The virtual photon structure function g 1 (x,Q , P ), which can be obtained in polarized ee colliding-beam experiments, is investigated for Λ ≪ P 2 ≪ Q, where −Q (−P ) is the mass squared of the probe (target) photon. The analysis is made to next-to-leading order in QCD, in the framework of the QCD improved parton model with the DGLAP evolution equations. The non-leading corrections significant...

We examine the radiative corrections to the mass of the lightest Higgs boson in the minimal supersymmetric extension of the standard model. We use the renormalization-group improved effective potential which includes the next-to-leading-order contributions. We find that, contrary to the result of Espinosa and Quirós, the higher-order corrections to the lightest Higgs boson mass are non-negligib...

We investigate the transition of the polarized photon structure function g 1 (x,Q , P ) when the target photon shifts from on-shell (P 2 = 0) to far off-shell (P 2 ≫ Λ) region. The analysis is performed to the nextto-leading order in QCD. The first moment of g 1 which vanishes for the real photon, turns to be a negative value when target photon becomes off-shell. The explicit P -dependence of t...

We investigate the positivity constraints for the structure functions of both virtual and real photon. From the Cauchy-Schwarz inequality we derive three positivity conditions for the general virtual photon case, which reduce, in the real photon case, to one condition relating the polarized and unpolarized structure functions. YNU-HEPTh-01-102 CPT-2001/P.4242 KUCP-195 October 2001 e-mail addres...