Abstract:
The asymptotic freedom is known to split the leading-log BFKL pomeron into a series of isolated poles in the complex angular momentum plane. One of our earlier findings was that the subleading hard BFKL exchanges decouple from such experimentally important observables as small-x charm Fc2, beauty Fb2 and the longitudinal structure functions of the proton at moderately large Q2. For instance, we predicted precocious BFKL asymptotics of Fc2(x,Q2) with intercept of the rightmost BFKL pole αIP(0)−1=ΔIP≈0.4. On the other hand, the small-x open beauty photo- and electro-production probes the vacuum exchange for much smaller color dipoles which entails significant subleading vacuum pole corrections to the small-x behavior. In view of the accumulation of the experimental data on small-xFc2 and Fb2 we extend our 1999 predictions to the kinematical domain covered by new HERA measurements. Our parameter-free results agree well with the determination of Fc2, FL and published H1 results on Fb2 but slightly overshoot the very recent (2008, preliminary) H1 results on Fb2.
Citation:
R. Fiore, N. N. Nikolaev, V. R. Zoller, “The BFKL-Regge factorization and Fb2, Fc2, FL at HERA: physics implications of nodal properties of the BFKL eigenfunctions”, Pis'ma v Zh. Èksper. Teoret. Fiz., 90:5 (2009), 361–367; JETP Letters, 90:5 (2009), 319–325