Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data

NNPDF Collaboration; Richard D. Ball; Valerio Begone; Francesco Cerutti; Luigi Del Debbio; Stefano Forte; Alberto Guffanti; Nathan P. Hartland; Jose I. Latorre; Juan Rojo; Maria Ubiali

doi:10.1016/j.nuclphysb.2011.10.018

Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data

NNPDF Collaboration, Richard D. Ball, Valerio Begone, Francesco Cerutti, Luigi Del Debbio, Stefano Forte, Alberto Guffanti, Nathan P. Hartland, Jose I. Latorre, Juan Rojo, Maria Ubiali

School of Physics and Astronomy

Research output: Contribution to journal › Article › peer-review

Abstract / Description of output

We develop in more detail our reweighting method for incorporating new datasets in parton fits based on a Monte Carlo representation of PDFs. After revisiting the derivation of the reweighting formula, we show how to construct an unweighted PDF replica set which is statistically equivalent to a given reweighted set. We then use reweighting followed by unweighting to test the consistency of the method, specifically by verifying that results do not depend on the order in which new data are included in the fit via reweighting. We apply the reweighting method to study the impact of LHC W lepton asymmetry data on the NNPDF2.1 set. We show how these data reduce the PDF uncertainties of light quarks in the medium and small x region, providing the first solid constraints on PDFs from LHC data. (C) 2011 Elsevier B.V. All rights reserved.

Original language	English
Pages (from-to)	608-638
Number of pages	31
Journal	Nuclear physics b
Volume	855
Issue number	3
DOIs	https://doi.org/10.1016/j.nuclphysb.2011.10.018
Publication status	Published - 21 Feb 2012

Keywords / Materials (for Non-textual outputs)

Parton distribution functions
W lepton asymmetry data
PROTON

Access to Document

10.1016/j.nuclphysb.2011.10.018

Cite this

@article{2db1e9e445504d799fd57262a6229d41,

title = "Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data",

abstract = "We develop in more detail our reweighting method for incorporating new datasets in parton fits based on a Monte Carlo representation of PDFs. After revisiting the derivation of the reweighting formula, we show how to construct an unweighted PDF replica set which is statistically equivalent to a given reweighted set. We then use reweighting followed by unweighting to test the consistency of the method, specifically by verifying that results do not depend on the order in which new data are included in the fit via reweighting. We apply the reweighting method to study the impact of LHC W lepton asymmetry data on the NNPDF2.1 set. We show how these data reduce the PDF uncertainties of light quarks in the medium and small x region, providing the first solid constraints on PDFs from LHC data. (C) 2011 Elsevier B.V. All rights reserved.",

keywords = "Parton distribution functions, W lepton asymmetry data, PROTON",

author = "{NNPDF Collaboration} and Ball, {Richard D.} and Valerio Begone and Francesco Cerutti and {Del Debbio}, Luigi and Stefano Forte and Alberto Guffanti and Hartland, {Nathan P.} and Latorre, {Jose I.} and Juan Rojo and Maria Ubiali",

year = "2012",

month = feb,

day = "21",

doi = "10.1016/j.nuclphysb.2011.10.018",

language = "English",

volume = "855",

pages = "608--638",

journal = "Nuclear physics b",

issn = "0550-3213",

publisher = "Elsevier",

number = "3",

}

TY - JOUR

T1 - Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data

AU - NNPDF Collaboration

AU - Ball, Richard D.

AU - Begone, Valerio

AU - Cerutti, Francesco

AU - Del Debbio, Luigi

AU - Forte, Stefano

AU - Guffanti, Alberto

AU - Hartland, Nathan P.

AU - Latorre, Jose I.

AU - Rojo, Juan

AU - Ubiali, Maria

PY - 2012/2/21

Y1 - 2012/2/21

N2 - We develop in more detail our reweighting method for incorporating new datasets in parton fits based on a Monte Carlo representation of PDFs. After revisiting the derivation of the reweighting formula, we show how to construct an unweighted PDF replica set which is statistically equivalent to a given reweighted set. We then use reweighting followed by unweighting to test the consistency of the method, specifically by verifying that results do not depend on the order in which new data are included in the fit via reweighting. We apply the reweighting method to study the impact of LHC W lepton asymmetry data on the NNPDF2.1 set. We show how these data reduce the PDF uncertainties of light quarks in the medium and small x region, providing the first solid constraints on PDFs from LHC data. (C) 2011 Elsevier B.V. All rights reserved.

AB - We develop in more detail our reweighting method for incorporating new datasets in parton fits based on a Monte Carlo representation of PDFs. After revisiting the derivation of the reweighting formula, we show how to construct an unweighted PDF replica set which is statistically equivalent to a given reweighted set. We then use reweighting followed by unweighting to test the consistency of the method, specifically by verifying that results do not depend on the order in which new data are included in the fit via reweighting. We apply the reweighting method to study the impact of LHC W lepton asymmetry data on the NNPDF2.1 set. We show how these data reduce the PDF uncertainties of light quarks in the medium and small x region, providing the first solid constraints on PDFs from LHC data. (C) 2011 Elsevier B.V. All rights reserved.

KW - Parton distribution functions

KW - W lepton asymmetry data

KW - PROTON

UR - http://www.scopus.com/inward/record.url?scp=82555187122&partnerID=8YFLogxK

U2 - 10.1016/j.nuclphysb.2011.10.018

DO - 10.1016/j.nuclphysb.2011.10.018

M3 - Article

SN - 0550-3213

VL - 855

SP - 608

EP - 638

JO - Nuclear physics b

JF - Nuclear physics b

IS - 3

ER -

Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data

Abstract / Description of output

Keywords / Materials (for Non-textual outputs)

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Particle Theory at the Tait Institute

Cite this

Reweighting and unweighting of parton distributions and the LHC W lepton asymmetry data

Abstract / Description of output

Keywords / Materials (for Non-textual outputs)

Access to Document

Other files and links

Fingerprint

Projects

Particle Theory at the Tait Institute

Cite this