6 research outputs found
The impact of the LHCb production cross-section on parton distribution functions and determining the mass of heavy quarks
In this work, the impact of recent measurements of heavy-flavour production
in collisions on parton distribution functions (PDFs) and their
uncertainties is studied. In this regard, the absolute and normalised cross
sections of beauty hadron production measured by LHCb at center-of-mass energy
of 7 TeV and 13 TeV are separately included in the next-to-leading order (NLO)
global QCD analysis together with the measurements of the inclusive and
heavy-flavour production cross sections at HERA. It is illustrated that the
heavy-flavour data of the LHCb experiment impose additional constraints on the
PDFs, especially on the gluon distribution at low partonic fractions of the
proton momentum. One of the most important results of the present analysis is
the significant reduction of the gluon uncertainties in the region less than
that can play a crucial rule in many areas of high energy physics
investigations.Comment: 36 pages, 8 figures, has been accepted for publication in Nuclear
Physics
Impact of intrinsic charm on PDFs with EMC and LHC data
In this contribution, we extract parton distribution functions with take into account intrinsic charm contribution and respect to nuclear effects. We focus on the impact of intrinsic charm on parton distribution functions with and without EMC and LHC data
The impact of intrinsic charm on the parton distribution functions
In this work, we present a new investigation about the impact of intrinsic
charm (IC) on the physical observables, in particular, on the heavy structure
function . Since IC distribution is dominant at large Bjorken variable
, normally, it is expected that it can be explored only at large . But,
by studying the correlation of the charm density in the proton with , we
are going to show that the IC component can also be effective at low . To
investigate further, we perform three QCD global analyses of parton
distribution functions (PDFs), by including the EMC data that are
recognized as clear evidence for existence of the intrinsic charm in the
proton, and also by considering the IC component. Although the fit of the EMC
data is extremely poor due to the data points with lower values, i.e. 0.05, but these analyses can give us new information about the impact of EMC
data and IC contribution on the behaviour of PDFs.Comment: I withdraw this paper since my supervisor require me to withdraw this
pape