Date

Model-independent search for pair production of new bosons decaying into muons in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-HIG-21-004, 2024.
Inspire Record 2812281 DOI 10.17182/hepdata.150033

The results of a model-independent search for the pair production of new bosons within a mass range of 0.21 $\lt$$m$$\lt$ 60 GeV, are presented. This study utilizes events with a four-muon final state. We use two data sets, comprising 41.5 fb$^{-1}$ and 59.7 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV, recorded in 2017 and 2018 by the CMS experiment at the CERN LHC. The study of the 2018 data set includes a search for displaced signatures of a new boson within the proper decay length range of 0 $\lt$$c\tau$$\lt$ 100 $\mu$m. Our results are combined with a previous CMS result, based on 35.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV collected in 2016. No significant deviation from the expected background is observed. Results are presented in terms of a model-independent upper limit on the product of cross section, branching fraction, and acceptance. The findings are interpreted across various benchmark models, such as an axion-like particle model, a vector portal model, the next-to-minimal supersymmetric standard model, and a dark supersymmetric scenario, including those predicting a non-negligible proper decay length of the new boson. In all considered scenarios, substantial portions of the parameter space are excluded, expanding upon prior results.

11 data tables

The model-independent 95\% \CL expected and observed upper limits set on ${\sigma(\PP\to 2\Pa+\PX)\mathcal{B}^2(\Pa\to 2\PGm)\alphaGen}$ over the range $0.21 < \MPa < 60\GeV$ for the 2017 analysis. Mass ranges that overlap with \JPsi and \PgU resonances are excluded from the search

The model-independent 95\% \CL expected and observed upper limits set on ${\sigma(\PP\to 2\Pa+\PX)\mathcal{B}^2(\Pa\to 2\PGm)\alphaGen}$ over the range $0.21 < \MPa < 60\GeV$ for the 2018 analysis. Mass ranges that overlap with \JPsi and \PgU resonances are excluded from the search

The model-independent 95\% \CL expected and observed upper limits set on ${\sigma(\PP\to 2\Pa+\PX)\mathcal{B}^2(\Pa\to 2\PGm)\alphaGen}$ over the range $0.21 < \MPa < 60\GeV$ for the combined 2017 and 2018 analyses. Mass ranges that overlap with \JPsi and \PgU resonances are excluded from the search

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Results on Elastic Cross Sections in Proton-Proton Collisions at $\sqrt{s} = 510$ GeV with the STAR Detector at RHIC

The STAR collaboration Abdulhamid, M.I. ; Aboona, B.E. ; Adam, J. ; et al.
Phys.Lett.B 852 (2024) 138601, 2024.
Inspire Record 2704122 DOI 10.17182/hepdata.144920

We report results on an elastic cross section measurement in proton-proton collisions at a center-of-mass energy $\sqrt{s}=510$ GeV, obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section is measured in the four-momentum transfer squared range $0.23 \leq -t \leq 0.67$ GeV$^2$. We find that a constant slope $B$ does not fit the data in the aforementioned $t$ range, and we obtain a much better fit using a second-order polynomial for $B(t)$. The $t$ dependence of $B$ is determined using six subintervals of $t$ in the STAR measured $t$ range, and is in good agreement with the phenomenological models. The measured elastic differential cross section $\mathrm{d}\sigma/\mathrm{dt}$ agrees well with the results obtained at $\sqrt{s} = 546$ GeV for proton--antiproton collisions by the UA4 experiment. We also determine that the integrated elastic cross section within the STAR $t$-range is $\sigma^\mathrm{fid}_\mathrm{el} = 462.1 \pm 0.9 (\mathrm{stat.}) \pm 1.1 (\mathrm {syst.}) \pm 11.6 (\mathrm {scale})$~$\mu\mathrm{b}$.

2 data tables

Top panel: The $pp$ elastic differential cross section $d\sigma/dt$ fitted with an exponential $A e^{-B(t)|t|}$. Bottom panel: Residuals (Data - Fit)/Error. Uncertainties on the data points are smaller than the symbol size. The vertical scale uncertainty of 2.5% is not included in in the full error.

Results of the exponential function $A e^{-B(t)|t|}$ fit to the elastic differential cross section data as well as the integrated fiducial cross section are listed. Also listed are the corresponding values of the statistical and systematic uncertainties. The scale (luminosity and trigger efficiency) uncertainty of 2.5% applicable to the fit parameter $A$ and fiducial cross section $\sigma^\mathrm{fid}_\mathrm{el}$ is not included in the full error.


Measurement of inclusive and differential cross sections for W$^+$W$^-$ production in proton-proton collisions at $\sqrt{s}$ = 13.6 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-SMP-24-001, 2024.
Inspire Record 2796231 DOI 10.17182/hepdata.150773

Measurements at $\sqrt{s}$ = 13.6 TeV of the opposite-sign W boson pair production cross section in proton-proton collisions are presented. The data used in this study were collected with the CMS detector at the CERN LHC in 2022, and correspond to an integrated luminosity of 34.8 fb$^{-1}$. Events are selected by requiring one electron and one muon of opposite charge. A maximum likelihood fit is performed on signal- and background-enriched data categories defined by the flavour and charge of the leptons, the number of jets, and number of jets originating from b quarks. An inclusive W$^+$W$^-$ production cross section of 125.7 $\pm$ 5.6 pb is measured, in agreement with standard model predictions. Cross sections are also reported in a fiducial region close to that of the detector acceptance, both inclusively and differentially, as a function of the jet multiplicity in the event. For first time in proton-proton collisions, WW events with at least two reconstructed jets are studied and compared with recent theoretical predictions.

6 data tables

Summary of inclusive cross section.

Relative systematic uncertainties in the total cross section measurement.

Measured fraction of events for $N_j = 0, 1, \geq 2$ jets. The total uncertainty is reported.

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A search for top-squark pair production, in final states containing a top quark, a charm quark and missing transverse momentum, using the 139 fb$^{-1}$ of $pp$ collision data collected by the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
JHEP 07 (2024) 250, 2024.
Inspire Record 2759516 DOI 10.17182/hepdata.144439

This paper presents a search for top-squark pair production in final states with a top quark, a charm quark and missing transverse momentum. The data were collected with the ATLAS detector during LHC Run 2 and corresponds to an integrated luminosity of 139fb$^{-1}$ of proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV. The analysis is motivated by an extended Minimal Supersymmetric Standard Model featuring a non-minimal flavour violation in the second- and third-generation squark sector. The top squark in this model has two possible decay modes, either $\tilde{t}_1 \rightarrow c\tilde{\chi}_1^0$ or $\tilde{t}_1\rightarrow t\tilde{\chi}_1^0$, where the $\tilde{\chi}_1^0$ is undetected. The analysis is optimised assuming that both of the decay modes are equally probable, leading to the most likely final state of $tc + E_{\text{T}}^{\text{miss}}$. Good agreement is found between the Standard Model expectation and the data in the search regions. Exclusion limits at 95% CL are obtained in the $m(\tilde{t}_1)$ vs $m(\tilde{\chi}_1^0)$ plane and, in addition, limits on the branching ratio of the $\tilde{t}_1\rightarrow t\tilde{\chi}_1^0$ decay as a function of $m(\tilde{t}_1)$ are also produced. Top-squark masses of up to 800 GeV are excluded for scenarios with light neutralinos, and top-squark masses up to 600 GeV are excluded in scenarios where the neutralino and the top squark are almost mass degenerate.

66 data tables

<b>- - - - - - - - Overview of HEPData Record - - - - - - - -</b> <br><br> <b>Exclusion contours:</b> <ul> <li><a href="?table=mass_obs">Observed exclusion contour in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=mass_exp">Expected exclusion contour in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=mass_band_1">$\pm1\sigma$ exclusion contour in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=mass_band_2">$\pm1\sigma$ exclusion contour in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=br_m1_obs">Observed exclusion contour in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$</a> <li><a href="?table=br_m1_exp">Expected exclusion contour in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$</a> <li><a href="?table=br_m1_band_1">$\pm1\sigma$ exclusion contour in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$</a> <li><a href="?table=br_m1_band_2">$\pm1\sigma$ exclusion contour in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$</a> </ul> <b>Upper limits:</b> <ul> <li><a href="?table=mass_upperLimits_obs">Observed upper limits on the top-spartner pair production cross-section at the 95% CL in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=br_m1_upperLimits_obs">Observed upper limits on the top-spartner pair production cross-section at the 95% CL in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$.</a> <li><a href="?table=mass_upperLimits_exp">Expected upper limits on the top-spartner pair production cross-section at the 95% CL in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$</a> <li><a href="?table=br_m1_upperLimits_exp">Expected upper limits on the top-spartner pair production cross-section at the 95% CL in the $m_{\tilde{t}_1} - $BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1)$ plane, assuming $m_{\tilde\chi^0_1} = 1 \mathrm{GeV}$.</a> </ul> <b>Kinematic distributions:</b> <ul> <li><a href="?table=SRA_ntop">SRA region number of top-tagged jets distribution</a> <li><a href="?table=SRA_mttwo">SRA region $m_{\mathrm{T2}}(j^{b}_{R=1.0}, c)$ distribution</a> <li><a href="?table=SRB_ptc">SRB region leading c-tagged jet $p_{\mathrm{T}}$</a> <li><a href="?table=SRB_mtj">SRB region $m_{\mathrm{T}}(j, E_{\mathrm{T}}^{\mathrm{miss}})_{\mathrm{close}}$ distribution</a> <li><a href="?table=SRC_metsig">SRC region missing transverse momentum significance distribution</a> <li><a href="?table=SRC_mtj">SRC region $m_{\mathrm{T}}(j, E_{\mathrm{T}}^{\mathrm{miss}})_{\mathrm{close}}$ distribution</a> <li><a href="?table=SRD_NN">SRD NN signal score distribution</a> <li><a href="?table=SRD_meff">SRD $m_{\mathrm{eff}}$ distribution</a> </ul> <b>Pull distributions:</b> <ul> <li><a href="?table=SRABCPull">Pull plots showing the SRA, SRB and SRC post-fit data and SM agreement using the background-only fit configuration</a> <li><a href="?table=SRDPull">Pull plots showing the SRD post-fit data and SM agreement using the background-only fit configuration</a> </ul> <b>Cut flows:</b> <ul> <li><a href="?table=cutflow_SRA">Cutflow of 3 signal points in the SRA region.</a> <li><a href="?table=cutflow_SRB">Cutflow of 3 signal points in the SRB region.</a> <li><a href="?table=cutflow_SRC">Cutflow of 3 signal points in the SRC region.</a> <li><a href="?table=cutflow_SRD750">Cutflow of 3 signal points in the SRD750 region.</a> <li><a href="?table=cutflow_SRD1000">Cutflow of 3 signal points in the SRD1000 region.</a> <li><a href="?table=cutflow_SRD1250">Cutflow of 3 signal points in the SRD1250 region.</a> <li><a href="?table=cutflow_SRD1500">Cutflow of 3 signal points in the SRD1500 region.</a> <li><a href="?table=cutflow_SRD1750">Cutflow of 3 signal points in the SRD1750 region.</a> <li><a href="?table=cutflow_SRD2000">Cutflow of 3 signal points in the SRD2000 region.</a> </ul> <b>Acceptance and efficiencies:</b> <ul> <li> <b>SRA_bin1:</b> <a href="?table=Acc_SRA_bin1">Acceptance table of the SRA$^{[450,575]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRA_bin1">Efficiency table of the SRA$^{[450,575]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRA_bin2:</b> <a href="?table=Acc_SRA_bin2">Acceptance table of the SRA$^{\geq 575}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRA_bin2">Efficiency table of the SRA$^{\geq 575}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRB_bin1:</b> <a href="?table=Acc_SRB_bin1">Acceptance table of the SRB$^{[100,150]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRB_bin1">Efficiency table of the SRB$^{[100,150]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRB_bin2:</b> <a href="?table=Acc_SRB_bin2">Acceptance table of the SRB$^{[150,400]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRB_bin2">Efficiency table of the SRB$^{[150,400]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRB_bin3:</b> <a href="?table=Acc_SRB_bin3">Acceptance table of the SRB$^{\geq 400}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRB_bin3">Efficiency table of the SRB$^{\geq 400}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRC_bin1:</b> <a href="?table=Acc_SRC_bin1">Acceptance table of the SRC$^{[100,150]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRC_bin1">Efficiency table of the SRC$^{[100,150]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRC_bin2:</b> <a href="?table=Acc_SRC_bin2">Acceptance table of the SRC$^{[150,300]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRC_bin2">Efficiency table of the SRC$^{[150,300]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRC_bin3:</b> <a href="?table=Acc_SRC_bin3">Acceptance table of the SRC$^{[300,500]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRC_bin3">Efficiency table of the SRC$^{[300,500]}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRC_bin4:</b> <a href="?table=Acc_SRC_bin4">Acceptance table of the SRC$^{\geq 500}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRC_bin4">Efficiency table of the SRC$^{\geq 500}$ in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin1:</b> <a href="?table=Acc_SRD_bin1">Acceptance table of the SRD750 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin1">Efficiency table of the SRD750 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin2:</b> <a href="?table=Acc_SRD_bin2">Acceptance table of the SRD1000 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin2">Efficiency table of the SRD1000 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin3:</b> <a href="?table=Acc_SRD_bin3">Acceptance table of the SRD1250 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin3">Efficiency table of the SRD1250 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin4:</b> <a href="?table=Acc_SRD_bin4">Acceptance table of the SRD1500 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin4">Efficiency table of the SRD1500 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin5:</b> <a href="?table=Acc_SRD_bin5">Acceptance table of the SRD1750 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin5">Efficiency table of the SRD1750 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <li> <b>SRD_bin6:</b> <a href="?table=Acc_SRD_bin6">Acceptance table of the SRD2000 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> <a href="?table=Eff_SRD_bin6">Efficiency table of the SRD2000 in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.</a> </ul> <b>Truth Code snippets</b> are available under "Resources" (purple button on the left)

Observed exclusion limits at the 95% CL in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$.

Observed exclusion limits at the 95% CL in the $\tilde{t}_1 - \tilde\chi^0_1$ mass plane, assuming BR$(\tilde{t}_1 \rightarrow t + \tilde\chi^0_1) = 0.5$ and a $+1 \sigma$ deviation of the NNLO+NNLL theoretical cross-section of a $\tilde{t}_1$ pair-production.

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Measurement of the $\mathrm{t\bar{t}}$H and tH production rates in the H $\to$$\mathrm{b\bar{b}}$ decay channel using proton-proton collision data at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-HIG-19-011, 2024.
Inspire Record 2808025 DOI 10.17182/hepdata.152799

An analysis of the production of a Higgs boson (H) in association with a top quark-antiquark pair ($\mathrm{t\bar{t}}$H) or a single top quark (tH) is presented. The Higgs boson decay into a bottom quark-antiquark pair (H $\to$$\mathrm{b\bar{b}}$) is targeted, and three different final states of the top quark decays are considered, defined by the number of leptons (electrons or muons) in the event. The analysis utilises proton-proton collision data collected at the CERN LHC with the CMS experiment at $\sqrt{s}$ = 13 TeV in 2016-2018, which correspond to an integrated luminosity of 138 fb$^{-1}$. The observed $\mathrm{t\bar{t}}$H production rate relative to the standard model expectation is 0.33 $\pm$ 0.26 = 0.33 $\pm$ 0.17 (stat) $\pm$ 0.21 (syst). Additionally, the $\mathrm{t\bar{t}}$H production rate is determined in intervals of Higgs boson transverse momentum. An upper limit at 95% confidence level is set on the tH production rate of 14.6 times the standard model prediction, with an expectation of 19.3$^{+9.2}_{-6.0}$. Finally, constraints are derived on the strength and structure of the coupling between the Higgs boson and the top quark from simultaneous extraction of the $\mathrm{t\bar{t}}$H and tH production rates, and the results are combined with those obtained in other Higgs boson decay channels.

14 data tables

Best fit results of the ttH signal-strength modifier in each channel, in each year, and in the combination of all channels and years. Uncertainties are correlated between the channels and years.

Likelihood-ratio test statistic as a function of the ttH strength modifiers $\mu_{ttH}$ and the $ttB$ background normalisation. The observed best fit point is $(\mu_{ttH}, ttB) = (0.33, 1.19)$.

Best fit results of the ttH signal-strength modifiers in the different Higgs pT bins of the STXS measurement.

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Studies of the energy dependence of diboson polarization fractions and the Radiation Amplitude Zero effect in WZ production with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
Phys.Rev.Lett. 133 (2024) 101802, 2024.
Inspire Record 2762099 DOI 10.17182/hepdata.149992

This Letter presents the first study of the energy-dependence of diboson polarization fractions in $WZ \rightarrow \ell\nu \ell'\ell'~(\ell, \ell'=e, \mu)$ production. The data set used corresponds to an integrated luminosity of 140 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the ATLAS detector. Two fiducial regions with an enhanced presence of events featuring two longitudinally-polarized bosons are defined. A non-zero fraction of events with two longitudinally-polarized bosons is measured with an observed significance of 5.3 standard deviations in the region with $100<p_T^Z\leq200$ GeV and 1.6 standard deviations in the region with $p_T^Z>200$ GeV, where $p_T^Z$ is the transverse momentum of the $Z$ boson. This Letter also reports the first study of the Radiation Amplitude Zero effect. Events with two transversely-polarized bosons are analyzed for the $\Delta Y(\ell_W Z)$ and $\Delta Y(WZ)$ distributions defined respectively as the rapidity difference between the lepton from the $W$ boson decay and the $Z$ boson and the rapidity difference between the $W$ boson and the $Z$ boson. Significant suppression of events near zero is observed in both distributions. Unfolded $\Delta Y(\ell_W Z)$ and $\Delta Y(WZ)$ distributions are also measured and compared to theoretical predictions.

45 data tables

Polarization fractions in the region with $100<p_T^Z\leq200$ GeV using three unconstrained parameters.

Polarization fractions in the region with $p_T^Z>200$ GeV using three unconstrained parameters.

Fraction of events where both bosons are longitudinally polarized in the region with $100<p_T^Z\leq200$ GeV using two unconstrained parameters.

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Version 2
Precise Measurement of the $e^+ e^- \to \pi^+\pi^- (\gamma)$ Cross Section with the Initial-State Radiation Method at BABAR

The BaBar collaboration Lees, J.P. ; Poireau, V. ; Tisserand, V. ; et al.
Phys.Rev.D 86 (2012) 032013, 2012.
Inspire Record 1114155 DOI 10.17182/hepdata.115140

A precise measurement of the cross section of the process $e^+e^-\to\pi^+\pi^-(\gamma)$ from threshold to an energy of 3GeV is obtained with the initial-state radiation (ISR) method using 232fb$^{-1}$ of data collected with the BaBar detector at $e^+e^-$ center-of-mass energies near 10.6GeV. The ISR luminosity is determined from a study of the leptonic process $e^+e^-\to\mu^+\mu^-(\gamma)\gamma_{\rm ISR}$, which is found to agree with the next-to-leading-order QED prediction to within 1.1%. The cross section for the process $e^+e^-\to\pi^+\pi^-(\gamma)$ is obtained with a systematic uncertainty of 0.5% in the dominant $\rho$ resonance region. The leading-order hadronic contribution to the muon magnetic anomaly calculated using the measured $\pi\pi$ cross section from threshold to 1.8GeV is $(514.1 \pm 2.2({\rm stat}) \pm 3.1({\rm syst}))\times 10^{-10}$.

3 data tables

Bare cross-section $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ The cross section values (nb) for 337 CM energy intervals (GeV) from 0.3 to 3 GeV. The cross section is bare (excluding vacuum polarization) and includes the emission of final state photons. ***WARNING*** The quoted errors are from the diagonal elements of the statistical covariance matrix (reported on the Table titled "Bare cross-section statistical covariance") and added quadratically with the systematic uncertainties (reported in the Table titled "Bare cross-section systematic uncertainties"). These errors can be used when plotting the results as they are representative of the precision achieved. However, any calculation involving the cross section over some energy range MUST use, to be meaningful, the full statistical covariance matrix and the proper correlations of the systematic uncertainties. ***WARNING*** The Bare cross-section statistical covariance is reported as additional resource in YAML, since its size exceeds the maximum size of 10 MB for the library hepdata_lib. It is a statistical covariance matrix, for 337x337 CM energy intervals (GeV), from 0.3 to 3 GeV, matching the ones of this table.

Bare cross-section $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ systematic uncertainties contributions and total systematic uncertainties, for 337 CM energy intervals (GeV), from 0.3 to 3 GeV. All systematics contributions are each 100% correlated in all energy bins.

Bare cross-section $e^+e^-\rightarrow\pi^+\pi^-(\gamma)$ statistical covariance matrix, for 337x337 CM energy intervals (GeV), from 0.3 to 3 GeV.


Inclusive and differential cross-section measurements of $t\bar{t}Z$ production in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector, including EFT and spin-correlation interpretations

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
JHEP 07 (2024) 163, 2024.
Inspire Record 2744513 DOI 10.17182/hepdata.146693

Measurements of both the inclusive and differential production cross sections of a top-quark-top-antiquark pair in association with a $Z$ boson ($t\bar{t}Z$) are presented. Final states with two, three or four isolated leptons (electrons or muons) are targeted. The measurements use the data recorded by the ATLAS detector in $pp$ collisions at $\sqrt{s}=13$ TeV at the Large Hadron Collider during the years 2015-2018, corresponding to an integrated luminosity of $140$ fb$^{-1}$. The inclusive cross section is measured to be $\sigma_{t\bar{t}Z}= 0.86 \pm 0.04~\mathrm{(stat.)} \pm 0.04~\mathrm{(syst.)}~$pb and found to be in agreement with the most advanced Standard Model predictions. The differential measurements are presented as a function of a number of observables that probe the kinematics of the $t\bar{t}Z$ system. Both the absolute and normalised differential cross-section measurements are performed at particle level and parton level for specific fiducial volumes, and are compared with NLO+NNLL theoretical predictions. The results are interpreted in the framework of Standard Model effective field theory and used to set limits on a large number of dimension-6 operators involving the top quark. The first measurement of spin correlations in $t\bar{t}Z$ events is presented: the results are in agreement with the Standard Model expectations, and the null hypothesis of no spin correlations is disfavoured with a significance of $1.8$ standard deviations.

385 data tables

All the entries of this HEP data record are listed. Figure and Table numbers are the same as in the paper.

Definition of the dilepton signal regions.

Definition of the trilepton signal regions.

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Measurement of $\sigma(e^+ e^- \to \pi^+ \pi^-)$ from threshold to 0.85 GeV$^2$ using Initial State Radiation with the KLOE detector

The KLOE collaboration Ambrosino, F. ; Antonelli, A. ; Antonelli, M. ; et al.
Phys.Lett.B 700 (2011) 102-110, 2011.
Inspire Record 859660 DOI 10.17182/hepdata.96268

We have measured the cross section of the radiative process e+e- -> pi+pi-gamma with the KLOE detector at the Frascati phi-factory DAPHNE, from events taken at a CM energy W=1 GeV. Initial state radiation allows us to obtain the cross section for e+e- -> pi+pi-, the pion form factor |F_pi|^2 and the dipion contribution to the muon magnetic moment anomaly, Delta a_mu^{pipi} = (478.5+-2.0_{stat}+-5.0_{syst}+-4.5_{th}) x 10^{-10} in the range 0.1 < M_{pipi}^2 < 0.85 GeV^2, where the theoretical error includes a SU(3) ChPT estimate of the uncertainty on photon radiation from the final pions. The discrepancy between the Standard Model evaluation of a_mu and the value measured by the Muon g-2 collaboration at BNL is confirmed.

15 data tables

Differential cross section for $e^+e^-\rightarrow\pi^+\pi^-\gamma$, with $50^o<\theta_\gamma<130^o$

Statistical covariance matrix for differential cross section for $e^+e^-\rightarrow\pi^+\pi^-\gamma$, with $50^o<\theta_\gamma<130^o$

Inverse statistical covariance matrix for differential cross section for $e^+e^-\rightarrow\pi^+\pi^-\gamma$, with $50^o<\theta_\gamma<130^o$

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Measurement and interpretation of same-sign $W$ boson pair production in association with two jets in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abeling, Kira ; et al.
JHEP 04 (2024) 026, 2024.
Inspire Record 2729396 DOI 10.17182/hepdata.141650

This paper presents the measurement of fiducial and differential cross sections for both the inclusive and electroweak production of a same-sign $W$-boson pair in association with two jets ($W^\pm W^\pm jj$) using 139 fb$^{-1}$ of proton-proton collision data recorded at a centre-of-mass energy of $\sqrt{s}=13$ TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed by selecting two same-charge leptons, electron or muon, and at least two jets with large invariant mass and a large rapidity difference. The measured fiducial cross sections for electroweak and inclusive $W^\pm W^\pm jj$ production are $2.92 \pm 0.22\, \text{(stat.)} \pm 0.19\, \text{(syst.)}$ fb and $3.38 \pm 0.22\, \text{(stat.)} \pm 0.19\, \text{(syst.)}$ fb, respectively, in agreement with Standard Model predictions. The measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confidence level intervals on dimension-8 operators. A search for doubly charged Higgs bosons $H^{\pm\pm}$ that are produced in vector-boson fusion processes and decay into a same-sign $W$ boson pair is performed. The largest deviation from the Standard Model occurs for an $H^{\pm\pm}$ mass near 450 GeV, with a global significance of 2.5 standard deviations.

30 data tables

Fiducial differential cross section of the electroweak $W^\pm W^\pm jj$ production as a function of $m_{\ell\ell}$. The correlation of uncertainties of the measured cross section across bins is presented in Table 11.

Fiducial differential cross section of the electroweak $W^\pm W^\pm jj$ production as a function of $m_{\mathrm{T}}$. The correlation of uncertainties of the measured cross section across bins is presented in Table 12.

Fiducial differential cross section of the electroweak $W^\pm W^\pm jj$ production as a function of $m_{\mathrm{jj}}$. The correlation of uncertainties of the measured cross section across bins is presented in Table 13.

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