Heavy flavours at colliders

Abstract

Abstract. I review some topics in the production and decays of heavy flavours that are relevant for collider physics. In particular, I discuss the present status and some recent progress related to masses, parton densities and fragmentation functions of heavy quarks, as well as threshold resummation, polarized onium production at high transverse momentum, and a factorization theorem for B → ππ decays.

Results in next-to-leading-log prompt-photon hadroproduction

“…Different values of E beam , therefore, probe different ranges of x T , as indicated by the upper labels on the plots. Note the significant reduction in scale dependence in both cases: with and without the inclusion of the constant term C (1) ab→γ . We also explored the renormalization-and factorization-scale dependence of our calculations.…”

“…b 0 being the first coefficient of the QCD β-function. The function ln N g (1) ab resums all the leading logarithmic (LL) contributions α n s ln n+1 N in the exponent, g…”

“…ab contains the next-to-leading logarithmic (NLL) terms α n s ln n N, and so forth. The analytic expressions for the functions g (1) ab , g (2) ab and C (1) ab→γ have been computed in Ref. [2].…”

“…In this talk, we consider the effect of soft-gluon resummation in prompt-photon production [1,2] near the "threshold" limit, that is to say for high transverse momentum. A more extensive treatment of this subject can be found in Ref.…”

Workshop summary and outlook

“…The agreement between measurements and expectations is improved if the scheme used to treat heavy flavor evolution is changed from the optimized RT VFN scheme [6] to that of ACOT [7] or to the FFN scheme [8].…”