Effective field theory approach to open heavy flavor production in heavy-ion collisions

Abstract

Abstract:We develop a version of Soft Collinear Effective Theory (SCET) which includes finite quark masses, as well as Glauber gluons that describe the interaction of collinear partons with QCD matter. In the framework of this new effective field theory, labeled SCET M,G , we derive the massive splitting functions in the vacuum and the QCD medium for the processes Q → Qg, Q → gQ and g → QQ. The numerical effects due to finite quark masses are sizable and our results are consistent with the traditional approach to parton energy loss in the soft gluon emission limit. In addition, we present a new framework for including the medium-induced full splitting functions consistent with next-to-leading order calculations in QCD for inclusive hadron production. Finally, we show numerical results for the suppression of D-and B-mesons in heavy ion collisions at √ s NN = 5.02 TeV and 2.76 TeV and compare to available data from the LHC.

An effective theory of quarkonia in QCD matter

“…[10]. The energy loss evaluation is carried out in the soft gluon emission limit of the full in-medium splitting kernels [11,12,13]. We find that the energy loss approach overpredicts the suppression of J/ψ in applicable p T > 10 GeV range by a factor of 2 to 3 in both minimum bias and central collisions.…”

Jet charge modification in finite QCD matter

“…It has been used quite extensively in Refs. [49,50,54,68] to describe hadron production and carry our resummation numerically in a strongly-interacting environment. In a QCD medium the evolution of the charge weighted fragmentation function becomes…”

“…[38,39]. In analogy to the vacuum case, the medium corrections to the jet function are constructed with the help of the medium-induced splitting functions [52][53][54][55][56] that capture the full collinear branching dynamics of energetic parton evolution in a QCD medium. A similar application of the medium-induce splitting functions can be found in Refs.…”

Working Group 5: Physics with Heavy Flavours

“…As a consequence of its large mass, it can decay weakly via an on-shell W boson on extremely short time scales before the effects of decoherence or hadronisation can occur. On the order of 10 7 tt pairs have been produced in pp collisions at the LHC so far. Both inclusive and differential measurements of tt production have reached a remarkable precision for all decay channels at centreof-mass energies of 7, 8, and 13 TeV, and these new data, coupled to steadfast advances in theory accuracy [1], have led to an improved understanding of proton structure (including the photon PDF contribution [2]) as well as stronger constraints on Standard Model parameters such α s and m t , as elaborated in Sec.…”

“…Recent theoretical progress in the modelling of these effects has been made in Ref. [7], where the interaction of heavy quarks with a nuclear medium has been modelled in the framework of soft collinear effective field theory (SCET). A comparison of these predictions for D hadrons with the corresponding CMS data is shown in Fig.…”