit of precision data has a low confidence level, and is characterized by a few inconsistencies. We look for supersymmetric effects that could improve the agreement among the electroweak precision measurements and with the direct lower bound on the Higgs mass. We find that this is the case particularly if the 3.6 sigma discrepancy between sin^2 theta_eff from leptonic and hadronic asymmetries is finally settled more on the side of the leptonic ones. After the inclusion of all experimental constraints, our analysis selects light sneutrinos, with masses in the range 55-80 GeV, and charged sleptons with masses just above their experimental limit, possibly with additional effects from light gauginos. The phenomenological implications of this scenario are discussed.Comment: 17 pages LaTex, 9 figures, uses epsfi

Perturbative corrections to semileptonic b decay distributions

We compute O(alpha_s) and O(alpha_s^n beta_0^{n-1}) (BLM) corrections to the five structure functions relevant for b->q l nu decays and apply the results to the moments of a few distributions of phenomenological importance. We present compact analytic one-loop formulae for the structure functions, with proper subtraction of the soft divergence.Comment: 23 pages, LaTex. A number of textual changes are added for clarity, a missing definition is provide

The gluon contribution to the polarized structure function g2g_2

We compute the structure function $g_2$ for a gluon target in perturbative QCD at order \as. We show that its first moment vanishes, as predicted by the Burkhardt-Cottingham sum rule.Comment: 9 pages Latex, uses epsfig.sty, 1 eps figure include

Polarized parton distributions in perturbative QCD

We review the main results of next-to-leading order QCD analyses of polarized deep-inelastic scattering data, with special attention to the assessment of theoretical uncertainties.Comment: 4 pages Latex, 1 ps figure. Talk given at NUCLEON '99, Frascati(Italy), June 7-9 199