CMS-PAS-HIG-18-005 | ||

Search for a heavy pseudoscalar boson decaying to a Z boson and a Higgs boson at $ \sqrt{s} = $ 13 TeV | ||

CMS Collaboration | ||

July 2018 | ||

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Abstract:
A search for a heavy pseudoscalar boson A decaying into a Z boson and the standard model Higgs boson is presented. In the considered final state, the Higgs boson decays to a b quark-antiquark, and the Z boson decays either into a pair of electrons, muons, or neutrinos. The analysis is performed using a data sample corresponding to an integrated luminosity of 35.9 fb$^{-1}$ collected in 2016 by the CMS experiment at the CERN LHC from proton-proton collisions at a center-of-mass energy of 13 TeV. The data are found to be consistent with the background expectations. Exclusion limits are set in the context of two Higgs doublet models in the mass range between 225 and 1000 GeV.
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Links:
CDS record (PDF) ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, JHEP 06 (2019) 143.The superseded preliminary plots can be found here. |

Figures | |

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Figure 1:
Feynman diagrams of the production in the 2HDM of a pseudoscalar A boson through gluon-gluon fusion (left), and with accompanying b quarks (right). |

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Figure 1-a:
Feynman diagrams of the production in the 2HDM of a pseudoscalar A boson through gluon-gluon fusion (left), and with accompanying b quarks (right). |

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Figure 1-b:
Feynman diagrams of the production in the 2HDM of a pseudoscalar A boson through gluon-gluon fusion (left), and with accompanying b quarks (right). |

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Figure 2:
Signal acceptance times efficiency for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$. The number of events passing the signal region selections is denoted as $N^{SR}$, and $N^{GEN}$ is the number of events generated before applying any selection. |

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Figure 2-a:
Signal acceptance times efficiency for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$. The number of events passing the signal region selections is denoted as $N^{SR}$, and $N^{GEN}$ is the number of events generated before applying any selection. |

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Figure 2-b:
Signal acceptance times efficiency for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$. The number of events passing the signal region selections is denoted as $N^{SR}$, and $N^{GEN}$ is the number of events generated before applying any selection. |

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Figure 3:
Pre- (dashed gray lines) and post-fit (stacked histograms) number of events in the different control regions used in the fit. |

png pdf |
Figure 4:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-a:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-b:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-c:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-d:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-e:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 4-f:
Distributions of the ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ variable in the $0\ell $ categories (left) and ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ in the $2\ell $ categories (right), in the 1 b tag (upper), 2 b tag (center), and 3 b tag (lower) SRs. In the $2\ell $ categories, the contribution of the $2 {\mathrm {e}}$ and $2\mu $ channels have been summed. The gray dotted line represents the sum of the background before the fit; the shaded area represents the post-fit uncertainty. The hatched red histograms represent signal produced in association with b quarks and corresponding to $\sigma _{{\mathrm {A}}} {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})= $ 0.1 pb. The bottom panels depict the pulls in each bin, $(N^\text {data}-N^\text {bkg})/\sigma $, where $\sigma $ is the statistical uncertainty in data. |

png pdf |
Figure 5:
Observed and expected 95% CL upper limit on $\sigma _ {\mathrm {A}} \, {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}})\, {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})$ for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$ in the narrow-width approximation, including all statistical and systematic uncertainties. The solid curves and their shaded areas correspond to the product of the cross sections and the branching fractions and the relative uncertainties predicted by the 2HDM Type-I and Type-II for the arbitrary parameters $\tan\beta =$ 3 and $ {\cos(\beta -\alpha)} =$ 0.1. |

png pdf |
Figure 5-a:
Observed and expected 95% CL upper limit on $\sigma _ {\mathrm {A}} \, {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}})\, {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})$ for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$ in the narrow-width approximation, including all statistical and systematic uncertainties. The solid curves and their shaded areas correspond to the product of the cross sections and the branching fractions and the relative uncertainties predicted by the 2HDM Type-I and Type-II for the arbitrary parameters $\tan\beta =$ 3 and $ {\cos(\beta -\alpha)} =$ 0.1. |

png pdf |
Figure 5-b:
Observed and expected 95% CL upper limit on $\sigma _ {\mathrm {A}} \, {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}})\, {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})$ for an A boson produced through gluon-gluon fusion (left) and b quark association (right) as a function of ${m_{{\mathrm {A}}}}$ in the narrow-width approximation, including all statistical and systematic uncertainties. The solid curves and their shaded areas correspond to the product of the cross sections and the branching fractions and the relative uncertainties predicted by the 2HDM Type-I and Type-II for the arbitrary parameters $\tan\beta =$ 3 and $ {\cos(\beta -\alpha)} =$ 0.1. |

png pdf |
Figure 6:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${\tan\beta}$ and ${\cos(\beta -\alpha)}$. Contours are derived from the projection on the 2HDM parameter space for the ${m_{{\mathrm {A}}}} = $ 300 GeV signal hypothesis. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 6-a:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${\tan\beta}$ and ${\cos(\beta -\alpha)}$. Contours are derived from the projection on the 2HDM parameter space for the ${m_{{\mathrm {A}}}} = $ 300 GeV signal hypothesis. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 6-b:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${\tan\beta}$ and ${\cos(\beta -\alpha)}$. Contours are derived from the projection on the 2HDM parameter space for the ${m_{{\mathrm {A}}}} = $ 300 GeV signal hypothesis. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 6-c:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${\tan\beta}$ and ${\cos(\beta -\alpha)}$. Contours are derived from the projection on the 2HDM parameter space for the ${m_{{\mathrm {A}}}} = $ 300 GeV signal hypothesis. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 6-d:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${\tan\beta}$ and ${\cos(\beta -\alpha)}$. Contours are derived from the projection on the 2HDM parameter space for the ${m_{{\mathrm {A}}}} = $ 300 GeV signal hypothesis. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 7:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${m_{{\mathrm {A}}}}$, fixing $ {\cos(\beta -\alpha)} = $ 0.1. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 7-a:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${m_{{\mathrm {A}}}}$, fixing $ {\cos(\beta -\alpha)} = $ 0.1. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 7-b:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${m_{{\mathrm {A}}}}$, fixing $ {\cos(\beta -\alpha)} = $ 0.1. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 7-c:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${m_{{\mathrm {A}}}}$, fixing $ {\cos(\beta -\alpha)} = $ 0.1. The excluded area is represented by the shaded gray area. |

png pdf |
Figure 7-d:
Observed and expected (with ${\pm}$1, 2$\sigma $ uncertainty bands) exclusion limit for Type-I (top left), Type-II (top right), flipped (bottom left), lepton-specific (bottom right) models, as a function of ${m_{{\mathrm {A}}}}$, fixing $ {\cos(\beta -\alpha)} = $ 0.1. The excluded area is represented by the shaded gray area. |

Tables | |

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Table 1:
Summary of statistical and systematic uncertainties for backgrounds and signals. The uncertainties marked are also propagated to the ${m_{{\mathrm {Z}} {\mathrm {h}}}}$ and ${m_{{\mathrm {Z}} {\mathrm {h}}}^\mathrm {T}}$ distributions. |

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Table 2:
Corrective factors for the main backgrounds, as derived by the combined fit in the background-only hypothesis, with respect to the event yield from simulated samples. |

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Table 3:
Expected and observed event yields after the fit in the signal regions. The dielectron and dimuon categories are summed together. The single dash symbol represents backgrounds with no simulated events passing the selections. The signal yields refer to pre-fit values corresponding to a cross section of 0.1 pb (gluon-gluon fusion for $ {m_{{\mathrm {A}}}} = $ 300 GeV, and b quark associated for $ {m_{{\mathrm {A}}}} = $ 1000 GeV) multiplied by $ {\mathcal {B}}({\mathrm {A}} \to {\mathrm {Z}} {\mathrm {h}}) \, {\mathcal {B}}({\mathrm {h}} \to {{\mathrm {b}} {\overline {\mathrm {b}}}})$. |

Summary |

A search is presented in the context of an extended Higgs boson sector for a heavy pseudoscalar boson A that decays into a Z boson and a SM h boson, with the Z boson decaying into electrons, muons, or neutrinos, and the h boson into $\mathrm{b\bar{b}}.$ The standard model backgrounds are suppressed by using the characteristics of the considered signal, namely the production and decay angles of the A , Z, and h bosons, and by improving the A mass resolution. No excess is observed and upper limits at a 95% CL are set on the A boson cross section in either the gluon-gluon fusion or b quark associated production and the branching fractions $\sigma_\mathrm{A} \,{\mathcal{B}}(\mathrm{A} \to\mathrm{Z}\mathrm{h}) \,{\mathcal{B}}(\mathrm{h}\to\mathrm{b\bar{b}})$, which exclude 1 to 0.01 pb at the lower and upper ends of the 250-1000 GeV mass range. Interpretations are given in the context of Type-I, Type-II, flipped, and lepton-specific 2HDM formulations, thereby reducing the parameter space for extensions of the standard model. |

References | ||||

1 |
ATLAS Collaboration |
Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC | PLB 716 (2012) 1 | 1207.7214 |

2 |
CMS Collaboration |
Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC | PLB 716 (2012) 30 | CMS-HIG-12-0281207.7235 |

3 |
CMS Collaboration |
Observation of a new boson with mass near 125 GeV in pp collisions at $ \sqrt{s} = $ 7 and 8 TeV | JHEP 06 (2013) 081 | CMS-HIG-12-0361303.4571 |

4 |
ATLAS Collaboration |
Measurement of the Higgs boson mass from the $ H\rightarrow{}\gamma{}\gamma{} $ and $ H\rightarrow{}Z{Z}^{*}\rightarrow{}4\ell{} $ channels in pp collisions at center-of-mass energies of 7 and 8~TeV with the ATLAS detector | PRD 90 (2014) 052004 | 1406.3827 |

5 |
CMS Collaboration |
Precise determination of the mass of the Higgs boson and tests of compatibility of its couplings with the standard model predictions using proton collisions at 7 and 8 TeV | EPJC 75 (2015) 212 | CMS-HIG-14-0091412.8662 |

6 |
CMS Collaboration |
Evidence for the direct decay of the 125 GeV Higgs boson to fermions | NP 10 (2014) 557 | CMS-HIG-13-0331401.6527 |

7 |
ATLAS and CMS Collaborations | Combined measurement of the Higgs boson mass in pp collisions at $ \sqrt{s}= $ 7 and 8 TeV with the ATLAS and CMS experiments | PRL 114 (2015) 191803 | 1503.07589 |

8 |
G. C. Branco et al. | Theory and phenomenology of two-Higgs-doublet models | Phys. Rep. 516 (2012) 1 | 1106.0034 |

9 |
CMS Collaboration |
Combined measurements of the Higgs boson's couplings at $ \sqrt{s}= $ 13 TeV | CMS-PAS-HIG-17-031 | CMS-PAS-HIG-17-031 |

10 |
CMS Collaboration |
Search for a pseudoscalar boson decaying into a Z boson and the 125 GeV Higgs boson in $ \ell^+\ell^- b\overline{b} $ final states | PLB 748 (2015) 221 | CMS-HIG-14-0111504.04710 |

11 |
ATLAS Collaboration |
Search for heavy resonances decaying into a W or Z boson and a Higgs boson in final states with leptons and b-jets in 36 fb$ ^{-1} $ of $ \sqrt s = $ 13 TeV pp collisions with the ATLAS detector | Submitted to JHEP | 1712.06518 |

12 |
CMS Collaboration |
The CMS experiment at the CERN LHC | JINST 3 (2008) S08004 | CMS-00-001 |

13 |
CMS Collaboration |
Description and performance of track and primary-vertex reconstruction with the CMS tracker | JINST 9 (2014) P10009 | CMS-TRK-11-0011405.6569 |

14 |
CMS Collaboration |
Performance of CMS muon reconstruction in pp collision events at $ \sqrt{s}= $ 7 TeV | JINST 7 (2012) P10002 | CMS-MUO-10-0041206.4071 |

15 |
CMS Collaboration |
The CMS trigger system | JINST 12 (2017) P01020 | CMS-TRG-12-0011609.02366 |

16 |
CMS Collaboration |
Particle-flow reconstruction and global event description with the cms detector | JINST 12 (2017) P10003 | CMS-PRF-14-0011706.04965 |

17 |
CMS Collaboration |
Pileup removal algorithms | CMS-PAS-JME-14-001 | CMS-PAS-JME-14-001 |

18 |
CMS Collaboration |
Performance of electron reconstruction and selection with the CMS detector in proton-proton collisions at $ \sqrt{s} = $ 8 TeV | JINST 10 (2015) P06005 | CMS-EGM-13-0011502.02701 |

19 |
CMS Collaboration |
Reconstruction and identification of $ \tau $ lepton decays to hadrons and $ \nu_\tau $ at CMS | JINST 11 (2016) P01019 | CMS-TAU-14-0011510.07488 |

20 |
M. Cacciari, G. P. Salam, and G. Soyez | The anti-$ k_\text{t} $ jet clustering algorithm | JHEP 04 (2008) 063 | 0802.1189 |

21 |
M. Cacciari, G. P. Salam, and G. Soyez | FastJet user manual | EPJC 72 (2012) 1896 | 1111.6097 |

22 |
M. Cacciari, G. P. Salam, and G. Soyez | The catchment area of jets | JHEP 04 (2008) 005 | 0802.1188 |

23 |
CMS Collaboration |
Jet energy scale and resolution in the CMS experiment in pp collisions at 8 TeV | JINST 12 (2017) P02014 | CMS-JME-13-0041607.03663 |

24 |
CMS Collaboration |
Identification of heavy-flavour jets with the CMS detector in pp collisions at 13 TeV | JINST 13 (2018) P05011 | CMS-BTV-16-0021712.07158 |

25 |
J. Alwall et al. | The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations | JHEP 07 (2014) 079 | 1405.0301 |

26 |
Y. Li and F. Petriello | Combining QCD and electroweak corrections to dilepton production in FEWZ | PRD 86 (2012) 094034 | 1208.5967 |

27 |
S. Kallweit et al. | NLO QCD+EW predictions for V+jets including off-shell vector-boson decays and multijet merging | JHEP 04 (2016) 021 | 1511.08692 |

28 |
P. Nason | A new method for combining NLO QCD with shower Monte Carlo algorithms | JHEP 11 (2004) 040 | hep-ph/0409146 |

29 |
S. Frixione, P. Nason, and C. Oleari | Matching NLO QCD computations with Parton Shower simulations: the POWHEG method | JHEP 11 (2007) 070 | 0709.2092 |

30 |
S. Alioli, P. Nason, C. Oleari, and E. Re | A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX | JHEP 06 (2010) 043 | 1002.2581 |

31 |
M. Czakon and A. Mitov | Top++: A program for the calculation of the top-pair cross-section at hadron colliders | CPC 185 (2014) 2930 | 1112.5675 |

32 |
CMS Collaboration |
Measurement of differential cross sections for top quark pair production using the lepton+jets final state in proton-proton collisions at 13 TeV | PRD 95 (2017) 092001 | CMS-TOP-16-0081610.04191 |

33 |
R. Frederix and S. Frixione | Merging meets matching in MC@NLO | JHEP 12 (2012) 061 | 1209.6215 |

34 |
NNPDF Collaboration | Parton distributions for the LHC Run II | JHEP 04 (2015) 040 | 1410.8849 |

35 |
T. Sjostrand, S. Mrenna, and P. Skands | A brief introduction to PYTHIA 8.1 | CPC 178 (2008) 852 | 0710.3820 |

36 |
T. Sjostrand, S. Mrenna, and P. Skands | PYTHIA 6.4 physics and manual | JHEP 05 (2006) 026 | hep-ph/0603175 |

37 |
P. Skands, S. Carrazza, and J. Rojo | Tuning PYTHIA 8.1: the Monash 2013 Tune | EPJC 74 (2014) 3024 | 1404.5630 |

38 |
CMS Collaboration |
Event generator tunes obtained from underlying event and multiparton scattering measurements | EPJC 76 (2016) 155 | CMS-GEN-14-0011512.00815 |

39 |
CMS Collaboration |
Investigations of the impact of the parton shower tuning in Pythia 8 in the modelling of $ \mathrm{t\overline{t}} $ at $ \sqrt{s}= $ 8 and 13 TeV | CMS-PAS-TOP-16-021 | CMS-PAS-TOP-16-021 |

40 |
GEANT4 Collaboration | GEANT4---a simulation toolkit | NIMA 506 (2003) 250 | |

41 |
J. Butterworth et al. | PDF4LHC recommendations for LHC Run II | JPG 43 (2016) 23001 | 1510.03865 |

42 |
A. Kalogeropoulos and J. Alwall | The SysCalc code: A tool to derive theoretical systematic uncertainties | 1801.08401 | |

43 |
CMS Collaboration |
CMS Luminosity Measurement for the 2016 Data Taking Period | CDS | |

44 |
R. Barlow and C. Beeston | Fitting using finite Monte Carlo samples | CPC 77 (1993) 219 | |

45 |
T. Junk | Confidence level computation for combining searches with small statistics | NIMA 434 (1999) 435 | hep-ex/9902006 |

46 |
A. L. Read | Presentation of search results: the $ CL_s $ technique | JPG 28 (2002) 2693 | |

47 |
CMS and ATLAS Collaborations | Procedure for the LHC Higgs boson search combination in Summer 2011 | CMS-NOTE-2011-005 | |

48 |
G. Cowan, K. Cranmer, E. Gross, and O. Vitells | Asymptotic formulae for likelihood-based tests of new physics | EPJC 71 (2011) 1554 | 1007.1727 |

49 |
D. Eriksson, J. Rathsman, and O. St\aal | 2HDMC --- two-Higgs-doublet model calculator physics and manual | CPC 181 (2010) 189 | 0902.0851 |

50 |
R. V. Harlander, S. Liebler, and H. Mantler | SusHi: A program for the calculation of Higgs production in gluon fusion and bottom-quark annihilation in the Standard Model and the MSSM | CPC 184 (2013) 1605 | 1212.3249 |

51 |
Particle Data Group, J. Beringer et al. | Review of Particle Physics | PRD 86 (2012) 010001 |

Compact Muon Solenoid LHC, CERN |