CMSPASSMP16005  
Measurement of the differential cross section for the production of a W ($\rightarrow \mu\nu$) boson in association with jets at $\sqrt{s} = $ 13 TeV  
CMS Collaboration  
August 2016  
Abstract: A measurement of the differential cross sections for a W ($\rightarrow \mu\nu$) boson produced in association with jets is presented. The measurement is based on the 13 TeV protonproton collisions data corresponding to an integrated luminosity of 2.5 fb$^{1}$ recorded by the CMS detector at the CERN LHC. The cross sections are reported as a function of jet multiplicity, the jet transverse momenta, the jet rapidity, and the scalar sum of the jet transverse momenta for different jet multiplicities. The measured cross sections are compared with the predictions that include multileg leading order and nexttoleading order matrix element calculations interfaced with parton showers and a nexttonexttoleading order calculation for W+1 jet.  
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These preliminary results are superseded in this paper, PRD 96 (2017) 072005. The superseded preliminary plots can be found here. 
Figures  
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Figure 1a:
Data to simulation comparison of exclusive jet multiplicity before (a) and after (b) the application of the b tag veto. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 1b:
Data to simulation comparison of exclusive jet multiplicity before (a) and after (b) the application of the b tag veto. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 2a:
Data to simulation comparison of exclusive (a) and inclusive (b) jet multiplicity. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 2b:
Data to simulation comparison of exclusive (a) and inclusive (b) jet multiplicity. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 3a:
Data to simulation comparison of $1^{st}$ (a) and $2^{nd}$ (b) jet $ {p_{\mathrm {T}}} $. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 3b:
Data to simulation comparison of $1^{st}$ (a) and $2^{nd}$ (b) jet $ {p_{\mathrm {T}}} $. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 4:
Data to simulation comparison of $3^{rd}$ jet $ {p_{\mathrm {T}}} $. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 5a:
Data to simulation comparison of exclusive (a) and inclusive (b) jet multiplicity in the $ {\mathrm {t}\overline {\mathrm {t}}} $enriched control sample. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 5b:
Data to simulation comparison of exclusive (a) and inclusive (b) jet multiplicity in the $ {\mathrm {t}\overline {\mathrm {t}}} $enriched control sample. The diboson samples (WW, WZ, and ZZ) are represented by VV. The error bars on the ratio panel represent the statistical uncertainty of the data and simulated signal sample. 
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Figure 6a:
The differential cross section measurement for the exclusive and inclusive jet multiplicities, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. Black circular markers with the grey hatched band represent the unfolded data measurement and its total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled band around MGaMC FxFx prediction represents its theoretical uncertainty including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
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Figure 6b:
The differential cross section measurement for the exclusive and inclusive jet multiplicities, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. Black circular markers with the grey hatched band represent the unfolded data measurement and its total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled band around MGaMC FxFx prediction represents its theoretical uncertainty including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
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Figure 7a:
The differential cross section measurement for the leading three jets' transverse momenta, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet transverse momentum. Black circular markers with the grey hatched band represent the unfolded data measurement and its total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
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Figure 7b:
The differential cross section measurement for the leading three jets' transverse momenta, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet transverse momentum. Black circular markers with the grey hatched band represent the unfolded data measurement and its total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
png pdf 
Figure 7c:
The differential cross section measurement for the leading three jets' transverse momenta, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet transverse momentum. Black circular markers with the grey hatched band represent the unfolded data measurement and its total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
png pdf 
Figure 8a:
The differential cross section measurement for the leading three jets' absolute rapidities, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet absolute rapidity. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
png pdf 
Figure 8b:
The differential cross section measurement for the leading three jets' absolute rapidities, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet absolute rapidity. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
png pdf 
Figure 8c:
The differential cross section measurement for the leading three jets' absolute rapidities, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the first leading jet absolute rapidity. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties including both statistical and systematical uncertainties. The lower panels show the ratios of the prediction to the unfolded data. 
png pdf 
Figure 9a:
The differential cross section measurement for $ {H_{\mathrm {T}}} $ for inclusive jet multiplicities 13, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the jets $ {H_{\mathrm {T}}} $ for one inclusive jet. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties incuding both statistical and systematical uncertainties. The lower panels show the ratio of the prediction to the unfolded data. 
png pdf 
Figure 9b:
The differential cross section measurement for $ {H_{\mathrm {T}}} $ for inclusive jet multiplicities 13, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the jets $ {H_{\mathrm {T}}} $ for one inclusive jet. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties incuding both statistical and systematical uncertainties. The lower panels show the ratio of the prediction to the unfolded data. 
png pdf 
Figure 9c:
The differential cross section measurement for $ {H_{\mathrm {T}}} $ for inclusive jet multiplicities 13, compared to the predictions of MGaMC FxFx and MGaMC, where latter denoted as MG in the legends. The NNLO prediction for W+1jet is included in the jets $ {H_{\mathrm {T}}} $ for one inclusive jet. Black circular markers with the grey hatched band represent the unfolded data measurement and total experimental uncertainty. MGaMC is given only with its statistical uncertainty. Color filled bands around MGaMC FxFx and NNLO predictions represent their theoretical uncertainties incuding both statistical and systematical uncertainties. The lower panels show the ratio of the prediction to the unfolded data. 
Tables  
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Table 1:
Number of events in data and simulation as a function of the exclusive jet multiplicity after the implementation of b tag veto. QCD background is estimated using a datadriven method. The diboson samples (WW, WZ, and ZZ) are represented by VV. 
Summary 
The first measurement of the differential cross sections for a W boson produced in association with jets in protonproton collisions at a centreofmass energy of 13 TeV is presented. The collisions data used correspond to an integrated luminosity of 2.5 fb$^{1}$ with 25 ns bunch crossing and were collected with the CMS detector during 2015 at the LHC. The differential cross sections are measured using the muon decay mode of the W boson as a function of the exclusive and the inclusive jet multiplicities up to a multiplicity of five, the jet $p_{\mathrm{T}}$ and rapidity $y$ for the three leading jets, and the jet $H_{\mathrm{T}}$ for a multiplicity up to at least three jets. The data distributions are corrected for all detector effects by means of regularised unfolding and compared with the particle level predictions by MGaMC FxFx at NLO accuracy and by MGaMC tree level at LO accuracy. The measured data is compared with a calculation at NNLO accuracy for W+1jet production. The predictions are able to describe data well on the exclusive and inclusive jet multiplicities within the uncertainties. The predictions are in good agreement with data on the jet $p_{\mathrm{T}}$ spectra. The jet $y$ and $H_{\mathrm{T}}$ spectra are well modeled by both MGaMC FxFx merged NLO prediction for all inclusive jet multiplicities and NNLO calculation for one inclusive jet. Overall, MGaMC tree level slightly underestimates data on the observables. 
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Compact Muon Solenoid LHC, CERN 