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REVIEW 2 major objections 5 minor 26 references

PDF profiling weakens high-mass Drell-Yan SMEFT bounds in a strongly flavour-dependent way, worst for first-generation quark operators.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

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2026-07-10 18:01 UTC pith:VI2GJWNO

load-bearing objection Solid, usable map of flavour-dependent PDF broadening in high-mass DY SMEFT; the hierarchy is real and the method is honest about its limits. the 2 major comments →

arxiv 2607.07791 v1 pith:VI2GJWNO submitted 2026-07-08 hep-ph

PDF effects in high-mass Drell-Yan SMEFT analyses across flavour space

David Marzocca , Manuel Morales-Alvarado This is my paper
classification hep-ph
keywords SMEFTDrell-Yanparton distribution functionsPDF profilingfour-fermion operatorsflavour dependenceHL-LHCCollins-Soper angle
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

High-mass dilepton production at the LHC is a clean place to look for contact interactions that grow with energy, but the same data also shape how we know the proton's parton densities at large momentum fraction. Those two effects can look alike: a smooth distortion of the high-mass spectrum might be new physics or just a allowed shift in the PDFs. This paper shows that the size of that confusion depends on which quark flavours the effective operators couple to. By jointly fitting SMEFT Wilson coefficients and PDF nuisance parameters on CMS high-mass data (and HL-LHC projections), the authors find the largest degradation for operators involving first-generation quarks, which ride on the high-x valence luminosities that dominate the tail. Operators with heavier quarks are less diluted. Angular binning helps separate genuine contact-interaction patterns from PDF deformations. The practical message is that PDF uncertainty cannot be treated as a uniform tax on high-energy SMEFT fits; it must be assessed flavour by flavour.

Core claim

PDF profiling induces a strongly flavour-dependent degradation of SMEFT sensitivity in high-mass Drell-Yan. With current CMS data the interval broadening is typically of order 10 percent for first-generation operators (and can reach ~46 percent for specific directions), rising to order 100 percent at the HL-LHC; second- and third-generation operators broaden only a few percent now and ~30-60 percent in the HL-LHC projection. The hierarchy tracks the high-x valence uū and dd̄ luminosities that dominate the high-mass spectrum and can partially absorb first-generation contact effects.

What carries the argument

A joint likelihood that profiles Hessian PDF nuisance parameters (from a DIS+DY prior that excludes high-mass DY) together with SMEFT Wilson coefficients, using linearised PDF shifts and linear-plus-quadratic SMEFT templates on the binned mℓℓ–cos θ* spectra; the C-Broadening_PDF factor then quantifies the widening of 95 percent CL intervals.

Load-bearing premise

The method assumes that PDF changes can be captured by linear shifts along a fixed prior Hessian basis and that mixed SMEFT-PDF terms can be neglected, which holds only when the high-mass data constrain the PDFs without rearranging them.

What would settle it

A simultaneous global PDF-plus-SMEFT fit that includes the same high-mass DY bins and allows non-linear PDF rearrangements; if the flavour hierarchy of interval broadenings disappears or reverses, the linear-Hessian claim fails.

Watch this falsifier — get emailed when new claim-graph text bears on it.

If this is right

  • High-energy SMEFT analyses that ignore flavour-dependent PDF profiling will overstate the reach of first-generation four-fermion operators relative to heavier-flavour ones.
  • HL-LHC dilepton projections that keep coarse angular bins will leave larger residual SMEFT-PDF degeneracies than analyses that retain or refine cos θ* information.
  • When first-generation SMEFT coefficients are profiled, the posterior uncertainty on high-mass uū (and to a lesser extent dd̄) luminosities can increase by up to a factor of a few relative to an SM-only PDF fit.
  • Flavour-general (lepton non-universal) fits suffer less PDF broadening than lepton-flavour-universal ones, because PDF variations are lepton-flavour blind.
  • Future experimental releases of high-mass DY should retain fine mℓℓ and angular binning if the data are to be used for simultaneous PDF-SMEFT interpretation.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same valence-driven pattern should appear in other high-x processes (high-pT jets, high-mass single-lepton plus missing energy) whenever first-generation contact operators are floated together with PDFs.
  • If charged-current high-mass data were added, the SU(2)-triplet operators that currently rely only on neutral-current information would likely show intermediate broadening between pure first-generation and pure heavy-flavour directions.
  • Scalar and tensor semileptonic operators, excluded here by the interference requirement, may exhibit a different PDF-degeneracy pattern because they lack the linear E^{2}/Λ^{2} growth that tracks the valence luminosities so closely.
  • Public posterior likelihoods that already marginalise the Hessian PDF directions would let low-energy flavour fits absorb the high-energy PDF tax without re-running the full collider analysis.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

2 major / 5 minor

Summary. The paper studies how PDF profiling affects SMEFT constraints from high-mass Drell-Yan as a function of the quark-flavour structure of semileptonic four-fermion operators. Using CMS Run-II high-mass dilepton yields and covariance (m_ℓℓ and cos θ* bins), a Hessian PDF prior built without high-mass DY, and a joint likelihood over Wilson coefficients and PDF/experimental nuisances, the authors compare fixed-PDF and PDF-profiled one- and two-parameter bounds in LFU and flavour-general scenarios, with HL-LHC Asimov projections. They report a clear flavour hierarchy: largest broadenings for first-generation operators (correlated with high-x valence uū/dd̄ luminosities), smaller effects for second- and third-generation operators, with angular binning helping to reduce SMEFT–PDF and inter-operator degeneracies. A byproduct is the degradation of posterior PDF luminosity uncertainties when SMEFT coefficients are profiled.

Significance. If the reported hierarchy holds under more complete treatments, it is a useful and actionable result for high-energy SMEFT phenomenology: PDF uncertainties cannot be treated as a uniform systematic across flavour space, and first-generation directions require joint PDF–SMEFT profiling (or complementary handles such as angular information and lepton non-universality) more urgently than heavier-flavour ones. The work complements existing simultaneous PDF–SMEFT frameworks by isolating flavour dependence with a transparent Hessian-prior setup, validates the approach against the universal (W,Y) literature, and provides public numerical intervals. The angular-information study and the PDF-side broadening diagnostics are concrete strengths that strengthen the physical interpretation beyond a pure bound-table exercise.

major comments (2)
  1. Sec. 3.2–3.3 and Eqs. (3.8)–(3.10): the analysis retains the full CMS yield covariance (which already includes a projected PDF component) while adding independent Hessian PDF nuisances, and evaluates SMEFT templates only on the central PDF (neglecting mixed SMEFT–PDF terms). The paper correctly notes that this makes absolute bounds conservative and can mildly dilute relative broadenings. Because the central claim is a quantitative flavour hierarchy of broadening factors, please quantify the size of this dilution—e.g. by a controlled comparison with a reduced covariance (or a rescaled PDF block) and/or by reporting the profiled |λ_α| ranges and residual χ² shifts—so that readers can judge whether the first- vs heavier-generation ordering could be affected at the level of the quoted percentages.
  2. Sec. 3.2 and App. A: the validity of the fixed Hessian prior is stated to require that high-mass DY constrain the prior without dominating it, with a-posteriori support from luminosity posterior bands (Figs. 5, 10). For the HL-LHC LFU case, where uū luminosity uncertainties broaden by up to ~200%, please make this check more explicit (maximum |λ_α|, comparison of prior vs posterior uncertainty envelopes in the high-x valence region, and a short statement on whether any direction saturates the linear regime). This is load-bearing for the projected O(100%) first-generation broadenings.
minor comments (5)
  1. Fig. 1 and Sec. 2: the approximate DY/non-DY background split from stacked plots is reasonable for high-mass bins, but a short sensitivity check (e.g. varying the non-DY fraction by a fixed percentage in the lowest included bins) would reassure that the hierarchy is not driven by that approximation.
  2. Sec. 2.1: HL-LHC projections keep the Run-II m_ℓℓ and cos θ* binning while rescaling luminosity and systematics. The limitation is acknowledged; it would help to state more clearly that the projected absolute sensitivities are therefore conservative relative to a finer-binned experimental analysis, while the relative PDF-broadening hierarchy is the intended message.
  3. Eq. (3.6) and surrounding text: the choice to keep linear-plus-quadratic dim-6 terms (amplitude-level truncation) is well motivated by Refs. [33,34], but a one-sentence reminder that dim-8 interference is omitted would avoid misreading the quadratic pieces as a complete O(Λ^{-4}) SMEFT prediction.
  4. App. C / Figs. 12–13: disconnected dielectron intervals and occasional narrowing after profiling are explained, but the matching procedure used for the broadening factor on multi-component intervals should be stated once in the main text or caption for reproducibility.
  5. Typographical/notation: several figure labels use `` for ℓℓ and mixed TeV^{-2} scalings; ensure consistent LaTeX (\ell\ell) and that the public results repository path mentioned in the introduction is stable and documented.

Circularity Check

1 steps flagged

No significant circularity: flavour-dependent PDF-broadening hierarchy is computed from external CMS data plus an independent (no-HM) PDF prior, not forced by definition or self-citation.

specific steps
  1. self citation load bearing [Sec. 3.2 / App. A.1 (PDF prior)]
    "For the PDF input to our computation of DY we adopt the ‘DIS+DY (no HM)’ set introduced in Ref. [11]. This is an NNPDF-style SM Monte Carlo replica fit based on DIS and Drell-Yan data, excluding the high-mass neutral-current Drell-Yan measurements… The original Monte Carlo replica set is converted into a Hessian representation, following the standard MC2Hessian construction described in App. A."

    The Hessian prior that is profiled is taken from a paper with author overlap (Morales-Alvarado). This is ordinary reuse of a published PDF set, not a load-bearing uniqueness claim or a definition that forces the flavour hierarchy; the hierarchy is still computed from the CMS likelihood. Flagged only as minor self-citation.

full rationale

The central claim (largest SMEFT-interval broadening for first-generation operators, smaller for heavier flavours) is obtained by comparing profiled vs fixed-PDF one- and two-parameter fits to public CMS high-mass dilepton yields/covariance, using SMEFT templates linear+quadratic in Wilson coefficients (Eqs. 3.4–3.6) and a linear Hessian PDF deformation of the external ‘DIS+DY (no HM)’ prior (Eqs. 3.8–3.10). Broadening is defined as the ratio of interval widths (Eq. 4.1), not as a tautology. The prior deliberately excludes the high-mass DY data under study, so the joint likelihood is not self-referential. Self-citations (chiefly Ref. [11] for the prior set and Hessian method, and literature (W,Y) benchmarks) supply inputs and validation, not the target flavour hierarchy; the hierarchy follows from the distinct partonic luminosities that weight each operator. Mild residual risk (linear Hessian + retained CMS PDF covariance) is an approximation caveat already stated by the authors, not circularity. Score 1 for ordinary methodological self-citation that is not load-bearing.

Axiom & Free-Parameter Ledger

5 free parameters · 7 axioms · 0 invented entities

The central flavour-dependent broadening claim rests on standard SMEFT and PDF technology plus several analysis choices: a fixed Hessian prior excluding high-mass DY, linear PDF and additive SMEFT+PDF response, retention of CMS systematics that already include PDFs, amplitude-level dim-6 truncation with quadratic terms, and simplified HL-LHC rescaling. No new particles or forces are invented; free parameters are the Wilson coefficients and PDF/experimental nuisance parameters profiled in the likelihood, plus the hand-chosen HL-LHC systematics improvement factor.

free parameters (5)
  • SMEFT Wilson coefficients C_x (flavour-diagonal four-fermion)
    Primary parameters of interest; profiled or scanned one/two at a time in TeV^{-2}; bounds are the paper’s output, not external inputs.
  • PDF Hessian nuisance parameters λ_α
    Gaussian unit-variance nuisances encoding prior PDF uncertainty; profiled jointly with C_x to produce the PDF-profiled bounds.
  • Experimental log-normal nuisance parameters ξ_a
    Encode CMS (and projected) correlated systematics via Σ = LL^T; profiled for every point in coefficient space.
  • r_syst (HL-LHC systematic improvement factor)
    Hand-chosen baseline r_syst = 0.2 (with r_syst = 1 as conservative check); directly rescales projected covariance and affects absolute HL-LHC widths.
  • L_HL = 6 ab^{-1} and 14 TeV energy rescaling K_I^{HL}
    Projection inputs chosen by the authors; set the Asimov yields and thus projected sensitivities.
axioms (7)
  • domain assumption Dimension-six SMEFT with Warsaw-basis semileptonic four-fermion operators that interfere with SM DY in the massless limit; scalar/tensor and FCNC operators excluded for this study.
    Section 3.1 selection criteria following Ref. [4]; defines the operator space in which flavour dependence is claimed.
  • domain assumption Linear-plus-quadratic truncation |A_SM + A_dim6|^2 is an adequate high-energy DY approximation even without dim-8 interference.
    Stated in Sec. 3.1 with citations [33,34]; used for all σ_I templates.
  • domain assumption PDF deformations relevant to high-mass DY are adequately captured by a linear Hessian representation of the ‘DIS+DY (no HM)’ Monte Carlo prior.
    Sec. 3.2 and App. A; authors note this fails if new data induce large non-linear rearrangements.
  • ad hoc to paper Mixed SMEFT–PDF terms can be neglected; SMEFT templates are evaluated on the central PDF only.
    Sec. 3.3 approximation leading to additive R_I(C,λ) in Eq. (3.10).
  • domain assumption CMS higher-order QCD/EW corrections factorise from SMEFT and PDF deformations when rescaling only the DY component of the CMS background.
    Eqs. (3.11)–(3.12) and surrounding text.
  • standard math Wilks’ theorem applies for Δχ² = 3.84 (1 dof) and 5.99 (2 dof) 95% CL intervals after profiling nuisances.
    Sec. 3.3 statistical analysis.
  • ad hoc to paper Non-DY backgrounds at HL-LHC may be rescaled with the same K-factor as DY for the high-mass bins that dominate sensitivity.
    Sec. 2.1 approximation Eq. (2.3).

pith-pipeline@v1.1.0-grok45 · 28567 in / 3983 out tokens · 44025 ms · 2026-07-10T18:01:49.001086+00:00 · methodology

0 comments
read the original abstract

High-mass Drell-Yan dilepton production provides one of the most sensitive probes of semileptonic four-fermion operators in the Standard Model Effective Field Theory (SMEFT), thanks to the energy growth of the corresponding contributions. At the same time, these measurements also constrain parton distribution functions (PDFs) in the large-$x$ region, where PDF uncertainties can mimic or obscure smooth new-physics effects. In this work we study how the impact of PDF profiling on SMEFT constraints depends on the quark-flavour structure of the effective operators, by performing a joint fit of SMEFT Wilson coefficients and PDF nuisance parameters. We find that PDF profiling induces a strongly flavour-dependent degradation of the SMEFT sensitivity, both with current data and in HL-LHC projections. The largest broadenings occur for operators involving first-generation quarks, whose effects are correlated with the high-$x$ valence-quark luminosities that dominate the high-mass spectrum. Operators involving heavier quark flavours are less affected, although with non-negligible operator-dependent variations. As a byproduct of our analysis, we obtain an estimate on the changes induced in the PDF sector by profiling SMEFT effects. We also show that angular information provides an important handle to reduce degeneracies among SMEFT directions and between SMEFT effects and allowed PDF deformations. These results demonstrate that the relevance of PDF uncertainties in high-energy SMEFT fits is not uniform across flavour space, and must be assessed in a flavour-dependent way.

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Reference graph

Works this paper leans on

26 extracted references · 26 canonical work pages · 24 internal anchors

  1. [1]

    Non-standard Charged Current Interactions: beta decays versus the LHC

    V. Cirigliano, M. Gonzalez-Alonso and M. L. Graesser,Non-standard Charged Current Interactions: beta decays versus the LHC,JHEP02(2013) 046, [1210.4553]

    work page internal anchor Pith review Pith/arXiv arXiv 2013

  2. [2]

    Global Constraints on Lepton-Quark Contact Interactions

    J. de Blas, M. Chala and J. Santiago,Global Constraints on Lepton-Quark Contact Interactions,Phys. Rev. D88(2013) 095011, [1307.5068]

    work page internal anchor Pith review Pith/arXiv arXiv 2013

  3. [3]

    Energy helps accuracy: electroweak precision tests at hadron colliders

    M. Farina, G. Panico, D. Pappadopulo, J. T. Ruderman, R. Torre and A. Wulzer,Energy helps accuracy: electroweak precision tests at hadron colliders,Phys. Lett. B772(2017) 210–215, [1609.08157]

    work page internal anchor Pith review Pith/arXiv arXiv 2017

  4. [4]

    High-$p_T$ dilepton tails and flavour physics

    A. Greljo and D. Marzocca,High-pT dilepton tails and flavor physics,Eur. Phys. J. C77 (2017) 548, [1704.09015]

    work page internal anchor Pith review Pith/arXiv arXiv 2017

  5. [5]

    Charm Physics Confronts High-$p_T$ Lepton Tails

    J. Fuentes-Martin, A. Greljo, J. Martin Camalich and J. D. Ruiz-Alvarez,Charm physics confronts high-pT lepton tails,JHEP11(2020) 080, [2003.12421]

    work page internal anchor Pith review Pith/arXiv arXiv 2020

  6. [6]

    On the W&Y interpretation of high-energy Drell-Yan measurements

    R. Torre, L. Ricci and A. Wulzer,On the W&Y interpretation of high-energy Drell-Yan measurements,JHEP02(2021) 144, [2008.12978]

    work page internal anchor Pith review Pith/arXiv arXiv 2021

  7. [7]

    HighPT: A Tool for high-$p_T$ Drell-Yan Tails Beyond the Standard Model

    L. Allwicher, D. A. Faroughy, F. Jaffredo, O. Sumensari and F. Wilsch,HighPT: A tool for high-p T Drell-Yan tails beyond the standard model,Comput. Phys. Commun.289(2023) 108749, [2207.10756]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  8. [8]

    Drell-Yan Tails Beyond the Standard Model

    L. Allwicher, D. A. Faroughy, F. Jaffredo, O. Sumensari and F. Wilsch,Drell-Yan tails beyond the Standard Model,JHEP03(2023) 064, [2207.10714]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  9. [9]

    Rare $b$ decays meet high-mass Drell-Yan

    A. Greljo, J. Salko, A. Smolkovič and P. Stangl,Rare b decays meet high-mass Drell-Yan, JHEP05(2023) 087, [2212.10497]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  10. [10]

    Can New Physics hide inside the proton?

    S. Carrazza, C. Degrande, S. Iranipour, J. Rojo and M. Ubiali,Can New Physics hide inside the proton?,Phys. Rev. Lett.123(2019) 132001, [1905.05215]

    work page internal anchor Pith review Pith/arXiv arXiv 2019

  11. [11]

    Parton distributions in the SMEFT from high-energy Drell-Yan tails

    A. Greljo, S. Iranipour, Z. Kassabov, M. Madigan, J. Moore, J. Rojo et al.,Parton distributions in the SMEFT from high-energy Drell-Yan tails,JHEP07(2021) 122, [2104.02723]. [12]CMScollaboration, A. Tumasyan et al.,Measurement and QCD analysis of double-differential inclusive jet cross sections in proton-proton collisions at√s= 13 TeV, JHEP02(2022) 142, [...

    work page internal anchor Pith review Pith/arXiv arXiv 2021

  12. [12]

    A new generation of simultaneous fits to LHC data using deep learning

    S. Iranipour and M. Ubiali,A new generation of simultaneous fits to LHC data using deep learning,JHEP05(2022) 032, [2201.07240]

    work page internal anchor Pith review Pith/arXiv arXiv 2022

  13. [13]

    J. Gao, M. Gao, T. J. Hobbs, D. Liu and X. Shen,Simultaneous CTEQ-TEA extraction of PDFs and SMEFT parameters from jet andttdata,JHEP05(2023) 003, [2211.01094]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  14. [14]

    The top quark legacy of the LHC Run II for PDF and SMEFT analyses

    Z. Kassabov, M. Madigan, L. Mantani, J. Moore, M. Morales Alvarado, J. Rojo et al.,The top quark legacy of the LHC Run II for PDF and SMEFT analyses,JHEP05(2023) 205, [2303.06159]

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  15. [15]

    Hide and seek: how PDFs can conceal New Physics

    E. Hammou, Z. Kassabov, M. Madigan, M. L. Mangano, L. Mantani, J. Moore et al.,Hide and seek: how PDFs can conceal new physics,JHEP11(2023) 090, [2307.10370]. [17]PBSPcollaboration, M. N. Costantini, E. Hammou, Z. Kassabov, M. Madigan, L. Mantani, M. Morales Alvarado et al.,SIMUnet: an open-source tool for simultaneous global fits of EFT Wilson coefficien...

    work page internal anchor Pith review Pith/arXiv arXiv 2023

  16. [16]

    E. Cole, M. N. Costantini, E. Hammou, L. Mantani, F. Merlotti, M. Morales-Alvarado et al., Tailored PDFs for New Physics searches,2602.20235. [19]ATLAScollaboration, G. Aad et al.,Measurement of the high-mass Drell–Yan differential cross-section in pp collisions at sqrt(s)=7 TeV with the ATLAS detector,Phys. Lett. B725 (2013) 223–242, [1305.4192]. [20]CMS...

    work page arXiv 2013

  17. [17]

    Asymptotic formulae for likelihood-based tests of new physics

    G. Cowan, K. Cranmer, E. Gross and O. Vitells,Asymptotic formulae for likelihood-based tests of new physics,Eur. Phys. J. C71(2011) 1554, [1007.1727]. [Erratum: Eur.Phys.J.C 73, 2501 (2013)]

    work page internal anchor Pith review Pith/arXiv arXiv 2011

  18. [18]

    Dimension-Six Terms in the Standard Model Lagrangian

    B. Grzadkowski, M. Iskrzynski, M. Misiak and J. Rosiek,Dimension-Six Terms in the Standard Model Lagrangian,JHEP10(2010) 085, [1008.4884]

    work page internal anchor Pith review Pith/arXiv arXiv 2010

  19. [19]

    Glioti, D

    A. Glioti, D. Marzocca and A. Wulzer,Flavor physics at high-energy muon colliders,JHEP 12(2025) 152, [2509.08132]

    work page arXiv 2025

  20. [20]

    On the EFT validity for Drell-Yan tails at the LHC

    L. Allwicher, D. A. Faroughy, M. Martines, O. Sumensari and F. Wilsch,On the EFT validity for Drell–Yan tails at the LHC,Eur. Phys. J. C85(2025) 463, [2412.14162]. – 32 –

    work page internal anchor Pith review Pith/arXiv arXiv 2025

  21. [21]

    Truncation, validity, uncertainties

    I. Brivio et al.,Truncation, validity, uncertainties,2201.04974. [35]NNPDFcollaboration, R. D. Ball et al.,The path to proton structure at 1% accuracy,Eur. Phys. J. C82(2022) 428, [2109.02653]

    work page internal anchor Pith review Pith/arXiv arXiv 2022

  22. [22]

    Unravelling New Physics Signals at the HL-LHC with Low-Energy Constraints

    E. Hammou and M. Ubiali,Unravelling new physics signals at the HL-LHC with EIC and FPF constraints,Phys. Rev. D111(2025) 095028, [2410.00963]

    work page internal anchor Pith review Pith/arXiv arXiv 2025

  23. [23]

    Electroweak symmetry breaking after LEP1 and LEP2

    R. Barbieri, A. Pomarol, R. Rattazzi and A. Strumia,Electroweak symmetry breaking after LEP-1 and LEP-2,Nucl. Phys. B703(2004) 127–146, [hep-ph/0405040]

    work page internal anchor Pith review Pith/arXiv arXiv 2004

  24. [24]

    An Unbiased Hessian Representation for Monte Carlo PDFs

    S. Carrazza, S. Forte, Z. Kassabov, J. I. Latorre and J. Rojo,An Unbiased Hessian Representation for Monte Carlo PDFs,Eur. Phys. J. C75(2015) 369, [1505.06736]

    work page internal anchor Pith review Pith/arXiv arXiv 2015

  25. [25]

    Specialized minimal PDFs for optimized LHC calculations

    S. Carrazza, S. Forte, Z. Kassabov and J. Rojo,Specialized minimal PDFs for optimized LHC calculations,Eur. Phys. J. C76(2016) 205, [1602.00005]

    work page internal anchor Pith review Pith/arXiv arXiv 2016

  26. [26]

    LHAPDF6: parton density access in the LHC precision era

    A. Buckley, J. Ferrando, S. Lloyd, K. Nordström, B. Page, M. Rüfenacht et al.,LHAPDF6: parton density access in the LHC precision era,Eur. Phys. J. C75(2015) 132, [1412.7420]. – 33 –

    work page internal anchor Pith review Pith/arXiv arXiv 2015