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| CMS-PAS-EXO-22-018 | ||
| Search for leptoquarks produced in lepton-quark collisions and coupling to $ \tau $ leptons | ||
| CMS Collaboration | ||
| 22 May 2023 | ||
| Abstract: A search for leptoquarks produced in lepton-quark collisions and coupling to $ \tau $ leptons is presented. It is based on a data set of proton-proton collision events recorded by the CMS detector at the LHC at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 138 fb$ ^{-1} $. The reconstructed final state consists of a jet, significant missing transverse momentum, and a $ \tau $ lepton reconstructed through its leptonic or hadronic decays. Limits are set on the leptoquark production cross section times branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the coupling strength of the leptoquark-lepton-quark vertex. These results complement the constraints on the leptoquark-$ \tau $-b couplings set by previous searches in other production modes, while they are the first limits for leptoquark-$ \tau $-u, leptoquark-$ \tau $-d, and leptoquark-$ \tau $-s couplings. | ||
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Links:
CDS record (PDF) ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, Submitted to PRL. The superseded preliminary plots can be found here. |
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| Figures | |
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Figure 1:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
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Figure 1-a:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
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Figure 1-b:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
png pdf |
Figure 1-c:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
png pdf |
Figure 1-d:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
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Figure 1-e:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
png pdf |
Figure 1-f:
Observed and expected distributions of the collinear mass in the $ \tau_\mathrm{h}$+jet (left), $ \mathrm{e}$+jet (center), and $ \mu$+jet (right) channels for the btag (top) and no-btag (bottom) categories with the highest BDT output requirements. The uncertainty band includes statistical and systematic uncertainties, and the background distributions are the results of the maximum likelihood fit. |
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Figure 2:
Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupling to b quarks and $ \tau $ leptons (left), or to light-flavor quarks and $ \tau $ leptons (right), using $ \lambda= $ 1.5. |
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Figure 2-a:
Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupling to b quarks and $ \tau $ leptons (left), or to light-flavor quarks and $ \tau $ leptons (right), using $ \lambda= $ 1.5. |
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Figure 2-b:
Expected and observed upper limits at 95% CL on the scalar lepton-induced LQ production cross section times branching fraction for a LQ coupling to b quarks and $ \tau $ leptons (left), or to light-flavor quarks and $ \tau $ leptons (right), using $ \lambda= $ 1.5. |
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Figure 3:
Expected upper limit at 95% CL on the coupling strength $ \lambda $ of a scalar LQ to b quarks and $ \tau $ leptons (left), and to light-flavor quarks and $ \tau $ leptons (right). |
png pdf |
Figure 3-a:
Expected upper limit at 95% CL on the coupling strength $ \lambda $ of a scalar LQ to b quarks and $ \tau $ leptons (left), and to light-flavor quarks and $ \tau $ leptons (right). |
png pdf |
Figure 3-b:
Expected upper limit at 95% CL on the coupling strength $ \lambda $ of a scalar LQ to b quarks and $ \tau $ leptons (left), and to light-flavor quarks and $ \tau $ leptons (right). |
| Tables | |
png pdf |
Table 1:
Selection criteria, where $ \ell $ stands for $ \tau_\mathrm{h} $, $ \mu $, or e, depending on the final state. |
| Summary |
| As a summary, a search for leptoquarks produced via lepton-induced production and coupling to $ \tau $ leptons has been performed for the first time, using data collected by the CMS detector in Run-2. The limits are competitive with those set using other production modes at high mass and coupling values for $ \mathrm{b}\tau $ couplings, while limits on the couplings of leptoquarks to light-flavor quarks and $ \tau $ leptons are set for the first time. |
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