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Differential cross-section measurements of $D^{\pm}$ and $D_{s}^{\pm}$ meson production in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 07 (2025) 086, 2025.
Inspire Record 2862073 DOI 10.17182/hepdata.155981

The production of $D^{\pm}$ and $D_{s}^{\pm}$ charmed mesons is measured using the $D^{\pm}/D_{s}^{\pm} \to ϕ(μμ)π^{\pm}$ decay channel with 137 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider during the years 2016-2018. The charmed mesons are reconstructed in the range of transverse momentum $12 < p_\mathrm{T} < 100$ GeV and pseudorapidity $|η| < 2.5$. The differential cross-sections are measured as a function of transverse momentum and pseudorapidity, and compared with next-to-leading-order QCD predictions. The predictions are found to be consistent with the measurements in the visible kinematic region within the large theoretical uncertainties.

6 data tables

The measured differential cross-sections and the predictions from GM-VFNS and FONLL calculations for the $D^\pm$ meson in bins of $|\eta|$. The statistical, systematic (excluding branching ratio) and branching ratio uncertainties are shown separately for data, while the total theory uncertainties are shown for GM-VFNS and FONLL.

The measured differential cross-sections and the predictions from GM-VFNS and FONLL calculations for the $D^\pm$ meson in bins of $p_T$ for $|\eta| < 2.5$. The statistical, systematic (excluding branching ratio) and branching ratio uncertainties are shown separately for data, while the total theory uncertainties are shown for GM-VFNS and FONLL.

The measured differential cross-sections and the predictions from the GM-VFNS calculation for the $D_s^\pm$ meson in bins of $|\eta|$. The statistical, systematic (excluding branching ratio) and branching ratio uncertainties are shown separately for data, while the total theory uncertainties are shown for GM-VFNS.

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Improved reconstruction of highly boosted $\tau$-lepton pairs in the $\tau\tau\rightarrow(\mu\nu_{\mu}\nu_{\tau})({hadrons}+\nu_{\tau})$ decay channels with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
Eur.Phys.J.C 85 (2025) 706, 2025.
Inspire Record 2861685 DOI 10.17182/hepdata.157879

This paper presents a new $τ$-lepton reconstruction and identification procedure at the ATLAS detector at the Large Hadron Collider, which leads to significantly improved performance in the case of physics processes where a highly boosted pair of $τ$-leptons is produced and one $τ$-lepton decays into a muon and two neutrinos ($τ_μ$), and the other decays into hadrons and one neutrino ($τ_{had}$). By removing the muon information from the signals used for reconstruction and identification of the $τ_{had}$ candidate in the boosted pair, the efficiency is raised to the level expected for an isolated $τ_{had}$. The new procedure is validated by selecting a sample of highly boosted $Z\rightarrowτ_μτ_{had}$ candidates from the data sample of $140$${fb}^{-1}$ of proton-proton collisions at $13$ TeV recorded with the ATLAS detector. Good agreement is found between data and simulation predictions in both the $Z\rightarrowτ_μτ_{had}$ signal region and in a background validation region. The results presented in this paper demonstrate the effectiveness of the $τ_{had}$ reconstruction with muon removal in enhancing the signal sensitivity of the boosted $τ_μτ_{had}$ channel at the ATLAS detector.

22 data tables

The distribution of the TauID jet RNN score for $\tau_\mathrm{had}^{\mu\mkern-10mu\backslash}$ in the SR. `$Z(\rightarrow\tau\tau)$+jets' represents the contributions from the signal process. `Top' represents the predicted contributions from the $t\bar{t}$, single-top-quark, and $tW$ processes. `Diboson' indicates the contributions from $WW$, $WZ$, and $ZZ$ processes. `Other' includes the contributions from the $Z(\rightarrow\ell\ell)$+jets, $W$+jets, and Higgs boson processes. The uncertainties shown include both statistical and systematic sources.

The distribution of the TauID jet RNN score for $\tau_\mathrm{had}^{\mu\mkern-10mu\backslash}$ in the VR. `$Z(\rightarrow\tau\tau)$+jets' represents the contributions from the signal process. `Top' represents the predicted contributions from the $t\bar{t}$, single-top-quark, and $tW$ processes. `Diboson' indicates the contributions from $WW$, $WZ$, and $ZZ$ processes. `Other' includes the contributions from the $Z(\rightarrow\ell\ell)$+jets, $W$+jets, and Higgs boson processes. The uncertainties shown include both statistical and systematic sources.

The distribution of the $p_\mathrm{T}{}_{\mu\mathrm{-had}}^\mathrm{col}$ in the SR. `$Z(\rightarrow\tau\tau)+\text{jets}$' represents the contributions from the signal process. `Diboson' indicates the contributions from $WW$, $WZ$, and $ZZ$ processes. `Top' represents the predicted contributions from the $t\bar{t}$, single-top-quark, and $tW$ processes. `Other' includes the contributions from the $Z(\rightarrow\ell\ell)$+jets, $W$+jets, and Higgs boson processes. The uncertainties shown include both statistical and systematic sources.

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Precision measurement of the $B^{0}$ meson lifetime using $B^{0} \rightarrow J/\psi K^{*0}$ decays with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
Eur.Phys.J.C 85 (2025) 736, 2025.
Inspire Record 2849026 DOI 10.17182/hepdata.158278

A measurement of the $B^{0}$ meson lifetime and related properties using $B^0 \to J/ψK^{*0}$ decays in data from 13 TeV proton-proton collisions with an integrated luminosity of 140 fb$^{-1}$ recorded by the ATLAS detector at the LHC is presented. The measured effective lifetime is $$ τ= 1.5053 \pm 0.0012 ~\mathrm{(stat.)} \pm 0.0035 ~\mathrm{(syst.)~ps}. $$ The average decay width extracted from the effective lifetime, using parameters from external sources, is $$ Γ_d = 0.6639 \pm 0.0005 ~\mathrm{(stat.)} \pm 0.0016 ~\mathrm{(syst.)}\pm 0.0038 ~\textrm{(ext.)} \textrm{ ps}^{-1}, $$ where the uncertainties are statistical, systematic and from external sources. The earlier ATLAS measurement of $Γ_s$ in the $B^0_s \to J/ψϕ$ decay was used to derive a value for the ratio of the average decay widths $Γ_d$ and $Γ_s$ for $B^{0}$ and $B_s^{0}$ mesons respectively, of $$ \frac{Γ_d }{Γ_s } = 0.9905 \pm 0.0022 ~\textrm{(stat.)} \pm 0.0036 ~\textrm{(syst.)} \pm 0.0057 ~\textrm{(ext.)}. $$ The measured lifetime, average decay width and decay width ratio are in agreement with theoretical predictions and with measurements by other experiments. This measurement provides the most precise result of the effective lifetime of the $B^{0}$ meson to date.

3 data tables

The measured effective lifetime for the $B^0 \rightarrow J/\psi\,K^{*0}$ decay.

The measured average decay width $\Gamma_{d}\,$ extracted from the average lifetime.

The measured ratio $\Gamma_{d} / \Gamma_{s}\,$ of the average decay widths.


Search for supersymmetry in final states with missing transverse momentum and charm-tagged jets using 139 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 02 (2025) 193, 2025.
Inspire Record 2842361 DOI 10.17182/hepdata.155678

The paper presents a search for supersymmetric particles produced in proton-proton collisions at $\sqrt{s}=$ 13 TeV and decaying into final states with missing transverse momentum and jets originating from charm quarks. The data were taken with the ATLAS detector at the Large Hadron Collider at CERN from 2015 to 2018 and correspond to an integrated luminosity of 139 fb$^{-1}$. No significant excess of events over the expected Standard Model background expectation is observed in optimized signal regions, and limits are set on the production cross-sections of the supersymmetric particles. Pair production of charm squarks or top squarks, each decaying into a charm quark and the lightest supersymmetric particle $\tilde{\chi}^0_1$, is excluded at 95% confidence level for squarks with masses up to 900 GeV for scenarios where the mass of $\tilde{\chi}^0_1$ is below 50 GeV. Additionally, the production of leptoquarks with masses up to 900 GeV is excluded for the scenario where up-type leptoquarks decay into a charm quark and a neutrino. Model-independent limits on cross-sections and event yields for processes beyond the Standard Model are also reported.

160 data tables

Summary of material in this HEPData record. <br/><br/> Truth Code snippets, SLHA files, Madgraph process cards and UFO files for the leptoquark models are available under "Additional Resources" (purple button on the left). <br/><br/> <b>Contours:</b> <ul> SUSY exclusion limits (best-expected SR combination) <ul> <a href="155678?version=1&table=Contour1">Expected</a> <a href="155678?version=1&table=Contour3">+1$\sigma$</a> <a href="155678?version=1&table=Contour2">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour4">Observed</a> <a href="155678?version=1&table=Contour5">+1$\sigma$</a> <a href="155678?version=1&table=Contour6">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (best-expected SR combination) as a function of $\Delta m(\tilde{t}_1,\tilde{\chi}_1^0)$ <ul> <a href="155678?version=1&table=Contour7">Expected</a> <a href="155678?version=1&table=Contour9">+1$\sigma$</a> <a href="155678?version=1&table=Contour8">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour10">Observed</a> <a href="155678?version=1&table=Contour11">+1$\sigma$</a> <a href="155678?version=1&table=Contour12">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-HM1) <ul> <a href="155678?version=1&table=Contour15">Expected</a> <a href="155678?version=1&table=Contour14">+1$\sigma$</a> <a href="155678?version=1&table=Contour13">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour18">Observed</a> <a href="155678?version=1&table=Contour16">+1$\sigma$</a> <a href="155678?version=1&table=Contour17">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-HM2) <ul> <a href="155678?version=1&table=Contour21">Expected</a> <a href="155678?version=1&table=Contour20">+1$\sigma$</a> <a href="155678?version=1&table=Contour19">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour24">Observed</a> <a href="155678?version=1&table=Contour22">+1$\sigma$</a> <a href="155678?version=1&table=Contour23">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-HM3) <ul> <a href="155678?version=1&table=Contour27">Expected</a> <a href="155678?version=1&table=Contour26">+1$\sigma$</a> <a href="155678?version=1&table=Contour25">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour30">Observed</a> <a href="155678?version=1&table=Contour28">+1$\sigma$</a> <a href="155678?version=1&table=Contour29">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-Comp1) <ul> <a href="155678?version=1&table=Contour33">Expected</a> <a href="155678?version=1&table=Contour32">+1$\sigma$</a> <a href="155678?version=1&table=Contour31">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour36">Observed</a> <a href="155678?version=1&table=Contour34">+1$\sigma$</a> <a href="155678?version=1&table=Contour35">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-Comp2) <ul> <a href="155678?version=1&table=Contour39">Expected</a> <a href="155678?version=1&table=Contour38">+1$\sigma$</a> <a href="155678?version=1&table=Contour37">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour42">Observed</a> <a href="155678?version=1&table=Contour40">+1$\sigma$</a> <a href="155678?version=1&table=Contour41">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-Comp3) <ul> <a href="155678?version=1&table=Contour45">Expected</a> <a href="155678?version=1&table=Contour44">+1$\sigma$</a> <a href="155678?version=1&table=Contour43">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour48">Observed</a> <a href="155678?version=1&table=Contour46">+1$\sigma$</a> <a href="155678?version=1&table=Contour47">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (SR-Comp-1c) <ul> <a href="155678?version=1&table=Contour50">Expected</a> <a href="155678?version=1&table=Contour49">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (scan over branching fraction for $m(\tilde{\chi}_1^0)=1$ GeV) <ul> <a href="155678?version=1&table=Contour51">Expected</a> <a href="155678?version=1&table=Contour53">+1$\sigma$</a> <a href="155678?version=1&table=Contour52">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour54">Observed</a> <a href="155678?version=1&table=Contour55">+1$\sigma$</a> <a href="155678?version=1&table=Contour56">-1$\sigma$</a> <br/> </ul> SUSY exclusion limits (scan over branching fraction for $m(\tilde{\chi}_1^0)=200$ GeV) <ul> <a href="155678?version=1&table=Contour57">Expected</a> <a href="155678?version=1&table=Contour59">+1$\sigma$</a> <a href="155678?version=1&table=Contour58">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour60">Observed</a> <a href="155678?version=1&table=Contour61">+1$\sigma$</a> <a href="155678?version=1&table=Contour62">-1$\sigma$</a> <br/> </ul> $\mathrm{LQ}^\mathrm{u}_{21}$ exclusion limits <ul> <a href="155678?version=1&table=Contour65">Expected</a> <a href="155678?version=1&table=Contour64">+1$\sigma$</a> <a href="155678?version=1&table=Contour63">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour68">Observed</a> <a href="155678?version=1&table=Contour66">+1$\sigma$</a> <a href="155678?version=1&table=Contour67">-1$\sigma$</a> <br/> </ul> $\mathrm{LQ}^\mathrm{u}_{22}$ exclusion limits <ul> <a href="155678?version=1&table=Contour71">Expected</a> <a href="155678?version=1&table=Contour70">+1$\sigma$</a> <a href="155678?version=1&table=Contour69">-1$\sigma$</a> <br/> <a href="155678?version=1&table=Contour74">Observed</a> <a href="155678?version=1&table=Contour72">+1$\sigma$</a> <a href="155678?version=1&table=Contour73">-1$\sigma$</a> <br/> </ul> </ul> <b>Cross-section upper limits:</b> <ul> SUSY signals (best-expected SR combination): <a href="155678?version=1&table=Cross-sectionupperlimit1">Observed</a> <br/> $\mathrm{LQ}^\mathrm{u}_{21}$ (combined High-Mass SRs): <a href="155678?version=1&table=Cross-sectionupperlimit2">Observed</a> <br/> $\mathrm{LQ}^\mathrm{u}_{22}$ (combined High-Mass SRs): <a href="155678?version=1&table=Cross-sectionupperlimit3">Observed</a> <br/> $U(1)$ pair (min) (combined High-Mass SRs): <a href="155678?version=1&table=Cross-sectionupperlimit6">Expected</a> <a href="155678?version=1&table=Cross-sectionupperlimit5">+1$\sigma$</a> <a href="155678?version=1&table=Cross-sectionupperlimit4">-1$\sigma$</a> <a href="155678?version=1&table=Cross-sectionupperlimit7">Observed</a> <br/> $U(1)$ pair (YM) (combined High-Mass SRs): <a href="155678?version=1&table=Cross-sectionupperlimit10">Expected</a> <a href="155678?version=1&table=Cross-sectionupperlimit9">+1$\sigma$</a> <a href="155678?version=1&table=Cross-sectionupperlimit8">-1$\sigma$</a> <a href="155678?version=1&table=Cross-sectionupperlimit11">Observed</a> <br/> </ul> <b>Signal region distributions:</b> <ul> <a href="155678?version=1&table=SRdistribution2">$E_\mathrm{T}^\mathrm{miss}$ Sig. in SR-HM1</a> <br/> <a href="155678?version=1&table=SRdistribution3">$m_\mathrm{T}^\mathrm{min}(c)$ in SR-HM2</a> <br/> <a href="155678?version=1&table=SRdistribution4">$R_\mathrm{ISR}$ in SR-Comp1</a> <br/> <a href="155678?version=1&table=SRdistribution5">$R_\mathrm{ISR}$ in SR-Comp2</a> <br/> <a href="155678?version=1&table=SRdistribution6">$R_\mathrm{ISR}$ in SR-Comp3</a> <br/> <a href="155678?version=1&table=SRdistribution1">$R_\mathrm{ISR}$ in SR-Comp-1c</a> <br/> </ul> <b>Acceptances:</b> <ul> SUSY signals: <a href="155678?version=1&table=Acceptance2">SR-HM1</a> <a href="155678?version=1&table=Acceptance3">SR-HM2</a> <a href="155678?version=1&table=Acceptance4">SR-HM3</a> <a href="155678?version=1&table=Acceptance5">SR-HM-Disc</a> <a href="155678?version=1&table=Acceptance6">SR-Comp1</a> <a href="155678?version=1&table=Acceptance7">SR-Comp2</a> <a href="155678?version=1&table=Acceptance8">SR-Comp3</a> <a href="155678?version=1&table=Acceptance1">SR-Comp-1c</a> <br/> $\mathrm{LQ}^\mathrm{u}_{21}$: <a href="155678?version=1&table=Acceptance9">SR-HM1</a> <a href="155678?version=1&table=Acceptance10">SR-HM2</a> <a href="155678?version=1&table=Acceptance11">SR-HM3</a> <a href="155678?version=1&table=Acceptance12">SR-HM-Disc</a> <br/> $\mathrm{LQ}^\mathrm{u}_{22}$: <a href="155678?version=1&table=Acceptance13">SR-HM1</a> <a href="155678?version=1&table=Acceptance14">SR-HM2</a> <a href="155678?version=1&table=Acceptance15">SR-HM3</a> <a href="155678?version=1&table=Acceptance16">SR-HM-Disc</a> <br/> $U(1)$ pair (min): <a href="155678?version=1&table=Acceptance17">SR-HM1</a> <a href="155678?version=1&table=Acceptance18">SR-HM2</a> <a href="155678?version=1&table=Acceptance19">SR-HM3</a> <a href="155678?version=1&table=Acceptance20">SR-HM-Disc</a> <br/> $U(1)$ pair (YM): <a href="155678?version=1&table=Acceptance21">SR-HM1</a> <a href="155678?version=1&table=Acceptance22">SR-HM2</a> <a href="155678?version=1&table=Acceptance23">SR-HM3</a> <a href="155678?version=1&table=Acceptance24">SR-HM-Disc</a> <br/> </ul> <b>Efficiencies:</b> <ul> $U(1)$ pair (min): <a href="155678?version=1&table=Efficiency1">SR-HM1</a> <a href="155678?version=1&table=Efficiency2">SR-HM2</a> <a href="155678?version=1&table=Efficiency3">SR-HM3</a> <a href="155678?version=1&table=Efficiency4">SR-HM-Disc</a> <br/> $U(1)$ pair (YM): <a href="155678?version=1&table=Efficiency5">SR-HM1</a> <a href="155678?version=1&table=Efficiency6">SR-HM2</a> <a href="155678?version=1&table=Efficiency7">SR-HM3</a> <a href="155678?version=1&table=Efficiency8">SR-HM-Disc</a> <br/> </ul> <b>Acceptance times efficiency:</b> <ul> SUSY signals: <a href="155678?version=1&table=Acceptancetimesefficiency2">SR-HM1</a> <a href="155678?version=1&table=Acceptancetimesefficiency3">SR-HM2</a> <a href="155678?version=1&table=Acceptancetimesefficiency4">SR-HM3</a> <a href="155678?version=1&table=Acceptancetimesefficiency5">SR-HM-Disc</a> <a href="155678?version=1&table=Acceptancetimesefficiency6">SR-Comp1</a> <a href="155678?version=1&table=Acceptancetimesefficiency7">SR-Comp2</a> <a href="155678?version=1&table=Acceptancetimesefficiency8">SR-Comp3</a> <a href="155678?version=1&table=Acceptancetimesefficiency1">SR-Comp-1c</a> <br/> $\mathrm{LQ}^\mathrm{u}_{21}$: <a href="155678?version=1&table=Acceptancetimesefficiency9">SR-HM1</a> <a href="155678?version=1&table=Acceptancetimesefficiency10">SR-HM2</a> <a href="155678?version=1&table=Acceptancetimesefficiency11">SR-HM3</a> <a href="155678?version=1&table=Acceptancetimesefficiency12">SR-HM-Disc</a> <br/> $\mathrm{LQ}^\mathrm{u}_{22}$: <a href="155678?version=1&table=Acceptancetimesefficiency13">SR-HM1</a> <a href="155678?version=1&table=Acceptancetimesefficiency14">SR-HM2</a> <a href="155678?version=1&table=Acceptancetimesefficiency15">SR-HM3</a> <a href="155678?version=1&table=Acceptancetimesefficiency16">SR-HM-Disc</a> <br/> $U(1)$ pair (min): <a href="155678?version=1&table=Acceptancetimesefficiency17">SR-HM1</a> <a href="155678?version=1&table=Acceptancetimesefficiency18">SR-HM2</a> <a href="155678?version=1&table=Acceptancetimesefficiency19">SR-HM3</a> <a href="155678?version=1&table=Acceptancetimesefficiency20">SR-HM-Disc</a> <br/> $U(1)$ pair (YM): <a href="155678?version=1&table=Acceptancetimesefficiency21">SR-HM1</a> <a href="155678?version=1&table=Acceptancetimesefficiency22">SR-HM2</a> <a href="155678?version=1&table=Acceptancetimesefficiency23">SR-HM3</a> <a href="155678?version=1&table=Acceptancetimesefficiency24">SR-HM-Disc</a> <br/> </ul> <b>Cutflow:</b> <ul> SUSY benchmarks: <a href="155678?version=1&table=Cutflow5">SR-HM1</a> <a href="155678?version=1&table=Cutflow6">SR-HM2</a> <a href="155678?version=1&table=Cutflow7">SR-HM3</a> <a href="155678?version=1&table=Cutflow8">SR-HM-Disc</a> <a href="155678?version=1&table=Cutflow2">SR-Comp1</a> <a href="155678?version=1&table=Cutflow3">SR-Comp2</a> <a href="155678?version=1&table=Cutflow4">SR-Comp3</a> <a href="155678?version=1&table=Cutflow1">SR-Comp-1c</a> <br/> LQ benchmarks: <a href="155678?version=1&table=Cutflow9">SR-HM1</a> <a href="155678?version=1&table=Cutflow10">SR-HM2</a> <a href="155678?version=1&table=Cutflow11">SR-HM3</a> <a href="155678?version=1&table=Cutflow12">SR-HM-Disc</a> <br/> </ul>

Expected exclusion limit at 95% CL for pair production of top squarks decaying to charm quarks and neutralinos.

Expected exclusion limit $(-1\sigma)$ at 95% CL for pair production of top squarks decaying to charm quarks and neutralinos.

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Version 2
Search for a light CP-odd Higgs boson decaying into a pair of $\tau$-leptons in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 12 (2024) 126, 2024.
Inspire Record 2836178 DOI 10.17182/hepdata.153948

This paper reports a search for a light CP-odd scalar resonance with a mass of 20 GeV to 90 GeV in 13 TeV proton-proton collision data with an integrated luminosity of 140 fb$^{-1}$ collected with the ATLAS detector at the Large Hadron Collider. The analysis assumes the resonance is produced via gluon-gluon fusion and decays into a $\tau^{+}\tau^{-}$ pair which subsequently decays into a fully leptonic $\mu^{+}\nu_{\mu} \bar{\nu}_{\tau} e^{-} \bar{\nu}_{e} \nu_{\tau}$ or $e^{+}\nu_{e}\bar{\nu}_{\tau} \mu^-\bar{\nu}_{\mu}\nu_{\tau}$ final state. No significant excess of events above the predicted Standard Model background is observed. The results are interpreted within a flavour-aligned two-Higgs-doublet model, and a model-independent cross-section interpretation is also given. Upper limits at 95$%$ confidence level between 3.0 pb and 68 pb are set on the cross-section for producing a CP-odd Higgs boson that decays into a $\tau^+\tau^-$ pair.

10 data tables

Post-fit $m_\mathrm{MMC}$ distribution in the low-mass SR for the $m_A = 20\,\mathrm{GeV}$ signal mass hypothesis. $m_\mathrm{MMC}$ is the mass reconstructed by the Missing Mass Calculator. Processes contributing to the background Others are $Z/\gamma^* \rightarrow ee/\mu\mu$ and SM Higgs. The subscript on the $A\to\tau\tau$ process indicates the mass of the $A$ boson. Total includes all backgrounds and the signal process. The low-mass Signal Region is defined as: - 1 electron and 1 muon with opposite charge - $p_\mathrm{T}$ requirements of the leptons are a combination of the following: - $p_\mathrm{T}^e > 18\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 15\,\mathrm{GeV}$ - $p_\mathrm{T}^e > 10\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 25\,\mathrm{GeV}$ - $p_\mathrm{T}^e > 27\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 10\,\mathrm{GeV}$ - $\vert \eta_e \vert < 2.47$, excluding $1.37 < \vert \eta_e \vert < 1.52$ - $\vert \eta_\mu \vert < 2.7$ - no jets with $b$-quarks - $\Delta R_{\ell\ell} < 0.7$ - $E_\mathrm{T}^\mathrm{miss} > 50\,\mathrm{GeV}$ - $m_\mathrm{T}^\mathrm{tot} = \sqrt{\left(p_\mathrm{T}^e+p_\mathrm{T}^\mu+E_\mathrm{T}^\mathrm{miss}\right)^2-\left(\vec{p}_\mathrm{T}^{\,e}+\vec{p}_\mathrm{T}^{\,\mu}+\vec{E}_\mathrm{T}^{\,\mathrm{miss}}\right)^2} < 45\,\mathrm{GeV}$ - $m_\mathrm{MMC} > 0\,\mathrm{GeV}$

Post-fit $m_\mathrm{MMC}$ distribution in the low-mass SR for the $m_A = 20\,\mathrm{GeV}$ signal mass hypothesis. $m_\mathrm{MMC}$ is the mass reconstructed by the Missing Mass Calculator. Processes contributing to the background Others are $Z/\gamma^* \rightarrow ee/\mu\mu$ and SM Higgs. The subscript on the $A\to\tau\tau$ process indicates the mass of the $A$ boson. Total includes all backgrounds and the signal process. The low-mass Signal Region is defined as: - 1 electron and 1 muon with opposite charge - $p_\mathrm{T}$ requirements of the leptons are a combination of the following: - $p_\mathrm{T}^e > 18\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 15\,\mathrm{GeV}$ - $p_\mathrm{T}^e > 10\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 25\,\mathrm{GeV}$ - $p_\mathrm{T}^e > 27\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 10\,\mathrm{GeV}$ - $\vert \eta_e \vert < 2.47$, excluding $1.37 < \vert \eta_e \vert < 1.52$ - $\vert \eta_\mu \vert < 2.7$ - no jets with $b$-quarks - $\Delta R_{\ell\ell} < 0.7$ - $E_\mathrm{T}^\mathrm{miss} > 50\,\mathrm{GeV}$ - $m_\mathrm{T}^\mathrm{tot} = \sqrt{\left(p_\mathrm{T}^e+p_\mathrm{T}^\mu+E_\mathrm{T}^\mathrm{miss}\right)^2-\left(\vec{p}_\mathrm{T}^{\,e}+\vec{p}_\mathrm{T}^{\,\mu}+\vec{E}_\mathrm{T}^{\,\mathrm{miss}}\right)^2} < 45\,\mathrm{GeV}$ - $m_\mathrm{MMC} > 0\,\mathrm{GeV}$

Post-fit $m_\mathrm{MMC}$ distribution in the high-mass SR for the $m_A = 90\,\mathrm{GeV}$ signal mass hypothesis. $m_\mathrm{MMC}$ is the mass reconstructed by the Missing Mass Calculator. Processes contributing to the background Others are $Z/\gamma^* \rightarrow ee/\mu\mu$ and SM Higgs. The subscript on the $A\to\tau\tau$ process indicates the mass of the $A$ boson. otal includes all backgrounds and the signal process. The high-mass Signal Region is defined as: - 1 electron and 1 muon with opposite charge - $p_\mathrm{T}$ requirements of the leptons are a combination of the following: - $p_\mathrm{T}^e > 18\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 15\,\mathrm{GeV}$ or - $p_\mathrm{T}^e > 10\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 25\,\mathrm{GeV}$ or - $p_\mathrm{T}^e > 27\,\mathrm{GeV}$ and $p_\mathrm{T}^\mu > 10\,\mathrm{GeV}$ - $\vert \eta_e \vert < 2.47$, excluding $1.37 < \vert \eta_e \vert < 1.52$ - $\vert \eta_\mu \vert < 2.7$ - no jets with $b$-quarks - $\Delta R_{\ell\ell} < 1.0$ - $E_\mathrm{T}^\mathrm{miss} > 30\,\mathrm{GeV}$ - $m_\mathrm{T}^\mathrm{tot} = \sqrt{\left(p_\mathrm{T}^e+p_\mathrm{T}^\mu+E_\mathrm{T}^\mathrm{miss}\right)^2-\left(\vec{p}_\mathrm{T}^{\,e}+\vec{p}_\mathrm{T}^{\,\mu}+\vec{E}_\mathrm{T}^{\,\mathrm{miss}}\right)^2} < 65\,\mathrm{GeV}$ - $35\,\mathrm{GeV} < m_\mathrm{MMC} < 130\,\mathrm{GeV}$

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Search for supersymmetry using vector boson fusion signatures and missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 12 (2024) 116, 2024.
Inspire Record 2835159 DOI 10.17182/hepdata.156776

This paper presents a search for supersymmetric particles in models with highly compressed mass spectra, in events consistent with being produced through vector boson fusion. The search uses 140 fb$^{-1}$ of proton-proton collision data at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider. Events containing at least two jets with a large gap in pseudorapidity, large missing transverse momentum, and no reconstructed leptons are selected. A boosted decision tree is used to separate events consistent with the production of supersymmetric particles from those due to Standard Model backgrounds. The data are found to be consistent with Standard Model predictions. The results are interpreted using simplified models of $R$-parity-conserving supersymmetry in which the lightest supersymmetric partner is a bino-like neutralino with a mass similar to that of the lightest chargino and second-to-lightest neutralino, both of which are wino-like. Lower limits at 95% confidence level on the masses of next-to-lightest supersymmetric partners in this simplified model are established between 117 and 120 GeV when the lightest supersymmetric partners are within 1 GeV in mass.

12 data tables

Observed and predicted background distributions of the BDT score in $\text{SR}_\text{2j}$ after the exclusion fit. The nominal, pre-fit prediction of an example benchmark signal with $(m(\widetilde{\chi}_{2}^{0}/\widetilde{\chi}_{1}^{\pm}), \widetilde{\chi}_{1}^{0}) = (100, 99)$ GeV is shown in red. The 'Other' category contains rare backgrounds from diboson, triboson and top-quark production processes. The hatched band represents the post-fit experimental, theoretical, and statistical uncertainties in the total background. The bottom panel of each plot shows the ratio between the data and the post-fit background prediction.

Observed and predicted background distributions of the BDT score in $\text{SR}_{\geq3\text{j}}$ after the exclusion fit. The nominal, pre-fit prediction of an example benchmark signal with $(m(\widetilde{\chi}_{2}^{0}/\widetilde{\chi}_{1}^{\pm}), \widetilde{\chi}_{1}^{0}) = (100, 99)$ GeV is shown in red. The 'Other' category contains rare backgrounds from diboson, triboson and top-quark production processes. The hatched band represents the post-fit experimental, theoretical, and statistical uncertainties in the total background. The bottom panel of each plot shows the ratio between the data and the post-fit background prediction.

Expected (dashed black line) and observed (solid red line) 95% CL exclusion limits on the compressed SUSY simplified model with a bino-like LSP and wino-like NLSPs being considered. These are shown with $\pm1\sigma_\text{exp}$ (yellow band) from experimental systematic and statistical uncertainties, and with $\pm1\sigma^{\text{SUSY}}_{\text{theory}}$ (red dotted lines) from signal cross-section uncertainties, respectively. The limits set by the ATLAS searches using the soft lepton signature is illustrated by the blue region while the limit imposed by the LEP experiments is shown in grey.

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Search for same-charge top-quark pair production in $pp$ collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 02 (2025) 084, 2025.
Inspire Record 2832100 DOI 10.17182/hepdata.155341

A search for the production of top-quark pairs with the same electric charge ($tt$ or $\bar{t}\bar{t}$) is presented. The analysis uses proton-proton collision data at $\sqrt{s}=13$ TeV, recorded by the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 140 fb$^{-1}$. Events with two same-charge leptons and at least two $b$-tagged jets are selected. Neural networks are employed to define two selections sensitive to additional couplings beyond the Standard Model that would enhance the production rate of same-sign top-quark pairs. No significant signal is observed, leading to an upper limit on the total production cross-section of same-sign top-quark pairs of 1.6 fb at 95$\%$ confidence level. Corresponding limits on the three Wilson coefficients associated with the ${\cal O}_{tu}^{(1)}$, ${\cal O}_{Qu}^{(1)}$, and ${\cal O}_{Qu}^{(8)}$ operators in the Standard Model Effective Field Theory framework are derived.

15 data tables

Distributions of the $\mathrm{NN^{SvsB}}$ output for data and the expected background after the likelihood fit in the $SR_{ctu ++}$ signal region. The post-fit background expectations are shown as filled histograms, the combined pre-fit background expectations are shown as dashed lines. The signal distribution using the Wilson coefficient values $c_{tu}^{(1)}=0.04$, $c_{Qu}^{(1)}=0.1$, $c_{Qu}^{(8)}=0.1$ is shown with a dotted line, normalized to the same number of events as the background.

Distributions of the $\mathrm{NN^{SvsB}}$ output for data and the expected background after the likelihood fit in the $SR_{ctu --}$ signal region. The post-fit background expectations are shown as filled histograms, the combined pre-fit background expectations are shown as dashed lines. The signal distribution using the Wilson coefficient values $c_{tu}^{(1)}=0.04$, $c_{Qu}^{(1)}=0.1$, $c_{Qu}^{(8)}=0.1$ is shown with a dotted line, normalized to the same number of events as the background.

Distributions of the $\mathrm{NN^{SvsB}}$ output for data and the expected background after the likelihood fit in the $SR_{cQu ++}$ signal region. The post-fit background expectations are shown as filled histograms, the combined pre-fit background expectations are shown as dashed lines. The signal distribution using the Wilson coefficient values $c_{tu}^{(1)}=0.04$, $c_{Qu}^{(1)}=0.1$, $c_{Qu}^{(8)}=0.1$ is shown with a dotted line, normalized to the same number of events as the background.

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Search for $t\bar{t}H/A \rightarrow t\bar{t}t\bar{t}$ production in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
Eur.Phys.J.C 85 (2025) 573, 2025.
Inspire Record 2823281 DOI 10.17182/hepdata.158356

A search is presented for a heavy scalar ($H$) or pseudo-scalar ($A$) predicted by the two-Higgs-doublet models, where the $H/A$ is produced in association with a top-quark pair ($t\bar{t}H/A$), and with the $H/A$ decaying into a $t\bar{t}$ pair. Events are selected requiring exactly one or two opposite-charge electrons or muons. Data-driven corrections are applied to improve the modelling of the $t\bar{t}$+jets background in the regime with high jet and $b$-jet multiplicities. These include a novel multi-dimensional kinematic reweighting based on a neural network trained using data and simulations. An $H/A$-mass parameterised graph neural network is trained to optimise the signal-to-background discrimination. In combination with the previous search performed by the ATLAS Collaboration in the multilepton final state, the observed upper limits on the $t\bar{t}H/A \rightarrow t\bar{t}t\bar{t}$ production cross-section at 95% confidence level range between 14 fb and 5.0 fb for an $H/A$ with mass between 400 GeV and 1000 GeV, respectively. Assuming that both the $H$ and $A$ contribute to the $t\bar{t}t\bar{t}$ cross-section, $\tan\beta$ values below 1.7 or 0.7 are excluded for a mass of 400 GeV or 1000 GeV, respectively. The results are also used to constrain a model predicting the pair production of a colour-octet scalar, with the scalar decaying into a $t\bar{t}$ pair.

23 data tables

Post-fit distribution of the GNN score evaluated with $m_{H/A}$ = 400 GeV in the 1L region with $\geq 10$ jets and four $b$-tagged jets. The fit is performed under the background-only hypothesis.

Post-fit distribution of the GNN score evaluated with $m_{H/A}$ = 400 GeV in the 2LOS region with $\geq8$ jets and $\geq 4$ $𝑏$-tagged jets. The fit is performed under the background-only hypothesis.

Post-fit distribution of the GNN score evaluated with $m_{H/A}$ = 400 GeV in the validation region in the 1L region with $\geq 10$ jets. These regions do not enter the fit. The post-fit background prediction is obtained using the post-fit nuisance parameters from the background-only fit in the control and signal regions.

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Search for boosted low-mass resonances decaying into hadrons produced in association with a photon in pp collisions at $\sqrt{s}=$13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 01 (2025) 099, 2025.
Inspire Record 2813982 DOI 10.17182/hepdata.153849

Many extensions of the Standard Model, including those with dark matter particles, propose new mediator particles that decay into hadrons. This paper presents a search for such low mass narrow resonances decaying into hadrons using 140 fb$^{-1}$ of proton-proton collision data recorded with the ATLAS detector at a centre-of-mass energy of 13 TeV. The resonances are searched for in the invariant mass spectrum of large-radius jets with two-pronged substructure that are recoiling against an energetic photon from initial state radiation, which is used as a trigger to circumvent limitations on the maximum data recording rate. This technique enables the search for boosted hadronically decaying resonances in the mass range 20-100 GeV hitherto unprobed by the ATLAS Collaboration. The observed data are found to agree with Standard Model predictions and 95% confidence level upper limits are set on the coupling of a hypothetical new spin-1 $Z'$ resonance with Standard Model quarks as a function of the assumed $Z'$-boson mass in the range between 20 and 200 GeV.

6 data tables

Invariant mass $m_{J}$ of the resonance candidates in the region defined with central photon $\eta_{\gamma} < 1.3$ and a tagged large-$R$ jet after the fit to data under the background-only hypothesis. The total systematic uncertainty is shown as the hatched band. Three representative $Z^{`}$ signal distributions are overlaid as red lines. The signal is shown for $g_q=0.2$ with production cross sections of 309 fb, 143 fb, and 34.2 fb for $m_{Z^{`}}=(20,~50,~\text{and}~125~\text{GeV}$), respectively.

Invariant mass $m_{J}$ of the resonance candidates in the region defined with forward photon $\eta_{\gamma} > 1.3$ and a tagged large-$R$ jet after the fit to data under the background-only hypothesis. The total systematic uncertainty is shown as the hatched band. Three representative $Z^{`}$ signal distributions are overlaid as red lines. The signal is shown for $g_q=0.2$ with production cross sections of 309 fb, 143 fb, and 34.2 fb for $m_{Z^{`}}=(20,~50,~\text{and}~125~\text{GeV}$), respectively.

Invariant mass $m_{J}$ of the resonance candidates in the region defined with central photon $\eta_{\gamma} < 1.3$ and an anti-tagged large-$R$ jetafter the fit to data under the background-only hypothesis. The total systematic uncertainty is shown as the hatched band. Three representative $Z^{`}$ signal distributions are overlaid as red lines. The signal is shown for $g_q=0.2$ with production cross sections of 309 fb, 143 fb, and 34.2 fb for $m_{Z^{`}}=(20,~50,~\text{and}~125~\text{GeV}$), respectively.

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Differential cross-section measurements of Higgs boson production in the $H\to\tau^+\tau^-$ decay channel in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Aakvaag, Erlend ; Abbott, Braden Keim ; et al.
JHEP 03 (2025) 010, 2025.
Inspire Record 2810563 DOI 10.17182/hepdata.157351

Differential measurements of Higgs boson production in the $\tau$-lepton-pair decay channel are presented in the gluon fusion, vector-boson fusion (VBF), $VH$ and $t\bar{t}H$ associated production modes, with particular focus on the VBF production mode. The data used to perform the measurements correspond to 140 fb$^{-1}$ of proton-proton collisions collected by the ATLAS experiment at the LHC. Two methods are used to perform the measurements: the Simplified Template Cross-Section (STXS) approach and an Unfolded Fiducial Differential measurement considering only the VBF phase space. For the STXS measurement, events are categorized by their production mode and kinematic properties such as the Higgs boson's transverse momentum ($p^{\text{H}}_\text{T}$), the number of jets produced in association with the Higgs boson, or the invariant mass of the two leading jets ($m_{jj}$). For the VBF production mode, the ratio of the measured cross-section to the Standard Model prediction for $m_{jj}>1.5$ TeV and $p^{\text{H}}_\text{T}>200$ GeV ($p^{\text{H}}_\text{T}<200$ GeV) is ${1.29}^{+0.39}_{-0.34}$ (${0.12}^{+0.34}_{-0.33}$). This is the first VBF measurement for the higher-$p^{\text{H}}_\text{T}$ criteria, and the most precise for the lower-$p^{\text{H}}_\text{T}$ criteria. The fiducial cross-section measurements, which only consider the kinematic properties of the event, are performed as functions of variables characterizing the VBF topology, such as the signed $\Delta\phi_{jj}$ between the two leading jets. The measurements have a precision of 30%-50% and agree well with the Standard Model predictions. These results are interpreted in the SMEFT framework, and place the strongest constraints to date on the CP-odd Wilson coefficient $c_{H\tilde{W}}$.

32 data tables

Distribution of the reconstructed $\tau\tau$ invariant mass ($m_{\tau\tau}$) for all events in the VBF_0 signal region for $p_{\text{T}}^{H}<200$ GeV. The observed Higgs boson signal corresponds to $(\sigma\times B)/(\sigma\times B)_{\text{SM}}\,=\,0.99$. Entries with values above the $x$-axis range are shown in the last bin of each distribution. The prediction for each sample is determined from the likelihood fit performed to measure the total $pp\rightarrow H\rightarrow\tau\tau$ cross-section.

Distribution of the reconstructed $\tau\tau$ invariant mass ($m_{\tau\tau}$) for all events in the VBF_0 signal region for $p_{\text{T}}^{H}>200$ GeV. The observed Higgs boson signal corresponds to $(\sigma\times B)/(\sigma\times B)_{\text{SM}}\,=\,0.99$. Entries with values above the $x$-axis range are shown in the last bin of each distribution. The prediction for each sample is determined from the likelihood fit performed to measure the total $pp\rightarrow H\rightarrow\tau\tau$ cross-section.

Distribution of the reconstructed $\tau\tau$ invariant mass ($m_{\tau\tau}$) for all events in the VBF_1 signal region for $p_{\text{T}}^{H}<200$ GeV. The observed Higgs boson signal corresponds to $(\sigma\times B)/(\sigma\times B)_{\text{SM}}\,=\,0.99$. Entries with values above the $x$-axis range are shown in the last bin of each distribution. The prediction for each sample is determined from the likelihood fit performed to measure the total $pp\rightarrow H\rightarrow\tau\tau$ cross-section.

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