# Why $$\alpha _s$$ cannot be determined from hadronic processes without simultaneously determining the parton distributions

@article{Forte2020Why\_,
title={Why \$\$\alpha \_s\$\$ cannot be determined from hadronic processes without simultaneously determining the parton distributions},
author={Stefano Forte and Zahari Kassabov},
journal={The European Physical Journal C},
year={2020}
}
• Published 14 January 2020
• Physics
• The European Physical Journal C
We show that any determination of the strong coupling $$\alpha _s$$αs from a process which depends on parton distributions, such as hadronic processes or deep-inelastic scattering, generally does not lead to a correct result unless the parton distributions (PDFs) are determined simultaneously along with $$\alpha _s$$αs. We establish the result by first showing an explicit example, and then arguing that the example is representative of a generic situation which we explain using models for the…
7 Citations
An investigation of the $$\alpha _S$$ and heavy quark mass dependence in the MSHT20 global PDF analysis
• Physics
• 2021
We investigate the MSHT20 global PDF sets, demonstrating the effects of varying the strong coupling $\alpha_S(M_Z^2)$ and the masses of the charm and bottom quarks. We determine the preferred value,
New CTEQ global analysis of quantum chromodynamics with high-precision data from the LHC
• Physics
• 2019
We present the new parton distribution functions (PDFs) from the CTEQ-TEA collaboration, obtained using a wide variety of high-precision Large Hadron Collider (LHC) data, in addition to the combined
Parton distributions need representative sampling
• Physics
• 2022
In global QCD ﬁts of parton distribution functions (PDFs), a large part of the estimated uncertainty on the PDFs originates from the choices of parametric functional forms and ﬁtting methodology. We
Parton Distributions in Nucleons and Nuclei
• Physics
Annual Review of Nuclear and Particle Science
• 2020
We review the current status of parton distribution function (PDF) determinations for unpolarized and longitudinally polarized protons and for unpolarized nuclei, which are probed by high-energy
The path to proton structure at 1% accuracy
• Computer Science
The European Physical Journal C
• 2022
A novel methodology through hyperparameter optimization is derived, leading to an efficient fitting algorithm built upon stochastic gradient descent, and a first study of the phenomenological implications of NNPDF4.0 on representative LHC processes is performed.
A new generation of simultaneous fits to LHC data using deep learning
• Physics
Journal of High Energy Physics
• 2022
Abstract We present a new methodology that is able to yield a simultaneous determination of the Parton Distribution Functions (PDFs) of the proton alongside any set of parameters that determine the
An open-source machine learning framework for global analyses of parton distributions
• Computer Science
The European Physical Journal C
• 2021
The software framework underlying the NNPDF4.0 global determination of parton distribution functions (PDFs) enables a number of phenomenological applications and the production of PDF fits under user-defined data and theory assumptions.

## References

SHOWING 1-10 OF 49 REFERENCES
Precision determination of the strong coupling constant within a global PDF analysis
• Physics
The European physical journal. C, Particles and fields
• 2018
We present a determination of the strong coupling constant $$\alpha _s(m_Z)$$αs(mZ) based on the NNPDF3.1 determination of parton distributions, which for the first time includes constraints from jet
Determination of the strong coupling constant $$\alpha _s \left( m_Z \right)$$αsmZ from measurements of the total cross section for top–antitop-quark production
• Physics
The European physical journal. C, Particles and fields
• 2017
It is presented a determination of the strong coupling constant αsmZ using inclusive top-quark pair production cross section measurements performed at the LHC and at the Tevatron with special emphasis on a consistent treatment of theoretical uncertainties and of correlations between various sources of systematic uncertainties.
Determination of the strong coupling constant $\alpha_s(M_Z)$ in next-to-next-to-leading order QCD using H1 jet cross section measurements
• R. Zlebcik
• Physics
Proceedings of XXVI International Workshop on Deep-Inelastic Scattering and Related Subjects — PoS(DIS2018)
• 2018
The strong coupling constant $\alpha_S$ is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using
Determination of the strong coupling constant $$\alpha _\mathrm {s}$$αs from transverse energy–energy correlations in multijet events at $$\sqrt{s} = 8~\hbox {TeV}$$s=8TeV using the ATLAS detector
• Physics
The European physical journal. C, Particles and fields
• 2017
Measurements of transverse energy–energy correlations and their associated asymmetries in multi-jet events using the ATLAS detector at the LHC are presented and the value of the strong coupling constant is extracted for different energy regimes.
Extraction of the strong coupling αs(mZ) from a combined NNLO analysis of inclusive electroweak boson cross sections at hadron colliders
• Physics
• 2019
The inclusive cross sections of W$^+$, W$^-$, and Z boson production from 34 different measurements performed in proton-(anti)proton collisions at center-of-mass energies $\sqrt{s}$ = 1.8--13 TeV,
Determination of the strong coupling constant using inclusive jet cross section data from multiple experiments
• Physics
The European Physical Journal C
• 2019
Inclusive jet cross section measurements from the ATLAS, CDF, CMS, D0, H1, STAR, and ZEUS experiments are explored for determinations of the strong coupling constant $$\alpha _{\text {s}} (M_{\text Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at$$\sqrt{s} = 7$$s=7$$\,\text {TeV}$$TeV • Physics • 2015 The inclusive jet cross section for proton–proton collisions at a centre-of-mass energy of 7$$\,\text {TeV}$$TeV was measured by the CMS Collaboration at the LHC with data corresponding to an Determination of the strong coupling constant$${\varvec{{\alpha _\mathrm{s} (m_\mathrm{Z})}}}$$αs(mZ) in next-to-next-to-leading order QCD using H1 jet cross section measurements • Physics • 2017 The strong coupling constant$$\alpha _\mathrm{s}$$αs is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 Measurement of multijet production in$${e\!\!\;p}$$ep collisions at high$$\varvec{Q^2}$$Q2 and determination of the strong coupling$$\varvec{{\alpha _s}} $$αs • Physics • 2015 Inclusive jet, dijet and trijet differential cross sections are measured in neutral current deep-inelastic scattering for exchanged boson virtualities$$150 < Q^2 < 15\,000\,{\mathrm
Evaluation of the strong coupling constant αS using the ATLAS inclusive jet cross-section data
• Physics
• 2012
We perform a determination of the strong coupling constant using the latest ATLAS inclusive jet cross section data, from proton–proton collisions at $\sqrt{s}=7~\mathrm{TeV}$, and their full