M. Carena et al., ANALYTICAL EXPRESSIONS FOR RADIATIVELY CORRECTED HIGGS MASSES AND COUPLINGS IN THE MSSM, Physics letters. Section B, 355(1-2), 1995, pp. 209-221
We propose, for the computation of the Higgs mass spectrum and couplin
gs, a renormalization-group improved leading-log approximation, where
the renormalization scale is fixed to the top-quark pole mass. For the
case m(A) similar to M(SUSY), our leading-log approximation differs b
y less than 2 GeV from previous results on the Higgs mass computed usi
ng a nearly scale independent renormalization-group improved effective
potential up to next-to-leading order. Moreover, for the general case
m(A) less than or similar to M(SUSY), we provide analytical formulae
(including two-loop leading-log corrections) for all the masses and co
uplings in the Higgs sector. For M(SUSY) less than or similar to 1.5 T
eV and arbitrary values of m(A), tan beta and the stop mixing paramete
rs, they reproduce the numerical renormalization-group improved leadin
g-log result for the Higgs masses with an error of less than 3 GeV. Fo
r the Higgs couplings, our analytical formulae reproduce the numerical
results equally well. Comparison with other methods is also performed
.