Related papers: Doped Parton Distributions
The prediction of differential cross-sections in hadron-hadron scattering processes is typically performed in a scheme where the heavy-flavour quarks ($c, b, t$) are treated either as massless or massive partons. In this work, a method to…
We compare `fixed flavor number scheme' (FFNS) and `variable flavor number scheme' (VFNS) parton model predictions at high energy colliders. Based on our recent LO- and NLO-FFNS dynamical parton distributions, we generate radiatively two…
We present results of our studies of double-parton scattering (DPS) effects in simultaneous production of heavy flavour mesons (charm and bottom). We discuss production of charm-bottom and bottom-bottom meson-meson pairs in proton-proton…
The electron, positron, and photon Parton Distribution Functions (PDFs) of the unpolarised electron have recently been computed at the next-to-leading logarithmic accuracy in QED, by adopting the $\overline{\rm MS}$ factorisation scheme. We…
In this work we present a new approach to threshold resummation in processes with heavy quarks. In particular we will focus on the differential decay rate of a color-singlet particle into a $b \bar b$ pair and we will show how to resum in a…
We introduce a Hybrid Variable Flavor Number Scheme for heavy flavors, denoted H-VFNS, which incorporates the advantages of both the traditional Variable Flavor Number Scheme (VFNS) as well as the Fixed Flavor Number Scheme (FFNS). By…
In this work we explore first necessary steps to contruct a fully massive version of a variable flavour number scheme. In particular we focus, as an example, on an extension of the five-flavour scheme, where instead of neglecting explicit…
There are presently two approaches to calculating heavy quark production for the deeply inelastic scattering process in current literature. The conventional fixed-flavor scheme focuses on the flavor creation mechanism and includes the heavy…
I consider the effect on partons distribution functions (PDFs) of changes in the theoretical procedure used in a PDF fit. I consider using the 3-flavour fixed flavour number scheme instead of the standard general mass variable flavour…
We present a new prescription to account for heavy quark mass effects in the determination of parton distribution functions (PDFs) based on the FONLL scheme. Our prescription makes explicit use of the freedom to choose the number of active…
Precision measurements of heavy-flavor hadroproduction at the Large Hadron Collider (LHC) have the ability to probe heavy-flavor parton distribution functions (PDFs) in the proton. Sensitivity of inclusive $B^\pm$ meson production cross…
Beyond leading-order, perturbative QCD requires a choice of factorisation scheme to define the parton distribution functions (PDFs) and hard-process cross-section. The modified minimal-subtraction ($\overline{\mathrm{MS}}$) scheme has long…
We investigate the uncertainties of the heavy-quark parton distribution functions in the variable flavor number scheme. Because the charm- and bottom-quark parton distribution functions (PDFs) are constructed predominantly from the gluon…
We compute the total cross-section for Higgs boson production in bottom-quark fusion using the so-called FONLL method for the matching of a scheme in which the $b$-quark is treated as a massless parton to that in which it is treated as a…
We discuss production of $c \bar c$-pairs within $k_T$-factorization approach (off-shell initial partons) with unintegrated parton distribution functions (uPDFs). We present a consistent prescription which merges the standard leading-order…
The production of single top-quarks in the t-channel at hadron colliders imposes strong analytic constraints on parton distribution functions (PDFs) through its double deeply inelastic scattering (DDIS) form. We exploit this to provide…
In this work, the impact of recent measurements of heavy-flavour production in $pp$ collisions on parton distribution functions (PDFs) and their uncertainties is studied. In this regard, the absolute and normalised cross sections of beauty…
In order to successfully describe DIS data, one must take heavy quark mass effects into account. This is often achieved using so called variable flavour number schemes, in which a parton distribution for the heavy quark species is defined…
I review the various methods for taking account of finite quark masses in DIS and related processes. I pay particular attention to the so-called variable flavour number schemes (VFNS) which are designed to extrapolate smoothly from the…
We introduce a Hybrid Variable Flavor Number Scheme (H-VFNS) for heavy flavors, which incorporates the advantages of both the traditional Variable Flavor Number Scheme (VFNS) as well as the Fixed Flavor Number Scheme (FFNS). We include an…