137 research outputs found
Investigation of High Energy Behaviour of HERA Data
We analyse the high precision HERA data in the low- regions,
and the very-low-, , regions using -Fits.
is a measure of the rate of rise of defined by . We show that determined in these two regions, at
various values, is systematically smaller in the very-low- region as
compared to the low- region. We discuss some possible physical
interpretations of this effect.Comment: 19 pages, 10 figure
Dipole model analysis of highest precision HERA data, including very low 's
We analyse, within a dipole model, the final, inclusive HERA DIS cross
section data in the low region, using fully correlated errors. We show,
that these highest precision data are very well described within the dipole
model framework starting from values of 3.5 GeV to the highest values
of 250 GeV.Comment: 16 pages, 4 figures. arXiv admin note: text overlap with
arXiv:1312.406
A determination of mc(mc) from HERA data using a matched heavy-flavor scheme
The charm quark mass is one of the fundamental parameters of the Standard
Model Lagrangian. In this work we present a determination of the MSbar charm
mass from a fit to the inclusive and charm HERA deep-inelastic structure
function data. The analysis is performed within the xFitter framework, with
structure functions computed in the FONLL general-mass scheme as implemented in
APFEL. In the case of the FONLL-C scheme, we obtain mc(mc) = 1.335 +-
0.043(exp) +0.019 -0.000(param) +0.011 -0.008(mod) +0.033 -0.008(th) GeV. We
also perform an analogous determination in the fixed-flavor-number scheme at
next-to-leading order, finding mc(mc) = 1.318 +- 0.054(exp) +0.011
-0.010(param) +0.015 -0.019(mod) +0.045 -0.004(th) GeV, compatible with the
FONLL-C value. Our results are consistent with previous determinations from DIS
data as well as with the PDG world average.Comment: 37 pages, 12 figures, 3 table
Parton Distribution Functions of the Charged Pion Within The xFitter Framework
We present the first open-source analysis of parton distribution functions
(PDFs) of charged pions using xFitter, an open-source QCD fit framework to
facilitate PDF extraction and analyses. Our calculations are implemented at
next-to-leading order (NLO) using APPLgrids generated by MCFM generator. Using
currently available Drell-Yan and photon production data, we find the valence
distribution is well constrained; however, the considered data are not
sensitive enough to unambiguously determine sea and gluon distributions.
Fractions of momentum carried by the valence, sea and gluon components are
discussed, and we compare with the results of JAM collaboration and the GRV
group.Comment: 9 pages, 6 figure
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