Search for pair production of higgsinos in events with two Higgs bosons and missing transverse momentum in $\sqrt{s}=13$ TeV $pp$ collisions at the ATLAS experiment

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
Phys.Rev.D 109 (2024) 112011, 2024.
Inspire Record 2751932 DOI 10.17182/hepdata.136030

This paper presents a search for pair production of higgsinos, the supersymmetric partners of the Higgs bosons, in scenarios with gauge-mediated supersymmetry breaking. Each higgsino is assumed to decay into a Higgs boson and a nearly massless gravitino. The search targets events where each Higgs boson decays into $b\bar{b}$, leading to a reconstructed final state with at least three energetic $b$-jets and This paper presents a search for pair production of higgsinos, the supersymmetric partners of the Higgs bosons, in scenarios with gauge-mediated supersymmetry breaking. Each higgsino is assumed to decay into a Higgs boson and a nearly massless gravitino. The search targets events where each Higgs boson decays into $b\bar{b}$, leading to a reconstructed final state with at least three energetic $b$-jets and missing transverse momentum. Two complementary analysis channels are used, with each channel specifically targeting either low or high values of the higgsino mass. The low-mass (high-mass) channel exploits 126 (139) fb$^{-1}$ of $\sqrt{s}=13$ TeV data collected by the ATLAS detector during Run 2 of the Large Hadron Collider. No significant excess above the Standard Model prediction is found. At 95% confidence level, masses between 130 GeV and 940 GeV are excluded for higgsinos decaying exclusively into Higgs bosons and gravitinos. Exclusion limits as a function of the higgsino decay branching ratio to a Higgs boson are also reported.

66 data tables

Post-fit SR yields of the high-mass channel. The upper panel shows the observed number of events, as well the post-fit background predictions in each region. The bottom panel shows the ratio of the observed data and the total background prediction. The shaded areas correspond to the total statistical and systematic uncertainties obtained after the fit and described in Section 6.

Post-fit SR yields of the high-mass channel. The upper panel shows the observed number of events, as well the post-fit background predictions in each region. The bottom panel shows the ratio of the observed data and the total background prediction. The shaded areas correspond to the total statistical and systematic uncertainties obtained after the fit and described in Section 6.

Post-fit SR yields of the high-mass channel. The upper panel shows the observed number of events, as well the post-fit background predictions in each region. The bottom panel shows the ratio of the observed data and the total background prediction. The shaded areas correspond to the total statistical and systematic uncertainties obtained after the fit and described in Section 6.

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Measurement of simplified template cross sections of the Higgs boson produced in association with W or Z bosons in the H $\to$$\mathrm{b\bar{b}}$ decay channel in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.D 109 (2024) 092011, 2024.
Inspire Record 2736546 DOI 10.17182/hepdata.145636

Differential cross sections are measured for the standard model Higgs boson produced in association with vector bosons (W, Z) and decaying to a pair of b quarks. Measurements are performed within the framework of the simplified template cross sections. The analysis relies on the leptonic decays of the W and Z bosons, resulting in final states with 0, 1, or 2 electrons or muons. The Higgs boson candidates are either reconstructed from pairs of resolved b-tagged jets, or from single large distance parameter jets containing the particles arising from two b quarks. Proton-proton collision data at $\sqrt{s}$ = 13 TeV, collected by the CMS experiment in 2016-2018 and corresponding to a total integrated luminosity of 138 fb$^{-1}$, are analyzed. The inclusive signal strength, defined as the product of the observed production cross section and branching fraction relative to the standard model expectation, combining all analysis categories, is found to be $\mu$ = 1.15 $^{+0.22}_{-0.20}$. This corresponds to an observed (expected) significance of 6.3 (5.6) standard deviations.

3 data tables

Measured product of cross section and branching fraction as well as signal strength, defined as the ratio of the observed signal cross section to the Standard Model expectation, in the V(leptonic)H STXS process scheme from the analysis of the 2016, 2017 and 2018 data. If the observed signal strength for a given STXS bin is negative, no uncertainty is reported for the associated bin.

Signal strength per signal process. All results combine the 2016, 2017 and 2018 data-taking years.

Signal strength per analysis channels. All results combine the 2016, 2017 and 2018 data-taking years.


Search for short- and long-lived axion-like particles in $H\rightarrow a a \rightarrow 4\gamma$ decays with the ATLAS experiment at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
Eur.Phys.J.C 84 (2024) 742, 2024.
Inspire Record 2731621 DOI 10.17182/hepdata.144534

Presented is the search for anomalous Higgs boson decays into two axion-like particles (ALPs) using the full Run 2 data set of 140 fb$^{-1}$ of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS experiment. The ALPs are assumed to decay into two photons, providing sensitivity to recently proposed models that could explain the $(g-2)_\mu$ discrepancy. This analysis covers an ALP mass range from 100 MeV to 62 GeV and ALP-photon couplings in the range $10^{-5}\, \text{TeV}^{-1}<C_{a\gamma\gamma}/\Lambda<1\, \text{TeV}^{-1}$, and therefore includes signatures with significantly displaced vertices and highly collinear photons. No significant excess of events above the Standard Model background is observed. Upper limits at 95% confidence level are placed on the branching ratio of the Higgs boson to two ALPs in the four-photon final state, and are in the range of $ 10^{-5}$ to $3\times 10^{-2}$, depending on the hypothesized ALP mass and ALP-photon coupling strength.

11 data tables

Cut-flow and number of events in a region with $110 \text{ GeV} <m_{aa}<130 \text{ GeV}$ for selected signal samples

Overview of relative systematic uncertainties on the signal normalization for selected couplings and mass points in the dominant categories. All photon related uncertainties are summarized under "standard photon", while all customised photon related uncertainties (e.g. displaced photons, NN-based photon IDs) are summarized under "custom photon".

Upper limits on $\mathcal{B}(H\rightarrow aa\rightarrow 4\gamma)$ at 95% CL as a function of the axion mass and for ALP-photon coupling $C_{a\gamma\gamma}=1$.

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Search for dark matter produced in association with a Higgs boson decaying to tau leptons at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 09 (2023) 189, 2023.
Inspire Record 2661503 DOI 10.17182/hepdata.140433

A search for dark matter produced in association with a Higgs boson in final states with two hadronically decaying $\tau$-leptons and missing transverse momentum is presented. The analysis uses $139$ fb$^{-1}$ of proton-proton collision data at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider between 2015 and 2018. No evidence for physics beyond the Standard Model is found. The results are interpreted in terms of a 2HDM+$a$ model. Exclusion limits at 95% confidence level are derived. Model-independent limits are also set on the visible cross section for processes beyond the Standard Model producing missing transverse momentum in association with a Higgs boson decaying to $\tau$-leptons.

70 data tables

<b>- - - - - - - - Overview of HEPData Record - - - - - - - -</b> <br><br> <b>CLs and CLs+b values</b> <ul> <li><a href=?table=CLs_tanb_mA_grid_Expected>Expected CLs values in mA vs tanB grid, Low mA SR</a> <li><a href=?table=CLs_tanb_mA_grid_Observed>Observed CLs values in mA vs tanB grid, Low mA SR</a> <li><a href=?table=CLs_ma_mA_grid_HighmA_SR_Expected>Expected CLs values in mA vs ma grid, High mA SR</a> <li><a href=?table=CLs_ma_mA_grid_HighmA_SR_Observed>Observed CLs values in mA vs ma grid, High mA SR</a> <li><a href=?table=CLs_ma_mA_grid_LowmA_SR_Expected>Expected CLs values in mA vs ma grid, Low mA SR</a> <li><a href=?table=CLs_ma_mA_grid_LowmA_SR_Observed>Observed CLs values in mA vs ma grid, Low mA SR</a> <li><a href=?table=CLsplusb_tanb_mA_grid>CLs+b values in mA vs tanB grid, Low mA SR</a> <li><a href=?table=CLsplusb_ma_mA_grid_HighmA_SR>CLs+b values in mA vs ma grid, High mA SR</a> <li><a href=?table=CLsplusb_ma_mA_grid_LowmA_SR>CLs+b values in mA vs ma grid, Low mA SR</a> </ul> <b>Cutflow tables</b> <ul> <li><a href=?table=Cutflows_ggf_LowmA_SR>Low mA SR, ggF production</a> <li><a href=?table=Cutflows_ggf_HighmA_SR>High mA SR, ggF production</a> <li><a href=?table=Cutflows_bb_LowmA_SR>Low mA SR, bb production</a> <li><a href=?table=Cutflows_bb_HighmA_SR>High mA SR, bb production</a> </ul> <b>Kinematic Distributions</b> <ul> <li><a href=?table=KinDist_LowmA_SR>Low mA SR mTtau1+mTtau2 distribution</a> <li><a href=?table=KinDist_HighmA_SR>High mA SR mTtau1+mTtau2 distribution</a> </ul> <b>Limits</b> <ul> <li><a href=?table=Expected_95%_CL_exclusion_limit_mAma_grid>Expected 95% CL exclusion limit in mA vs ma grid</a> <li><a href=?table=Observed_95%_CL_exclusion_limit_mAma_grid>Observed 95% CL exclusion limit in mA vs ma grid</a> <li><a href=?table=Expected_pm1sigma_95%_CL_exclusion_limit_mAma_grid>Expected +-1 sigma 95% CL exclusion limit in mA vs ma grid</a> <li><a href=?table=Expected_95%_CL_exclusion_limit_mAtanB_grid>Expected 95% CL exclusion limit in mA vs tanB grid</a> <li><a href=?table=Observed_95%_CL_exclusion_limit_mAtanB_grid>Observed 95% CL exclusion limit in mA vs tanB grid</a> <li><a href=?table=Expected_pm1sigma_95%_CL_exclusion_limit_mAtanB_grid>Expected +-1 sigma 95% CL exclusion limit in tanB grid</a> </ul> <b>Acceptance and efficiency</b> <ul> <li><a href=?table=table1>Acceptance, High mA SR, mA vs tanB grid, 400-750 GeV, bb prod</a> <li><a href=?table=table2>Acceptance, High mA SR, mA vs tanB grid, >750 GeV, bb prod</a> <li><a href=?table=table3>Acceptance, Low mA SR, mA vs tanB grid, 100-250 GeV, bb prod</a> <li><a href=?table=table4>Acceptance, Low mA SR, mA vs tanB grid, 250-400 GeV, bb prod</a> <li><a href=?table=table5>Acceptance, Low mA SR, mA vs tanB grid, 400-550 GeV, bb prod</a> <li><a href=?table=table6>Acceptance, Low mA SR, mA vs tanB grid, >550 GeV, bb prod</a> <li><a href=?table=table7>Acceptance, High mA SR, mA vs ma grid, 400-750 GeV, bb prod</a> <li><a href=?table=table8>Acceptance, High mA SR, mA vs ma grid, >750 GeV, bb prod</a> <li><a href=?table=table9>Acceptance, Low mA SR, mA vs ma grid, 100-250 GeV, bb prod</a> <li><a href=?table=table10>Acceptance, Low mA SR, mA vs ma grid, 250-400 GeV, bb prod</a> <li><a href=?table=table11>Acceptance, Low mA SR, mA vs ma grid, 400-550 GeV, bb prod</a> <li><a href=?table=table12>Acceptance, Low mA SR, mA vs ma grid, >550 GeV, bb prod</a> <li><a href=?table=table13>Acceptance, High mA SR, mA vs tanB grid, 400-750 GeV, ggF prod</a> <li><a href=?table=table14>Acceptance, High mA SR, mA vs tanB grid, >750 GeV, ggF prod</a> <li><a href=?table=table15>Acceptance, Low mA SR, mA vs tanB grid, 100-250 GeV, ggF prod</a> <li><a href=?table=table16>Acceptance, Low mA SR, mA vs tanB grid, 250-400 GeV, ggF prod</a> <li><a href=?table=table17>Acceptance, Low mA SR, mA vs tanB grid, 400-550 GeV, ggF prod</a> <li><a href=?table=table18>Acceptance, Low mA SR, mA vs tanB grid, >550 GeV, ggF prod</a> <li><a href=?table=table19>Acceptance, High mA SR, mA vs ma grid, 400-750 GeV, ggF prod</a> <li><a href=?table=table20>Acceptance, High mA SR, mA vs ma grid, >750 GeV, ggF prod</a> <li><a href=?table=table21>Acceptance, Low mA SR, mA vs ma grid, 100-250 GeV, ggF prod</a> <li><a href=?table=table22>Acceptance, Low mA SR, mA vs ma grid, 250-400 GeV, ggF prod</a> <li><a href=?table=table23>Acceptance, Low mA SR, mA vs ma grid, 400-550 GeV, ggF prod</a> <li><a href=?table=table24>Acceptance, Low mA SR, mA vs ma grid, >550 GeV, ggF prod</a> <li><a href=?table=table25>Efficiency, High mA SR, mA vs tanB grid, 400-750 GeV, bb prod</a> <li><a href=?table=table26>Efficiency, High mA SR, mA vs tanB grid, >750 GeV, bb prod</a> <li><a href=?table=table27>Efficiency, Low mA SR, mA vs tanB grid, 100-250 GeV, bb prod</a> <li><a href=?table=table28>Efficiency, Low mA SR, mA vs tanB grid, 250-400 GeV, bb prod</a> <li><a href=?table=table29>Efficiency, Low mA SR, mA vs tanB grid, 400-550 GeV, bb prod</a> <li><a href=?table=table30>Efficiency, Low mA SR, mA vs tanB grid, >550 GeV, bb prod</a> <li><a href=?table=table31>Efficiency, High mA SR, mA vs ma grid, 400-750 GeV, bb prod</a> <li><a href=?table=table32>Efficiency, High mA SR, mA vs ma grid, >750 GeV, bb prod</a> <li><a href=?table=table33>Efficiency, Low mA SR, mA vs ma grid, 100-250 GeV, bb prod</a> <li><a href=?table=table34>Efficiency, Low mA SR, mA vs ma grid, 250-400 GeV, bb prod</a> <li><a href=?table=table35>Efficiency, Low mA SR, mA vs ma grid, 400-550 GeV, bb prod</a> <li><a href=?table=table36>Efficiency, Low mA SR, mA vs ma grid, >550 GeV, bb prod</a> <li><a href=?table=table37>Efficiency, High mA SR, mA vs tanB grid, 400-750 GeV, ggF prod</a> <li><a href=?table=table38>Efficiency, High mA SR, mA vs tanB grid, >750 GeV, ggF prod</a> <li><a href=?table=table39>Efficiency, Low mA SR, mA vs tanB grid, 100-250 GeV, ggF prod</a> <li><a href=?table=table40>Efficiency, Low mA SR, mA vs tanB grid, 250-400 GeV, ggF prod</a> <li><a href=?table=table41>Efficiency, Low mA SR, mA vs tanB grid, 400-550 GeV, ggF prod</a> <li><a href=?table=table42>Efficiency, Low mA SR, mA vs tanB grid, >550 GeV, ggF prod</a> <li><a href=?table=table43>Efficiency, High mA SR, mA vs ma grid, 400-750 GeV, ggF prod</a> <li><a href=?table=table44>Efficiency, High mA SR, mA vs ma grid, >750 GeV, ggF prod</a> <li><a href=?table=table45>Efficiency, Low mA SR, mA vs ma grid, 100-250 GeV, ggF prod</a> <li><a href=?table=table46>Efficiency, Low mA SR, mA vs ma grid, 250-400 GeV, ggF prod</a> <li><a href=?table=table47>Efficiency, Low mA SR, mA vs ma grid, 400-550 GeV, ggF prod</a> <li><a href=?table=table48>Efficiency, Low mA SR, mA vs ma grid, >550 GeV, ggF prod</a> </ul>

Expected CLs values in the Low mA SR, mA vs tanB signal grid.

Observed CLs values in the Low mA SR, mA vs tanB signal grid.

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Version 2
Searches for lepton-flavour-violating decays of the Higgs boson into $e\tau$ and $\mu\tau$ in $\sqrt{s}=13$ TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
JHEP 07 (2023) 166, 2023.
Inspire Record 2631088 DOI 10.17182/hepdata.135719

This paper presents direct searches for lepton flavour violation in Higgs boson decays, $H\rightarrow e\tau$ and $H\rightarrow\mu\tau$, performed using data collected with the ATLAS detector at the LHC. The searches are based on a data sample of proton-proton collisions at a centre-of-mass energy $\sqrt{s} = 13$ TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. Leptonic ($\tau \rightarrow \ell \nu_\ell \nu_\tau$) and hadronic ($\tau \rightarrow $ hadrons $ \nu_\tau$) decays of the $\tau$-lepton are considered. Two background estimation techniques are employed: the MC-template method, based on data-corrected simulation samples, and the Symmetry method, based on exploiting the symmetry between electrons and muons in the Standard Model backgrounds. No significant excess of events is observed and the results are interpreted as upper limits on lepton-flavour-violating branching ratios of the Higgs boson. The observed (expected) upper limits set on the branching ratios at 95% confidence level, $\mathcal{B}(H\rightarrow e\tau)<0.20\%$ (0.12%) and $\mathcal{B}(H\rightarrow \mu\tau)<0.18\%$ (0.09%), are obtained with the MC-template method from a simultaneous measurement of potential $H \rightarrow e\tau$ and $H \rightarrow\mu\tau$ signals. The best-fit branching ratio difference, $\mathcal{B}(H\rightarrow \mu\tau)- \mathcal{B}(H\rightarrow e\tau)$, measured with the Symmetry method in the channel where the $\tau$-lepton decays to leptons, is (0.25 $\pm$ 0.10)%, compatible with a value of zero within 2.5$\sigma$.

20 data tables

Fit results of the simultaneous measurements of the $H\to e\tau$ and $H\to \mu\tau$ signals (2POI) showing upper limits at 95% C.L. on the LFV branching ratios of the Higgs boson $H\to e\tau$. The results from standalone channel/categories fits are compared with the results of the combined fit.

Fit results of the simultaneous measurements of the $H\to e\tau$ and $H\to \mu\tau$ signals (2POI) showing best-fit values of the LFV branching ratios of the Higgs boson $\hat{B}$($H\to e\tau$). The results from standalone channel/categories fits are compared with the results of the combined fit.

Fit results of the simultaneous measurements of the $H\to e\tau$ and $H\to \mu\tau$ signals (2POI) showing upper limits at 95% C.L. on the LFV branching ratios of the Higgs boson $H\to \mu\tau$. The results from standalone channel/categories fits are compared with the results of the combined fit.

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Measurement of the $CP$ properties of Higgs boson interactions with $\tau$-leptons with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Eur.Phys.J.C 83 (2023) 563, 2023.
Inspire Record 2613280 DOI 10.17182/hepdata.131601

A study of the charge conjugation and parity ($CP$) properties of the interaction between the Higgs boson and $\tau$-leptons is presented. The study is based on a measurement of $CP$-sensitive angular observables defined by the visible decay products of $\tau$-lepton decays, where at least one hadronic decay is required. The analysis uses 139 fb$^{-1}$ of proton$-$proton collision data recorded at a centre-of-mass energy of $\sqrt{s}= 13$ TeV with the ATLAS detector at the Large Hadron Collider. Contributions from $CP$-violating interactions between the Higgs boson and $\tau$-leptons are described by a single mixing angle parameter $\phi_{\tau}$ in the generalised Yukawa interaction. Without assuming the Standard Model hypothesis for the $H\rightarrow\tau\tau$ signal strength, the mixing angle $\phi_{\tau}$ is measured to be $9^{\circ} \pm 16^{\circ}$, with an expected value of $0^{\circ} \pm 28^{\circ}$ at the 68% confidence level. The pure $CP$-odd hypothesis is disfavoured at a level of 3.4 standard deviations. The results are compatible with the predictions for the Higgs boson in the Standard Model.

5 data tables

Observed 1-D likelihood scan of the $CP$-mixing angle $\phi_{\tau}$.

Expected 1-D likelihood scan of the $CP$-mixing angle $\phi_{\tau}$.

Observed 2-D likelihood scan of the signal strength $\mu_{\tau\tau}$ versus the $CP$-mixing angle $\phi_{\tau}$.

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Search for new physics using effective field theory in 13 TeV pp collision events that contain a top quark pair and a boosted Z or Higgs boson

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.D 108 (2023) 032008, 2023.
Inspire Record 2142913 DOI 10.17182/hepdata.127700

A data sample containing top quark pairs ($\mathrm{t\bar{t}}$) produced in association with a Lorentz-boosted Z or Higgs boson is used to search for signs of new physics using effective field theory. The data correspond to an integrated luminosity of 138 fb$^{-1}$ of proton-proton collisions produced at a center-of-mass energy of 13 TeV at the LHC and collected by the CMS experiment. Selected events contain a single lepton and hadronic jets, including two identified with the decay of bottom quarks, plus an additional large-radius jet with high transverse momentum identified as a Z or Higgs boson decaying to a bottom quark pair. Machine learning techniques are employed to discriminate between $\mathrm{t\bar{t}}$Z or $\mathrm{t\bar{t}}$H events and events from background processes, which are dominated by $\mathrm{t\bar{t}}$ + jets production. No indications of new physics are observed. The signal strengths of boosted $\mathrm{t\bar{t}}$Z and $\mathrm{t\bar{t}}$H production are measured, and upper limits are placed on the $\mathrm{t\bar{t}}$Z and $\mathrm{t\bar{t}}$H differential cross sections as functions of the Z or Higgs boson transverse momentum. The effects of new physics are probed using a framework in which the standard model is considered to be the low-energy effective field theory of a higher energy scale theory. Eight possible dimension-six operators are added to the standard model Lagrangian and their corresponding coefficients are constrained via fits to the data.

20 data tables

Negative log-likelihood difference in $\mu_{\text{ttH}}, \mu_{\text{ttZ}}$ for a Z or Higgs boson with a simulated pT $> 200$GeV

Negative log-likelihood difference in $\text{c}_{\text{t}\varphi}$ where the other Wilson coefficients are fixed to 0.

Negative log-likelihood difference in $\text{c}_{\varphi\text{Q}}^{-}$ where the other Wilson coefficients are fixed to 0.

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Search for flavour-changing neutral current interactions of the top quark and the Higgs boson in events with a pair of $\tau$-leptons in pp collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
JHEP 2306 (2023) 155, 2023.
Inspire Record 2141572 DOI 10.17182/hepdata.130958

A search for flavour-changing neutral current (FCNC) $tqH$ interactions involving a top quark, another up-type quark ($q=u$, $c$), and a Standard Model (SM) Higgs boson decaying into a $\tau$-lepton pair ($H\rightarrow \tau^+\tau^-$) is presented. The search is based on a dataset of $pp$ collisions at $\sqrt{s}=13$ TeV that corresponds to an integrated luminosity of 139 fb$^{-1}$ recorded with the ATLAS detector at the Large Hadron Collider. Two processes are considered: single top quark FCNC production in association with a Higgs boson ($pp\rightarrow tH$), and top quark pair production in which one of the top quarks decays into $Wb$ and the other decays into $qH$ through the FCNC interactions. The search selects events with two hadronically decaying $\tau$-lepton candidates ($\tau_{\text{had}}$) or at least one $\tau_{\text{had}}$ with an additional lepton ($e$, $\mu$), as well as multiple jets. Event kinematics is used to separate signal from the background through a multivariate discriminant. A slight excess of data is observed with a significance of 2.3$\sigma$ above the expected SM background, and 95% CL upper limits on the $t\to qH$ branching ratios are derived. The observed (expected) 95% CL upper limits set on the $t\to cH$ and $t\to uH$ branching ratios are $9.4 \times 10^{-4}$ $(4.8^{+2.2}_{-1.4}\times 10^{-4})$ and $6.9\times 10^{-4}$ $(3.5^{+1.5}_{-1.0}\times 10^{-4})$, respectively. The corresponding combined observed (expected) upper limits on the dimension-6 operator Wilson coefficients in the effective $tqH$ couplings are $C_{c\phi} <1.35$ $(0.97)$ and $C_{u\phi} <1.16$ $(0.82)$.

54 data tables

Leading tau Pt distributions obtained before the fit to data (Pre-Fit) showing the expected background and tuH signals after applying fake factors in the $t_{\ell}\tau_{had}\tau_{had}$ region. Other MC includes single top, V+jets, and other small backgrounds. The tuH signals with nominal branching ratio of 0.1% are scaled using normalization factors of 2 to 50. Statistical and systematic uncertainties are included in the "Total background".

Leading tau Pt distributions obtained before the fit to data (Pre-Fit) showing the expected background and tuH signals after applying fake factors in the $t_{\ell}\tau_{had}$-1j region. Other MC includes single top, V+jets, and other small backgrounds. The tuH signals with nominal branching ratio of 0.1% are scaled using normalization factors of 2 to 50. Statistical and systematic uncertainties are included in the "Total background".

Leading tau Pt distributions obtained before the fit to data (Pre-Fit) showing the expected background and tuH signals after applying fake factors in the $t_{\ell}\tau_{had}$-2j region. Other MC includes single top, V+jets, and other small backgrounds. The tuH signals with nominal branching ratio of 0.1% are scaled using normalization factors of 2 to 50. Statistical and systematic uncertainties are included in the "Total background".

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Version 2
Searches for exclusive Higgs and $Z$ boson decays into a vector quarkonium state and a photon using $139$ fb$^{-1}$ of ATLAS $\sqrt{s}=13$ TeV proton$-$proton collision data

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, D.C. ; et al.
Eur.Phys.J.C 83 (2023) 781, 2023.
Inspire Record 2132750 DOI 10.17182/hepdata.132657

Searches for the exclusive decays of Higgs and $Z$ bosons into a vector quarkonium state and a photon are performed in the $\mu^+\mu^- \gamma$ final state with a proton$-$proton collision data sample corresponding to an integrated luminosity of $139$ fb$^{-1}$ collected at $\sqrt{s}=13$ TeV with the ATLAS detector at the CERN Large Hadron Collider. The observed data are compatible with the expected backgrounds. The 95% confidence-level upper limits on the branching fractions of the Higgs boson decays into $J/\psi \gamma$, $\psi(2S) \gamma$, and $\Upsilon(1S,2S,3S) \gamma$ are found to be $2.0\times10^{-4}$, $10.5\times10^{-4}$, and $(2.5,4.2,3.4)\times10^{-4}$, respectively, assuming Standard Model production of the Higgs boson. The corresponding 95% CL upper limits on the branching fractions of the $Z$ boson decays are $1.2\times10^{-6}$, $2.4\times10^{-6}$, and $(1.1,1.3,2.4)\times10^{-6}$. An observed 95% CL interval of $(-133,175)$ is obtained for the $\kappa_c/\kappa_\gamma$ ratio of Higgs boson coupling modifiers, and a 95% CL interval of $(-37,40)$ is obtained for $\kappa_b/\kappa_\gamma$.

2 data tables

Numbers of observed and expected background events for the $m_{\mu^+\mu^-\gamma}$ ranges of interest. Each expected background and the corresponding uncertainty of its mean is obtained from a background-only fit to the data; the uncertainty does not take into account statistical fluctuations in each mass range. Expected $Z$ and Higgs boson signal contributions, with their corresponding total systematic uncertainty, are shown for reference branching fractions of $10^{-6}$ and $10^{-3}$, respectively. The ranges in $m_{\mu^+\mu^-}$ are centred around each quarkonium resonance, with a width driven by the resolution of the detector; in particular, the ranges for the $\Upsilon(nS)$ resonances are based on the resolution in the endcaps. It is noted that the discrepancy between the observed and expected backgrounds for $m_{\mu^+\mu^-} = 9.0$-$9.8$ GeV in the endcaps was found to have a small impact on the observed limit for $Z\rightarrow\Upsilon(1S)\,\gamma$.

Expected, with the corresponding $\pm 1\sigma$ intervals, and observed 95% CL branching fraction upper limits for the Higgs and $Z$ boson decays into a quarkonium state and a photon. Standard Model production of the Higgs boson is assumed. The corresponding upper limits on the production cross section times branching fraction $\sigma\times\mathcal{B}$ are also shown.


Searches for additional Higgs bosons and for vector leptoquarks in $\tau\tau$ final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 07 (2023) 073, 2023.
Inspire Record 2132368 DOI 10.17182/hepdata.128147

Three searches are presented for signatures of physics beyond the standard model (SM) in $\tau\tau$ final states in proton-proton collisions at the LHC, using a data sample collected with the CMS detector at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. Upper limits at 95% confidence level (CL) are set on the products of the branching fraction for the decay into $\tau$ leptons and the cross sections for the production of a new boson $\phi$, in addition to the H(125) boson, via gluon fusion (gg$\phi$) or in association with b quarks, ranging from $\mathcal{O}$(10 pb) for a mass of 60 GeV to 0.3 fb for a mass of 3.5 TeV each. The data reveal two excesses for gg$\phi$ production with local $p$-values equivalent to about three standard deviations at $m_\phi$ = 0.1 and 1.2 TeV. In a search for $t$-channel exchange of a vector leptoquark U$_1$, 95% CL upper limits are set on the dimensionless U$_1$ leptoquark coupling to quarks and $\tau$ leptons ranging from 1 for a mass of 1 TeV to 6 for a mass of 5 TeV, depending on the scenario. In the interpretations of the $M_\mathrm{h}^{125}$ and $M_\mathrm{h, EFT}^{125}$ minimal supersymmetric SM benchmark scenarios, additional Higgs bosons with masses below 350 GeV are excluded at 95% CL.

313 data tables

Expected and observed $95\%\text{ CL}$ upper limits on the product of the cross sections and branching fraction for the decay into $\tau$ leptons for $gg\phi$ production in a mass range of $60\leq m_\phi\leq 3500\text{ GeV}$, in addition to $\text{H}(125)$. The central $68$ and $95\%$ intervals are given in addition to the expected median value. In this case, $bb\phi$ production rate has been profiled. The peak in the expected $gg\phi$ limit is tribute to a loss of sensitivity around $90\text{ GeV}$ due to the background from $Z/\gamma^\ast\rightarrow\tau\tau$ events. Numerical values provided in this table correspond to Figure 10a of the publication.

Expected and observed $95\%\text{ CL}$ upper limits on the product of the cross sections and branching fraction for the decay into $\tau$ leptons for $bb\phi$ production in a mass range of $60\leq m_\phi\leq 3500\text{ GeV}$, in addition to $\text{H}(125)$. The central $68$ and $95\%$ intervals are given in addition to the expected median value. In this case, $gg\phi$ production rate has been profiled. Numerical values provided in this table correspond to Figure 10b of the publication.

Expected and observed $95\%\text{ CL}$ upper limits on the product of the cross sections and branching fraction for the decay into $\tau$ leptons for $gg\phi$ production in a mass range of $60\leq m_\phi\leq 3500\text{ GeV}$, in addition to $\text{H}(125)$. The central $68$ and $95\%$ intervals are given in addition to the expected median value. In this case, $bb\phi$ production rate has been fixed to zero. Numerical values provided in this table correspond to Figure 37 of the auxilliary material of the publication.

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