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| CMS-EXO-23-010 ; CERN-EP-2025-044 | ||
| Search for nonresonant new physics signals in high-mass dilepton events produced in association with b-tagged jets in proton-proton collisions at $ \sqrt{s} = $ 13 TeV | ||
| CMS Collaboration | ||
| 16 June 2025 | ||
| Submitted to J. High Energy Phys. | ||
| Abstract: A search for nonresonant new physics phenomena in high-mass dilepton events produced in association with b-tagged jets is performed using proton-proton collision data collected in 2016-2018 by the CMS experiment at the CERN LHC, at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb$ ^{-1} $. The analysis considers two effective field theory models with dimension-six operators; involving four-fermion contact interactions between two leptons ($ \ell\ell $, electrons or muons) and b or s quarks ($ \mathrm{b}\mathrm{b}\ell\ell $ and $ \mathrm{b}\mathrm{s}\ell\ell $). Two lepton flavor combinations ($ \mathrm{e}\mathrm{e} $ and $ \mu\mu $) are required and events are classified as having 0, 1, and $ \geq $2 b-tagged jets in the final state. No significant excess is observed over the standard model backgrounds. Upper limits are set on the production cross section of the new physics signals. These translate into lower limits on the energy scale $ \Lambda $ of 6.9 to 9.0 TeV in the $ \mathrm{b}\mathrm{b}\ell\ell $ model, depending on model parameters, and on the ratio of energy scale and effective coupling, $ \Lambda/g_{*} $, of 2.0 to 2.6 TeV in the $ \mathrm{b}\mathrm{s}\ell\ell $ model. The latter represent the most stringent limits on this model to date. Lepton flavor universality is also tested by comparing the dielectron and dimuon mass spectra for different b-tagged jet multiplicities. No significant deviation from the standard model expectation of unity is observed. | ||
| Links: e-print arXiv:2506.13565 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; CADI line (restricted) ; | ||
| Figures | |
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Figure 1:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b}\mathrm{b}\ell\ell $ operator at the LHC, in association with 0 (left), 1 (center), and 2 (right) final state b quarks. |
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Figure 1-a:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b}\mathrm{b}\ell\ell $ operator at the LHC, in association with 0 (left), 1 (center), and 2 (right) final state b quarks. |
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Figure 1-b:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b}\mathrm{b}\ell\ell $ operator at the LHC, in association with 0 (left), 1 (center), and 2 (right) final state b quarks. |
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Figure 1-c:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b}\mathrm{b}\ell\ell $ operator at the LHC, in association with 0 (left), 1 (center), and 2 (right) final state b quarks. |
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Figure 2:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b} \mathrm{s}\ell\ell $ operator at the LHC, in association with 0 (left) and 1 (right) final state b quarks. |
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Figure 2-a:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b} \mathrm{s}\ell\ell $ operator at the LHC, in association with 0 (left) and 1 (right) final state b quarks. |
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Figure 2-b:
Representative Feynman diagrams for the production of dileptons via the $ \mathrm{b} \mathrm{s}\ell\ell $ operator at the LHC, in association with 0 (left) and 1 (right) final state b quarks. |
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Figure 3:
Observed data and various SM backgrounds in bins of DNN score evaluated from per-year and per-pseudorapidity trained models in the dielectron (left) and dimuon (right) channels. The solid cyan line in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectation for $ \Lambda = $ 6 TeV in the LL constructive interference model. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 3-a:
Observed data and various SM backgrounds in bins of DNN score evaluated from per-year and per-pseudorapidity trained models in the dielectron (left) and dimuon (right) channels. The solid cyan line in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectation for $ \Lambda = $ 6 TeV in the LL constructive interference model. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 3-b:
Observed data and various SM backgrounds in bins of DNN score evaluated from per-year and per-pseudorapidity trained models in the dielectron (left) and dimuon (right) channels. The solid cyan line in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectation for $ \Lambda = $ 6 TeV in the LL constructive interference model. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 4:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ CR as a function of $ m_{\mathrm{e}\mu} $ for the 0b (upper) and $ \geq $ 1b (lower) channels in the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields before correction with $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ values. |
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Figure 4-a:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ CR as a function of $ m_{\mathrm{e}\mu} $ for the 0b (upper) and $ \geq $ 1b (lower) channels in the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields before correction with $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ values. |
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Figure 4-b:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ CR as a function of $ m_{\mathrm{e}\mu} $ for the 0b (upper) and $ \geq $ 1b (lower) channels in the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields before correction with $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ values. |
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Figure 4-c:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ CR as a function of $ m_{\mathrm{e}\mu} $ for the 0b (upper) and $ \geq $ 1b (lower) channels in the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields before correction with $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ values. |
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Figure 4-d:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ CR as a function of $ m_{\mathrm{e}\mu} $ for the 0b (upper) and $ \geq $ 1b (lower) channels in the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields before correction with $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ values. |
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Figure 5:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ VR as a function of $ m_{\mathrm{e}\mu} $ for the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 5-a:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ VR as a function of $ m_{\mathrm{e}\mu} $ for the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 5-b:
Comparison of data and various SM backgrounds in the $ \mathrm{t} \overline{\mathrm{t}} $ VR as a function of $ m_{\mathrm{e}\mu} $ for the BB (left) and BE (right) categories. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 6:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mathrm{e}\mathrm{e} $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 6-a:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mathrm{e}\mathrm{e} $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 6-b:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mathrm{e}\mathrm{e} $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 7:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mu\mu $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 7-a:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mu\mu $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 7-b:
Ratio of simulated $ \mathrm{e}\mu $ events with SR selections and simulated $ \mu\mu $ events in the SR for the BB (left) and BE (right) categories. |
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Figure 8:
Comparison between data and various SM processes in DY+jets CR as a function of the number of b jets in the dielectron (left) and dimuon (right) channels. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 8-a:
Comparison between data and various SM processes in DY+jets CR as a function of the number of b jets in the dielectron (left) and dimuon (right) channels. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 8-b:
Comparison between data and various SM processes in DY+jets CR as a function of the number of b jets in the dielectron (left) and dimuon (right) channels. The lower panel of each plot shows the ratio of data to predicted background yields. |
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Figure 9:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+0b (left) and $ \mu\mu $+0b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 9-a:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+0b (left) and $ \mu\mu $+0b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 9-b:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+0b (left) and $ \mu\mu $+0b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 10:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+1b (left) and $ \mu\mu $+1b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 10-a:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+1b (left) and $ \mu\mu $+1b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 10-b:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+1b (left) and $ \mu\mu $+1b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panels correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 11:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+2b (left) and $ \mu\mu $+2b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panel correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 11-a:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+2b (left) and $ \mu\mu $+2b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panel correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 11-b:
Observed $ m_{\ell\ell} $ distributions in the data, and the post-fit backgrounds (stacked histograms), in the SR for $ \mathrm{e}\mathrm{e} $+2b (left) and $ \mu\mu $+2b (right) channels. The lower panels show ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The dashed band in the lower panels indicates the systematic component of the post-fit uncertainty. The solid lines in the upper panel correspond to the $ \mathrm{b}\mathrm{b}\ell\ell $ signal expectations, for $ \Lambda = $ 6 and 18 TeV in the LL constructive interference model. |
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Figure 12:
Ratio of the differential dilepton production cross section in the dimuon and dielectron channels as a function of dilepton mass in the 0b (left) and $ \geq $1b (right) final states. The ratio is obtained after correcting the dimuon and dielectron reconstructed mass spectra for bin-by-bin migration effects due to mass scale and resolution. The upper panel shows the observed flavor ratio in data and the DY+jets simulation. The lower panel shows the flavor ratio observed in data and in DY+jets simulation after correcting for the residual differences in acceptance and efficiency as a function of mass. The error bars include both statistical and systematic uncertainties. The shaded band represents the systematic uncertainties in the estimation. |
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Figure 12-a:
Ratio of the differential dilepton production cross section in the dimuon and dielectron channels as a function of dilepton mass in the 0b (left) and $ \geq $1b (right) final states. The ratio is obtained after correcting the dimuon and dielectron reconstructed mass spectra for bin-by-bin migration effects due to mass scale and resolution. The upper panel shows the observed flavor ratio in data and the DY+jets simulation. The lower panel shows the flavor ratio observed in data and in DY+jets simulation after correcting for the residual differences in acceptance and efficiency as a function of mass. The error bars include both statistical and systematic uncertainties. The shaded band represents the systematic uncertainties in the estimation. |
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Figure 12-b:
Ratio of the differential dilepton production cross section in the dimuon and dielectron channels as a function of dilepton mass in the 0b (left) and $ \geq $1b (right) final states. The ratio is obtained after correcting the dimuon and dielectron reconstructed mass spectra for bin-by-bin migration effects due to mass scale and resolution. The upper panel shows the observed flavor ratio in data and the DY+jets simulation. The lower panel shows the flavor ratio observed in data and in DY+jets simulation after correcting for the residual differences in acceptance and efficiency as a function of mass. The error bars include both statistical and systematic uncertainties. The shaded band represents the systematic uncertainties in the estimation. |
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Figure 13:
The 95% CL expected and observed lower limits on the energy scale $ \Lambda $ for the $ \mathrm{b}\mathrm{b}\ell\ell $ model with different chirality and interference assumptions, namely constructive left-left (ConLL), left-right (ConLR), right-left (ConRL), right-right (ConRR), destructive left-left (DesLL), left-right (DesLR), right-left (DesRL), and right-right (DesRR) in the $ \mathrm{e}\mathrm{e} $ (upper left), $ \mu\mu $ (upper right) channels, and the combination (lower) with $ \geq $0 b-tagged jets. |
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Figure 13-a:
The 95% CL expected and observed lower limits on the energy scale $ \Lambda $ for the $ \mathrm{b}\mathrm{b}\ell\ell $ model with different chirality and interference assumptions, namely constructive left-left (ConLL), left-right (ConLR), right-left (ConRL), right-right (ConRR), destructive left-left (DesLL), left-right (DesLR), right-left (DesRL), and right-right (DesRR) in the $ \mathrm{e}\mathrm{e} $ (upper left), $ \mu\mu $ (upper right) channels, and the combination (lower) with $ \geq $0 b-tagged jets. |
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Figure 13-b:
The 95% CL expected and observed lower limits on the energy scale $ \Lambda $ for the $ \mathrm{b}\mathrm{b}\ell\ell $ model with different chirality and interference assumptions, namely constructive left-left (ConLL), left-right (ConLR), right-left (ConRL), right-right (ConRR), destructive left-left (DesLL), left-right (DesLR), right-left (DesRL), and right-right (DesRR) in the $ \mathrm{e}\mathrm{e} $ (upper left), $ \mu\mu $ (upper right) channels, and the combination (lower) with $ \geq $0 b-tagged jets. |
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Figure 13-c:
The 95% CL expected and observed lower limits on the energy scale $ \Lambda $ for the $ \mathrm{b}\mathrm{b}\ell\ell $ model with different chirality and interference assumptions, namely constructive left-left (ConLL), left-right (ConLR), right-left (ConRL), right-right (ConRR), destructive left-left (DesLL), left-right (DesLR), right-left (DesRL), and right-right (DesRR) in the $ \mathrm{e}\mathrm{e} $ (upper left), $ \mu\mu $ (upper right) channels, and the combination (lower) with $ \geq $0 b-tagged jets. |
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Figure 14:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 0 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
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Figure 14-a:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 0 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
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Figure 14-b:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 0 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
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Figure 15:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 1 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
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Figure 15-a:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 1 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
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Figure 15-b:
Upper limits at 95% CL on the production cross section for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal in the $ \mathrm{e}\mathrm{e} $ (left) and $ \mu\mu $ (right) channels for 1 b-tagged jets. The shaded bands correspond to the 68 and 95% quantiles for the expected limits. The red line corresponds to the theoretical predictions for the $ \mathrm{b}\mathrm{s}\ell\ell $ signal [12]. |
| Tables | |
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Table 1:
Definitions of the SRs and CRs. |
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Table 2:
Measured values of the $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ in the OS $ \mathrm{t} \overline{\mathrm{t}} $ CR (BB category). |
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Table 3:
Measured values of the $ \text{SF}_{{\mathrm{t}\overline{\mathrm{t}}} } $ in the OS $ \mathrm{t} \overline{\mathrm{t}} $ CR (BE category). |
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Table 4:
Systematic uncertainties for the DY+jets background in the highest two mass bins for the $ \mathrm{e}\mathrm{e} $ channel. |
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Table 5:
Systematic uncertainties for the DY+jets background in the highest two mass bins for the $ \mu\mu $ channel. |
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Table 6:
Event yields for $ \mathrm{e}\mathrm{e} $ and $ \mu\mu $ channels in the 0b final state. The uncertainties include both statistical and systematic contributions. |
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Table 7:
Event yields for $ \mathrm{e}\mathrm{e} $ and $ \mu\mu $ channels in the 1b final state. The uncertainties include both statistical and systematic contributions. |
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Table 8:
Event yields for $ \mathrm{e}\mathrm{e} $ and $ \mu\mu $ channels in the 2b final state. The uncertainties include both statistical and systematic contributions. |
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Table 9:
Lower limits at 95% CL on the energy scale $ \Lambda $ in the $ \mathrm{b}\mathrm{b}\ell\ell $ signal model in TeVns for constructive left-left (ConLL), left-right (ConLR), right-left (ConRL), right-right (ConRR), destructive left-left (DesLL), left-right (DesLR), right-left (DesRL), and right-right (DesRR) chirality and interference assumptions in the dielectron and dimuon channels and the combination of the two. |
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Table 10:
Lower limits at 95% CL on $ \Lambda/g_{*} $ in the $ \mathrm{b}\mathrm{s}\ell\ell $ signal model in TeVns for 0b, 1b, and combined (0b+ 1b) channels. Shown are the expected and observed limits in the dielectron and dimuon channels and the combination of the two. |
| Summary |
| A search for new physics in the high-mass dilepton final state produced in association with b-tagged jets, focusing on nonresonant phenomena, has been performed using the proton-proton collision data collected during 2016-2018, corresponding to an integrated luminosity of 138 fb$ ^{-1} $. Two models of nonresonant signatures have been considered. For a four-fermion contact interaction in $ \mathrm{b}\mathrm{b}\ell\ell $ ($ \ell\ell $, electrons or muons) production, lower limits on the scale of new physics ($ \Lambda $) are set depending on the chirality structure of the interaction and the sign of its interference with the standard model Drell-Yan background. The observed limits are in the range from 6.9 to 9.0 TeV for the $ \mathrm{b}\mathrm{b}\ell\ell $ signal based on different chirality and interference assumptions. In the $ \mathrm{b}\mathrm{s}\ell\ell $ model, lower limits on the ratio of the energy scale of new physics to the coupling ($ \Lambda/g_{*} $) range from 1.9 to 2.2 TeV depending on the channel and 2.4 TeV for the combination of all the channels. The limits on the $ \mathrm{b}\mathrm{s}\ell\ell $ model are the most stringent to date. Additionally, the dielectron and dimuon invariant mass spectra are compared at the TeVns scale. No significant deviation in the lepton flavor ratio from the standard model expectation is observed. |
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