We present a measurement of the $W$ boson production charge asymmetry in $p\bar{p}\rightarrow W+X \rightarrow e\nu +X$ events at a center of mass energy of 1.96 TeV, using 9.7 fb$^{-1}$ of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider. The neutrino longitudinal momentum is determined using a neutrino weighting method, and the asymmetry is measured as a function of the $W$ boson rapidity. The measurement extends over wider electron pseudorapidity region than previous results, and is the most precise to date, allowing for precise determination of proton parton distribution functions in global fits.
${\it CP}$-folded $W$ charge asymmetry for data and predictions from MC@NLO using NNPDF2.3 PDFs tabulated in percent (%) for each $|y_W|$ bin. The $\langle|y_W|\rangle$ is calculated as the cross section weighted average of $y_W$ in each bin from RESBOS with photos. For data, the first uncertainty is statistical and the second is systematic. The uncertainties on the prediction come from both the PDF uncertainties and $\alpha_s$ uncertainties. The numbers in this table are the revised data published on 10th December 2014 (after the journal publication).
Correlation coefficients between central values of asymmetry in different $|y_W|$ bins.
We present a measurement of the muon charge asymmetry from the decay of the $W$ boson via W to mu nu using 7.3 fb^{-1} of integrated luminosity collected with the D0 detector at the Fermilab Tevatron Collider at sqrt{s} = 1.96 TeV. The muon charge asymmetry is presented in two kinematic regions in muon transverse momentum and event missing transverse energy: (p^{\mu}_{T} > 25 GeV, \met > 25 GeV) and (p^{\mu}_{T} > 35 GeV, \met > 35 GeV). The measured asymmetries are compared with theory predictions made using three parton distribution function sets. The predictions do not describe the data well for p^{\mu}_{T} > 35 GeV, \met > 35 GeV, and larger values of muon pseudorapidity.
Muon charge asymmetry for data and predictions from RESBOS+PHOTOS using the CTEQ6.6 PDFs. The measurement is shown with statistical uncertainties followed by systematic uncertainties. The uncertainties for the predictions are only from the PDFs.
Muon charge asymmetry for data and predictions from RESBOS+PHOTOS using the CTEQ6.6 PDFs. The measurement is shown with statistical uncertainties followed by systematic uncertainties. The uncertainties for the predictions are only from the PDFs.
Contributions from individual sources of systematic uncertainty for the ($p^{\mu}_{T} > 25$, $E_T^{missing} > 25$) GeV kinematic region. All uncertainty values are multiplied by 100. The columns (1-7) correspond to: 1.0 = Electro-Weak background 2.0 = Multi-Jet background 3.0 = Charge mis-identification 4.0 = Relative charge efficiency 5.0 = Magnet polarity weighting 6.0 = Momentum/$E_T^{missing}$ resolution 7.0 = Trigger isolation.
Samples of inclusive photon+2 jet and photon+3 jet events collected by the D0 experiment with an integrated luminosity of about 1fb^-1 in ppbar collisions at sqrt{s}=1.96 TeV are used to measure cross sections as a function of the angle in the plane transverse to the beam direction between the transverse momentum (pT) of the photon+leading jet system (jets are ordered in pT) and pT of the other jet for photon+2 jet, or pT sum of the two other jets for photon+3 jet events. The results are compared to different models of multiple parton interactions (MPI) in the PYTHIA and SHERPA Monte Carlo (MC) generators. The data indicate a contribution from events with double parton (DP) interactions and are well described by predictions provided by the PYTHIA MPI models with pT-ordered showers and by SHERPA with the default MPI model. The photon+2 jet data are also used to determine the fraction of events with DP interactions as a function of the azimuthal angle and as a function of the second jet pT.
The normalised differential cross section of the azmiuthal decorrelation variable DELTA for the GAMMA+3JET sample for the PT of the second jet in the range 15 TO 30 GeV.
The normalised differential cross section of the azmiuthal decorrelation variable DELTA for the GAMMA+2JET sample for the PT of the second jet in the range 15 TO 20 GeV.
The normalised differential cross section of the azmiuthal decorrelation variable DELTA for the GAMMA+2JET sample for the PT of the second jet in the range 20 TO 25 GeV.
First measurements of the W -> lnu and Z/gamma* -> ll (l = e, mu) production cross sections in proton-proton collisions at sqrt(s) = 7 TeV are presented using data recorded by the ATLAS experiment at the LHC. The results are based on 2250 W -> lnu and 179 Z/gamma* -> ll candidate events selected from a data set corresponding to an integrated luminosity of approximately 320 nb-1. The measured total W and Z/gamma*-boson production cross sections times the respective leptonic branching ratios for the combined electron and muon channels are $\stotW$ * BR(W -> lnu) = 9.96 +- 0.23(stat) +- 0.50(syst) +- 1.10(lumi) nb and $\stotZg$ * BR(Z/gamma* -> ll) = 0.82 +- 0.06(stat) +- 0.05(syst) +- 0.09(lumi) nb (within the invariant mass window 66 < m_ll < 116 GeV). The W/Z cross-section ratio is measured to be 11.7 +- 0.9(stat) +- 0.4(syst). In addition, measurements of the W+ and W- production cross sections and of the lepton charge asymmetry are reported. Theoretical predictions based on NNLO QCD calculations are found to agree with the measurements.
Measured fiducial cross section times leptonic branching ratio for W+ production in the W+ -> e+ nu final state.
Measured fiducial cross section times leptonic branching ratio for W- production in the W- -> e- nubar final state.
Measured fiducial cross section times leptonic branching ratio for W+/- production in the combined W+ -> e+ nu and W- -> e- nubar final state.
Dijet angular distributions from the first LHC pp collisions at center-of-mass energy sqrt(s) = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb-1. Dijet $\chi$ distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the $\chi$ distributions excludes quark contact interactions with a compositeness scale $\Lambda$ below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits.
CHI distribution for mass bin 340 to 520 GeV.
CHI distribution for mass bin 520 to 800 GeV.
CHI distribution for mass bin 800 to 1200 GeV.
A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the Large Hadron Collider (LHC) and correspond to an integrated luminosity of 315 nb^-1 collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section and signal acceptance for excited-quark (q*) production as a function of q* mass. These exclude at the 95% CL the q* mass interval 0.30 < mq* < 1.26 TeV, extending the reach of previous experiments.
The dijet mass distribution (NUMBER OF EVENTS).
95 PCT CL upper limit of the cross section x acceptance.
Several extensions of the Standard Model predict the production of dark matter particles at the LHC. A search for dark matter particles produced in association with a dark Higgs boson decaying into $W^{+}W^{-}$ in the $\ell^\pm\nu q \bar q'$ final states with $\ell=e,\mu$ is presented. This analysis uses 139 fb$^{-1}$ of $pp$ collisions recorded by the ATLAS detector at a centre-of-mass energy of 13 TeV. The $W^\pm \to q\bar q'$ decays are reconstructed from pairs of calorimeter-measured jets or from track-assisted reclustered jets, a technique aimed at resolving the dense topology from a pair of boosted quarks using jets in the calorimeter and tracking information. The observed data are found to agree with Standard Model predictions. Scenarios with dark Higgs boson masses ranging between 140 and 390 GeV are excluded.
Probability of finding at least one TAR jet, where the p<sub>T</sub>-leading TAR jet passes the m<sub>Wcand</sub> and D<sub>2</sub><sup>β=1</sup> requirements, as a function of m<sub>s</sub>. The probability is determined in a sample of signal events with m<sub>Z'</sub>=500 GeV, with the preselections applied.
Probability of finding at least one TAR jet, where the p<sub>T</sub>-leading TAR jet passes the m<sub>Wcand</sub> and D<sub>2</sub><sup>β=1</sup> requirements, as a function of m<sub>s</sub>. The probability is determined in a sample of signal events with m<sub>Z'</sub>=1000 GeV, with the preselections applied.
Probability of finding at least one TAR jet, where the p<sub>T</sub>-leading TAR jet passes the m<sub>Wcand</sub> and D<sub>2</sub><sup>β=1</sup> requirements, as a function of m<sub>s</sub>. The probability is determined in a sample of signal events with m<sub>Z'</sub>=1700 GeV, with the preselections applied.
A measurement of the splitting scales occuring in the $k_\mathrm{t}$ jet-clustering algorithm is presented for final states containing a $Z$ boson. The measurement is done using 20.2 fb$^{-1}$ of proton-proton collision data collected at a centre-of-mass energy of $\sqrt{s} = 8$ TeV by the ATLAS experiment at the LHC in 2012. The measurement is based on charged-particle track information, which is measured with excellent precision in the $p_\mathrm{T}$ region relevant for the transition between the perturbative and the non-perturbative regimes. The data distributions are corrected for detector effects, and are found to deviate from state-of-the-art predictions in various regions of the observables.
The measured fiducial as a function of sqrt(d0). The fiducial cross sections are measred for the charged-only particle level in the muon channel as well as the electron channel. Extrapolations to the complete fiducial phase space including charged and neutral particles are also shown for the muon channel and the electron channel.
The measured fiducial as a function of sqrt(d1). The fiducial cross sections are measred for the charged-only particle level in the muon channel as well as the electron channel. Extrapolations to the complete fiducial phase space including charged and neutral particles are also shown for the muon channel and the electron channel.
The measured fiducial as a function of sqrt(d2). The fiducial cross sections are measred for the charged-only particle level in the muon channel as well as the electron channel. Extrapolations to the complete fiducial phase space including charged and neutral particles are also shown for the muon channel and the electron channel.
Inclusive jet production cross-sections are measured in proton--proton collisions at a centre-of-mass energy of $\sqrt{s}=$8 TeV recorded by the ATLAS experiment at the Large Hadron Collider at CERN. The total integrated luminosity of the analysed data set amounts to $20.2$ fb$^{-1}$. Double-differential cross-sections are measured for jets defined by the anti-$k_{t}$ jet clustering algorithm with radius parameters of $R=0.4$ and $R=0.6$ and are presented as a function of the jet transverse momentum, in the range between 70 GeV and 2.5 TeV and in six bins of the absolute jet rapidity, between 0 and 3.0. The measured cross-sections are compared to predictions of quantum chromodynamics, calculated at next-to-leading order in perturbation theory, and corrected for non-perturbative and electroweak effects. The level of agreement with predictions, using a selection of different parton distribution functions for the proton, is quantified. Tensions between the data and the theory predictions are observed.
rapidity bin 0 < |Y| < 0.5 anti-kt R=0.6
rapidity bin 0.5 < |Y| < 1.0 anti-kt R=0.6
rapidity bin 1.0 < |Y| < 1.5 anti-kt R=0.6
A search for doubly charged Higgs bosons with pairs of prompt, isolated, highly energetic leptons with the same electric charge is presented. The search uses a proton-proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to 36.1 $\mathrm{fb}^{-1}$ of integrated luminosity recorded in 2015 and 2016 by the ATLAS detector at the LHC. This analysis focuses on the decays $H^{\pm\pm}\rightarrow e^{\pm}e^{\pm}$, $H^{\pm\pm}\rightarrow e^{\pm}\mu^{\pm}$ and $H^{\pm\pm}\rightarrow \mu^{\pm}\mu^{\pm}$, fitting the dilepton mass spectra in several exclusive signal regions. No significant evidence of a signal is observed and corresponding limits on the production cross-section are derived at 95% confidence level. The observed lower limit on the mass of a doubly charged Higgs boson only coupling to left-handed leptons ($e$,$\mu$) varies from 770 GeV to 870 GeV (850 GeV expected) for $B(H^{\pm\pm}\rightarrow \ell^{\pm}\ell^{\pm})$ = 100% and both the expected and observed mass limits are above 450 GeV for $B(H^{\pm\pm}\rightarrow \ell^{\pm}\ell^{\pm})$ = 10% and any combination of partial branching ratios.
Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 100\%$, $B(e \mu ) = 0\%$, and $B( \mu \mu ) = 0\%$.
Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 0\%$, $B(e \mu ) = 0\%$, and $B( \mu \mu ) = 100\%$.
Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 0\%$, $B(e \mu ) = 100\%$, and $B( \mu \mu ) = 0\%$.
A measurement of the production cross section for two isolated photons in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=8$ TeV is presented. The results are based on an integrated luminosity of 20.2 fb$^{-1}$ recorded by the ATLAS detector at the Large Hadron Collider. The measurement considers photons with pseudorapidities satisfying $|\eta^{\gamma}|<1.37$ or ${1.56<|\eta^{\gamma}|<2.37}$ and transverse energies of respectively $E_{\mathrm{T,1}}^{\gamma}>40$ GeV and $E_{\mathrm{T,2}}^{\gamma}>30$ GeV for the two leading photons ordered in transverse energy produced in the interaction.The background due to hadronic jets and electrons is subtracted using data-driven techniques. The fiducial cross sections are corrected for detector effects and measured differentially as a function of six kinematic observables. The measured cross section integrated within the fiducial volume is $16.8 \pm 0.8$ pb. The data are compared to fixed-order QCD calculations at next-to-leading-order and next-to-next-to-leading-order accuracy as well as next-to-leading-order computations including resummation of initial-state gluon radiation at next-to-next-to-leading logarithm or matched to a parton shower, with relative uncertainties varying from 5% to 20%.
The measured fiducial (total xs).
The measured differential as a function of Mgg.
The measured differential as a function of pTgg.
The production of a $Z$ boson and a photon in association with a high-mass dijet system is studied using 20.2fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of $\sqrt{s}$ = 8 TeV recorded with the ATLAS detector in 2012 at the Large Hadron Collider. Final states with a photon and a Z boson decaying into a pair of either electrons, muons, or neutrinos are analysed. Electroweak and total $pp \to Z\gamma j j$ cross-sections are extracted in two fiducial regions with different sensitivities to electroweak production processes. Quartic couplings of vector bosons are studied in regions of phase space with an enhanced contribution from pure electroweak production, sensitive to vector-boson scattering processes $VV \to Z\gamma$. No deviations from Standard Model predictions are observed and constraints are placed on anomalous couplings parameterized by higher-dimensional operators using effective field theory.
The measured fiducial sections of Zyjj in the charged-leptonic channel. In the measured cross-sections, the first uncertainty is the statistical uncertainty, and the second one is the combined systematic uncertainty.
95% confidence level cross-section upper limits on the $Z\gamma jj$ processes in both charged-leptonic and neutrino channels. The reconstruction efficiencies are provided as C-factors.
95% confidence level interval (expected and observed) on aQGC parameters (VBFNLO formalism) provided for different values of unitarity scale (Form Factor).
Results of a search for physics beyond the Standard Model in events containing an energetic photon and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. As the number of events observed in data, corresponding to an integrated luminosity of 36.1 $\textrm fb^{-1}$ of proton-proton collisions at a centre-of-mass energy of 13 TeV, is in agreement with the Standard Model expectations, exclusion limits in models where dark-matter candidates are pair-produced are determined. For dark-matter production via an axial-vector or a vector mediator in the s-channel, this search excludes mediator masses below 750-1200 GeV for dark-matter candidate masses below 230-480 GeV at 95% confidence level, depending on the couplings. In an effective theory of dark-matter production, the limits restrict the value of the suppression scale $M_{*}$ to be above 790 GeV at 95% confidence level. A limit is also reported on the production of a high-mass scalar resonance by processes beyond the Standard Model, in which the resonance decays to $Z\gamma$ and the Z boson subsequently decays into neutrinos.
Observed event yields in 36.1 fb$^{-1}$ of data compared to expected yields from SM backgrounds in all signal regions, as predicted from the simultaneous fit to their respective CRs. The first three lines report the yields obtained from the inclusive-SR fit, while the two last lines report the yields obtained from the multiple-bin fit. The uncertainty includes both the statistical and systematic uncertainties.
The observed 95% CL exclusion contour for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.
The expected 95% CL exclusion contour (+1$\sigma$) for a simplified model of dark-matter production involving an axial-vector operator, Dirac DM and couplings $g_{q}$ = 0.25, $g_{\chi}$ = 1 and $g_{l}$ = 0 as a function of the dark-matter mass $m_{\chi}$ and the mediator mass $m_{\mathrm{med}}$. The plane under the limit curve is excluded.
A search for an invisibly decaying Higgs boson or dark matter candidates produced in association with a leptonically decaying $Z$ boson in proton--proton collisions at $\sqrt{s} =$ 13 TeV is presented. This search uses 36.1 fb$^{-1}$ of data collected by the ATLAS experiment at the Large Hadron Collider. No significant deviation from the expectation of the Standard Model backgrounds is observed. Assuming the Standard Model $ZH$ production cross-section, an observed (expected) upper limit of 67% (39%) at the 95% confidence level is set on the branching ratio of invisible decays of the Higgs boson with mass $m_H = $ 125 GeV. The corresponding limits on the production cross-section of the $ZH$ process with the invisible Higgs boson decays are also presented. Furthermore, exclusion limits on the dark matter candidate and mediator masses are reported in the framework of simplified dark matter models.
Observed E<sub>T</sub><sup>miss</sup> distribution in the ee channel compared to the signal and background predictions. The error band shows the total statistical and systematic uncertainty on the background prediction. The background predictions are presented as they are before being fit to the data. The ratio plot gives the observed data yield over the background prediction (black points) as well as the signal-plus-background contribution divided by the background prediction (blue or purple line) in each E<sub>T</sub><sup>miss</sup> bin. The rightmost bin contains the overflow contributions. The ZH → ℓℓ + inv signal distribution is shown with BR<sub>H → inv</sub> =0.3, which is the value most compatible with data. The simulated DM distribution with m<sub>med</sub> = 500 GeV and m<sub>χ</sub> = 100 GeV is also scaled (with a factor of 0.27) to the best-fit contribution.
Observed E<sub>T</sub><sup>miss</sup> distribution in the μμ channel compared to the signal and background predictions. The error band shows the total statistical and systematic uncertainty on the background prediction. The background predictions are presented as they are before being fit to the data. The ratio plot gives the observed data yield over the background prediction (black points) as well as the signal-plus-background contribution divided by the background prediction (blue or purple line) in each E<sub>T</sub><sup>miss</sup> bin. The rightmost bin contains the overflow contributions. The ZH → ℓℓ + inv signal distribution is shown with BR<sub>H → inv</sub> =0.3, which is the value most compatible with data. The simulated DM distribution with m<sub>med</sub> = 500 GeV and m<sub>χ</sub> = 100 GeV is also scaled (with a factor of 0.27) to the best-fit contribution.
DM exclusion limit in the two-dimensional phase space of WIMP mass m<sub>χ</sub> vs mediator mass m<sub>med</sub> determined using the combined ee+μμ channel. Both the observed and expected limits are presented, and the 1σ uncertainty band for the expected limits is also provided. Regions bounded by the limit curves are excluded at the 95% CL. The grey line labelled with "m<sub>med</sub> = 2m<sub>χ</sub>'' indicates the kinematic threshold where the mediator can decay on-shell into WIMPs, and the other grey line gives the perturbative limit (arXiv 1603.04156). The relic density line (arXiv 1603.04156) illustrates the combination of m<sub>χ</sub> and m<sub>med</sub> that would explain the observed DM relic density.
The inclusive and fiducial $t\bar{t}$ production cross-sections are measured in the lepton+jets channel using 20.2 fb$^{-1}$ of proton-proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. Major systematic uncertainties due to the modelling of the jet energy scale and $b$-tagging efficiency are constrained by separating selected events into three disjoint regions. In order to reduce systematic uncertainties in the most important background, the W+jets process is modelled using Z+jets events in a data-driven approach. The inclusive $t\bar{t}$ cross-section is measured with a precision of 5.7% to be $\sigma_{\text{inc}}(t\bar{t})$ = 248.3 $\pm$ 0.7 (stat.) $\pm$ 13.4 (syst.) $\pm$ 4.7 (lumi.) pb, assuming a top-quark mass of 172.5 GeV. The result is in agreement with the Standard Model prediction. The cross-section is also measured in a phase space close to that of the selected data. The fiducial cross-section is $\sigma_{\text{fid}}(t\bar{t})$ = 48.8 $\pm$ 0.1 (stat.) $\pm$ 2.0 (syst.) $\pm$ 0.9 (lumi.) pb with a precision of 4.5%.
The measured inclusive cross section. The first systematic uncertainty (sys_1) is the combined systematic uncertainty excluding luminosity, the second (sys_2) is the luminosity
The measured fiducial cross section. The first systematic uncertainty (sys_1) is the combined systematic uncertainty excluding luminosity, the second (sys_2) is the luminosity
Measurements of differential cross-sections of top-quark pair production in fiducial phase-spaces are presented as a function of top-quark and $t\bar{t}$ system kinematic observables in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$=13 TeV. The data set corresponds to an integrated luminosity of $3.2$ fb${}^{-1}$, recorded in 2015 with the ATLAS detector at the CERN Large Hadron Collider. Events with exactly one electron or muon and at least two jets in the final state are used for the measurement. Two separate selections are applied that each focus on different top-quark momentum regions, referred to as resolved and boosted topologies of the $t\bar{t}$ final state. The measured spectra are corrected for detector effects and are compared to several Monte Carlo simulations by means of calculated $\chi^2$ and $p$-values.
Covariance matrix of the absolute cross-section as function of the top quark pT, accounting for the statistical and systematic uncertainties in the resolved topology.
Covariance matrix of the absolute cross-section as function of the top quark pT, accounting for the statistical and systematic uncertainties in the resolved topology.
Covariance matrix of the relative cross-section as function of the top quark pT, accounting for the statistical and systematic uncertainties in the resolved topology.
A search for $W'$-boson production in the $W' \rightarrow t\bar{b} \rightarrow q\bar{q}' b\bar{b}$ decay channel is presented using 36.1 fb$^{-1}$ of 13 TeV proton-proton collision data collected by the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search is interpreted in terms of both a left-handed and a right-handed chiral $W'$ boson within the mass range 1-5 TeV. Identification of the hadronically decaying top quark is performed using jet substructure tagging techniques based on a shower deconstruction algorithm. No significant deviation from the Standard Model prediction is observed and the results are expressed as upper limits on the $W' \rightarrow t\bar{b}$ production cross-section times branching ratio as a function of the $W'$-boson mass. These limits exclude $W'$ bosons with right-handed couplings with masses below 3.0 TeV and $W'$ bosons with left-handed couplings with masses below 2.9 TeV, at the 95% confidence level.
Observed and expected 95% CL limits on the right-handed W'-boson cross-section times branching ratio of W' to tb decay as a function of the corresponding W'-boson mass.
Observed and expected 95% CL limits on the left-handed W'-boson cross-section times branching ratio of W' to tb decay as a function of the corresponding W'-boson mass.
Reconstructed mtb distribution in data and for the background after the fit to the data in the signal region SR1. The statistical uncertainty on data points is calculated using assymetric Poisson confidence intervals.
A search for the supersymmetric partners of the Standard Model bottom and top quarks is presented. The search uses 36.1 fb$^{-1}$ of $pp$ collision data at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider. Direct production of pairs of bottom and top squarks ($\tilde{b}_{1}$ and $\tilde{t}_{1}$) is searched for in final states with $b$-tagged jets and missing transverse momentum. Distinctive selections are defined with either no charged leptons (electrons or muons) in the final state, or one charged lepton. The zero-lepton selection targets models in which the $\tilde{b}_{1}$ is the lightest squark and decays via $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$, where $\tilde{\chi}^{0}_{1}$ is the lightest neutralino. The one-lepton final state targets models where bottom or top squarks are produced and can decay into multiple channels, $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$ and $\tilde{b}_{1} \rightarrow t \tilde{\chi}^{\pm}_{1}$, or $\tilde{t}_{1} \rightarrow t \tilde{\chi}^{0}_{1}$ and $\tilde{t}_{1} \rightarrow b \tilde{\chi}^{\pm}_{1}$, where $\tilde{\chi}^{\pm}_{1}$ is the lightest chargino and the mass difference $m_{\tilde{\chi}^{\pm}_{1}}- m_{\tilde{\chi}^{0}_{1}}$ is set to 1 GeV. No excess above the expected Standard Model background is observed. Exclusion limits at 95\% confidence level on the mass of third-generation squarks are derived in various supersymmetry-inspired simplified models.
- - - - - - - - - - - - - - - - - - - - <br/><b>Acceptance:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Acceptance1">b0L-SRA350</a> <a href="79165?version=1&table=Acceptance2">b0L-SRA450</a> <a href="79165?version=1&table=Acceptance3">b0L-SRA550</a> <a href="79165?version=1&table=Acceptance4">b0L-SRB</a> <a href="79165?version=1&table=Acceptance5">b0L-SRC</a> <a href="79165?version=1&table=Acceptance6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Acceptance7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Acceptance8">b1L-SRA450</a> <a href="79165?version=1&table=Acceptance9">b1L-SRA600</a> <a href="79165?version=1&table=Acceptance10">b1L-SRA750</a> <a href="79165?version=1&table=Acceptance11">b1L-SRB</a> <a href="79165?version=1&table=Acceptance12">b1L-best</a><br/><br/><b>Efficiency:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Efficiency1">b0L-SRA350</a> <a href="79165?version=1&table=Efficiency2">b0L-SRA450</a> <a href="79165?version=1&table=Efficiency3">b0L-SRA550</a> <a href="79165?version=1&table=Efficiency4">b0L-SRB</a> <a href="79165?version=1&table=Efficiency5">b0L-SRC</a> <a href="79165?version=1&table=Efficiency6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Efficiency7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Efficiency8">b1L-SRA450</a> <a href="79165?version=1&table=Efficiency9">b1L-SRA600</a> <a href="79165?version=1&table=Efficiency10">b1L-SRA750</a> <a href="79165?version=1&table=Efficiency11">b1L-SRB</a> <a href="79165?version=1&table=Efficiency12">b1L-best</a><br/><br/><b>Best SR Mapping:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=BestSR4">b0L</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=BestSR1">b1L</a> <a href="79165?version=1&table=BestSR2">b0L</a> <a href="79165?version=1&table=BestSR3">combined</a><br/><br/><b>Exclusion Contour:</b><br/><i>symmetric:</i> b0L-SRA350 <a href="79165?version=1&table=Contour1">exp</a> <a href="79165?version=1&table=Contour2">obs</a> b0L-SRA450 <a href="79165?version=1&table=Contour5">exp</a> <a href="79165?version=1&table=Contour6">obs</a> b0L-SRA550 <a href="79165?version=1&table=Contour9">exp</a> <a href="79165?version=1&table=Contour10">obs</a> b0L-SRB <a href="79165?version=1&table=Contour11">exp</a> <a href="79165?version=1&table=Contour12">obs</a> b0L-SRC <a href="79165?version=1&table=Contour15">exp</a> <a href="79165?version=1&table=Contour16">obs</a> b0L-best <a href="79165?version=1&table=Contour17">exp</a> <a href="79165?version=1&table=Contour18">obs</a><br/><i>asymmetric:</i> b0L-SRA350 <a href="79165?version=1&table=Contour3">exp</a> <a href="79165?version=1&table=Contour4">obs</a> b0L-SRA450 <a href="79165?version=1&table=Contour7">exp</a> <a href="79165?version=1&table=Contour8">obs</a> b0L-SRB <a href="79165?version=1&table=Contour13">exp</a> <a href="79165?version=1&table=Contour14">obs</a> b0L-best <a href="79165?version=1&table=Contour19">exp</a> <a href="79165?version=1&table=Contour20">obs</a> b1L-SRA300-2j <a href="79165?version=1&table=Contour21">exp</a> <a href="79165?version=1&table=Contour22">obs</a> b1L-SRA450 <a href="79165?version=1&table=Contour23">exp</a> <a href="79165?version=1&table=Contour24">obs</a> b1L-SRA600 <a href="79165?version=1&table=Contour25">exp</a> <a href="79165?version=1&table=Contour26">obs</a> b1L-SRA750 <a href="79165?version=1&table=Contour27">exp</a> <a href="79165?version=1&table=Contour28">obs</a> b1L-SRB <a href="79165?version=1&table=Contour29">exp</a> <a href="79165?version=1&table=Contour30">obs</a> b1L-best <a href="79165?version=1&table=Contour31">exp</a> <a href="79165?version=1&table=Contour32">obs</a> A-LowMass <a href="79165?version=1&table=Contour33">exp</a> <a href="79165?version=1&table=Contour34">obs</a> A-HighMass <a href="79165?version=1&table=Contour35">exp</a> <a href="79165?version=1&table=Contour36">obs</a> B combination <a href="79165?version=1&table=Contour37">exp</a> <a href="79165?version=1&table=Contour38">obs</a> Best combination <a href="79165?version=1&table=Contour39">exp</a> <a href="79165?version=1&table=Contour40">obs</a><br/><br/><b>SR Distribution:</b><br/><a href="79165?version=1&table=SRdistribution1">b0L-SRA</a>: $m_{\mathrm{CT}}$ <a href="79165?version=1&table=SRdistribution2">b0L-SRB</a>: $\mathrm{min[m_{T}(jet_{1-4}, E_{T}^{miss})]}$ <a href="79165?version=1&table=SRdistribution3">b0L-SRC</a>: ${\cal A}$ <a href="79165?version=1&table=SRdistribution4">b1L-SRA300-2j</a>: $\mathrm{m_{bb}}$ <a href="79165?version=1&table=SRdistribution5">b1L-SRA</a>: $\mathrm{m_{eff}}$ <a href="79165?version=1&table=SRdistribution6">b1L-SRB</a>: $\mathrm{m_{T}}$<br/><br/><b>Cross section upper limit:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Limitoncrosssection1">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection2">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection3">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection4">b0L-SRA550</a> <a href="79165?version=1&table=Limitoncrosssection5">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection6">b0L-SRC</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Limitoncrosssection7">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection8">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection9">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection10">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection11">b1L-best</a> <a href="79165?version=1&table=Limitoncrosssection12">b1L-SRA300-2j</a> <a href="79165?version=1&table=Limitoncrosssection13">b1L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection14">b1L-SRA600</a> <a href="79165?version=1&table=Limitoncrosssection15">b1L-SRA750</a> <a href="79165?version=1&table=Limitoncrosssection16">b1L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection17">best combination</a> <a href="79165?version=1&table=Limitoncrosssection18">A-LowMass</a> <a href="79165?version=1&table=Limitoncrosssection19">A-HighMass</a> <a href="79165?version=1&table=Limitoncrosssection20">B combination</a><br/><br/><b>Cutflow:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=CutflowTable1">b0L-SRA (1 TeV, 1 GeV)</a> <a href="79165?version=1&table=CutflowTable2">b0L-SRB (700 GeV, 450 GeV)</a> <a href="79165?version=1&table=CutflowTable3">b0L-SRC (450 GeV, 430 GeV)</a><br/><i>mixed:</i> <a href="79165?version=1&table=CutflowTable4">b1L-SRA (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable5">b1L-SRA300-2j (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable6">b0L-SRA (700 GeV, 300 GeV)</a><br/><br/><b>Truth Code</b> and <b>SLHA Files</b> for the cutflows are available under "Resources" (purple button on the left)
- - - - - - - - - - - - - - - - - - - - <br/><b>Acceptance:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Acceptance1">b0L-SRA350</a> <a href="79165?version=1&table=Acceptance2">b0L-SRA450</a> <a href="79165?version=1&table=Acceptance3">b0L-SRA550</a> <a href="79165?version=1&table=Acceptance4">b0L-SRB</a> <a href="79165?version=1&table=Acceptance5">b0L-SRC</a> <a href="79165?version=1&table=Acceptance6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Acceptance7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Acceptance8">b1L-SRA450</a> <a href="79165?version=1&table=Acceptance9">b1L-SRA600</a> <a href="79165?version=1&table=Acceptance10">b1L-SRA750</a> <a href="79165?version=1&table=Acceptance11">b1L-SRB</a> <a href="79165?version=1&table=Acceptance12">b1L-best</a><br/><br/><b>Efficiency:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Efficiency1">b0L-SRA350</a> <a href="79165?version=1&table=Efficiency2">b0L-SRA450</a> <a href="79165?version=1&table=Efficiency3">b0L-SRA550</a> <a href="79165?version=1&table=Efficiency4">b0L-SRB</a> <a href="79165?version=1&table=Efficiency5">b0L-SRC</a> <a href="79165?version=1&table=Efficiency6">b0L-best</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Efficiency7">b1L-SRA300-2j</a> <a href="79165?version=1&table=Efficiency8">b1L-SRA450</a> <a href="79165?version=1&table=Efficiency9">b1L-SRA600</a> <a href="79165?version=1&table=Efficiency10">b1L-SRA750</a> <a href="79165?version=1&table=Efficiency11">b1L-SRB</a> <a href="79165?version=1&table=Efficiency12">b1L-best</a><br/><br/><b>Best SR Mapping:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=BestSR4">b0L</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=BestSR1">b1L</a> <a href="79165?version=1&table=BestSR2">b0L</a> <a href="79165?version=1&table=BestSR3">combined</a><br/><br/><b>Exclusion Contour:</b><br/><i>symmetric:</i> b0L-SRA350 <a href="79165?version=1&table=Contour1">exp</a> <a href="79165?version=1&table=Contour2">obs</a> b0L-SRA450 <a href="79165?version=1&table=Contour5">exp</a> <a href="79165?version=1&table=Contour6">obs</a> b0L-SRA550 <a href="79165?version=1&table=Contour9">exp</a> <a href="79165?version=1&table=Contour10">obs</a> b0L-SRB <a href="79165?version=1&table=Contour11">exp</a> <a href="79165?version=1&table=Contour12">obs</a> b0L-SRC <a href="79165?version=1&table=Contour15">exp</a> <a href="79165?version=1&table=Contour16">obs</a> b0L-best <a href="79165?version=1&table=Contour17">exp</a> <a href="79165?version=1&table=Contour18">obs</a><br/><i>asymmetric:</i> b0L-SRA350 <a href="79165?version=1&table=Contour3">exp</a> <a href="79165?version=1&table=Contour4">obs</a> b0L-SRA450 <a href="79165?version=1&table=Contour7">exp</a> <a href="79165?version=1&table=Contour8">obs</a> b0L-SRB <a href="79165?version=1&table=Contour13">exp</a> <a href="79165?version=1&table=Contour14">obs</a> b0L-best <a href="79165?version=1&table=Contour19">exp</a> <a href="79165?version=1&table=Contour20">obs</a> b1L-SRA300-2j <a href="79165?version=1&table=Contour21">exp</a> <a href="79165?version=1&table=Contour22">obs</a> b1L-SRA450 <a href="79165?version=1&table=Contour23">exp</a> <a href="79165?version=1&table=Contour24">obs</a> b1L-SRA600 <a href="79165?version=1&table=Contour25">exp</a> <a href="79165?version=1&table=Contour26">obs</a> b1L-SRA750 <a href="79165?version=1&table=Contour27">exp</a> <a href="79165?version=1&table=Contour28">obs</a> b1L-SRB <a href="79165?version=1&table=Contour29">exp</a> <a href="79165?version=1&table=Contour30">obs</a> b1L-best <a href="79165?version=1&table=Contour31">exp</a> <a href="79165?version=1&table=Contour32">obs</a> A-LowMass <a href="79165?version=1&table=Contour33">exp</a> <a href="79165?version=1&table=Contour34">obs</a> A-HighMass <a href="79165?version=1&table=Contour35">exp</a> <a href="79165?version=1&table=Contour36">obs</a> B combination <a href="79165?version=1&table=Contour37">exp</a> <a href="79165?version=1&table=Contour38">obs</a> Best combination <a href="79165?version=1&table=Contour39">exp</a> <a href="79165?version=1&table=Contour40">obs</a><br/><br/><b>SR Distribution:</b><br/><a href="79165?version=1&table=SRdistribution1">b0L-SRA</a>: $m_{\mathrm{CT}}$ <a href="79165?version=1&table=SRdistribution2">b0L-SRB</a>: $\mathrm{min[m_{T}(jet_{1-4}, E_{T}^{miss})]}$ <a href="79165?version=1&table=SRdistribution3">b0L-SRC</a>: ${\cal A}$ <a href="79165?version=1&table=SRdistribution4">b1L-SRA300-2j</a>: $\mathrm{m_{bb}}$ <a href="79165?version=1&table=SRdistribution5">b1L-SRA</a>: $\mathrm{m_{eff}}$ <a href="79165?version=1&table=SRdistribution6">b1L-SRB</a>: $\mathrm{m_{T}}$<br/><br/><b>Cross section upper limit:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=Limitoncrosssection1">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection2">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection3">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection4">b0L-SRA550</a> <a href="79165?version=1&table=Limitoncrosssection5">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection6">b0L-SRC</a><br/><i>asymmetric:</i> <a href="79165?version=1&table=Limitoncrosssection7">b0L-best</a> <a href="79165?version=1&table=Limitoncrosssection8">b0L-SRA350</a> <a href="79165?version=1&table=Limitoncrosssection9">b0L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection10">b0L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection11">b1L-best</a> <a href="79165?version=1&table=Limitoncrosssection12">b1L-SRA300-2j</a> <a href="79165?version=1&table=Limitoncrosssection13">b1L-SRA450</a> <a href="79165?version=1&table=Limitoncrosssection14">b1L-SRA600</a> <a href="79165?version=1&table=Limitoncrosssection15">b1L-SRA750</a> <a href="79165?version=1&table=Limitoncrosssection16">b1L-SRB</a> <a href="79165?version=1&table=Limitoncrosssection17">best combination</a> <a href="79165?version=1&table=Limitoncrosssection18">A-LowMass</a> <a href="79165?version=1&table=Limitoncrosssection19">A-HighMass</a> <a href="79165?version=1&table=Limitoncrosssection20">B combination</a><br/><br/><b>Cutflow:</b><br/><i>symmetric:</i> <a href="79165?version=1&table=CutflowTable1">b0L-SRA (1 TeV, 1 GeV)</a> <a href="79165?version=1&table=CutflowTable2">b0L-SRB (700 GeV, 450 GeV)</a> <a href="79165?version=1&table=CutflowTable3">b0L-SRC (450 GeV, 430 GeV)</a><br/><i>mixed:</i> <a href="79165?version=1&table=CutflowTable4">b1L-SRA (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable5">b1L-SRA300-2j (700 GeV, 300 GeV)</a> <a href="79165?version=1&table=CutflowTable6">b0L-SRA (700 GeV, 300 GeV)</a><br/><br/><b>Truth Code</b> and <b>SLHA Files</b> for the cutflows are available under "Resources" (purple button on the left)
Signal acceptance (in %) in the ( M(SBOTTOM), M(NEUTRALINO) ) mass plane for the symmetric decay of the sbottom into bottom quark and neutralino, for the b0L-SRA350 signal region.
A search for massive coloured resonances which are pair-produced and decay into two jets is presented. The analysis uses 36.7 fb$^{-1}$ of $\sqrt{s}=$ 13 TeV pp collision data recorded by the ATLAS experiment at the LHC in 2015 and 2016. No significant deviation from the background prediction is observed. Results are interpreted in a SUSY simplified model where the lightest supersymmetric particle is the top squark, $\tilde{t}$, which decays promptly into two quarks through $R$-parity-violating couplings. Top squarks with masses in the range 100 GeV < $m_{\tilde{t}}$ < 410 GeV are excluded at 95% confidence level. If the decay is into a $b$-quark and a light quark, a dedicated selection requiring two $b$-tags is used to exclude masses in the ranges 100 GeV < $m_{\tilde{t}}$ < 470 GeV and 480 GeV < $m_{\tilde{t}}$ < 610 GeV. Additional limits are set on the pair-production of massive colour-octet resonances.
- - - - - - - - - - - - - - - - - - - - <p><b>Cutflows:</b><br> <a href="79059?version=1&table=CutflowTable1">Stop 100GeV</a><br> <a href="79059?version=1&table=CutflowTable2">Stop 500GeV</a><br> <a href="79059?version=1&table=CutflowTable3">Coloron 1500GeV</a><br> </p> <p><b>Event Yields:</b><br> <a href="79059?version=1&table=SRdistribution1">Inclusive stop SR</a><br> <a href="79059?version=1&table=SRdistribution2">Inclusive coloron SR </a><br> <a href="79059?version=1&table=SRdistribution3">b-tagged stop SR</a><br> </p> <p><b>Acceptances and Efficiencies:</b><br> <a href="79059?version=1&table=Acceptance1">Inclusive stop SR, before mass window</a><br> <a href="79059?version=1&table=Acceptance2">Inclusive stop SR, after mass window</a><br> <a href="79059?version=1&table=Acceptance3">Inclusive coloron SR, before mass window</a><br> <a href="79059?version=1&table=Acceptance4">Inclusive coloron SR, after mass window</a><br> <a href="79059?version=1&table=Acceptance5">b-tagged stop SR, before mass window</a><br> <a href="79059?version=1&table=Acceptance6">b-tagged stop SR, after mass window</a><br> </p> <p><b>Cross section upper limits:</b><br> <a href="79059?version=1&table=Limitoncrosssection1">Inclusive stop SR</a><br> <a href="79059?version=1&table=Limitoncrosssection2">Inclusive coloron SR</a><br> <a href="79059?version=1&table=Limitoncrosssection3">b-tagged stop SR</a><br> </p> <p><b>Truth Code</b> and <b>SLHA Files</b> for the cutflows are available under "Resources" (purple button on the left) </p>
Cutflow table for a pair produced top squark of 100 GeV decaying into a b- and an s-quark.
Cutflow table for a pair produced top squark of 500 GeV decaying into a b- and an s-quark.
This paper presents a study of $WW\gamma$ and $WZ\gamma$ triboson production using events from proton--proton collisions at a centre-of-mass energy of $\sqrt{s} = 8$ TeV recorded with the ATLAS detector at the LHC and corresponding to an integrated luminosity of 20.2 fb$^{-1}$. The $WW\gamma$ production cross-section is determined using a final state containing an electron, a muon, a photon, and neutrinos ($e\nu\mu\nu\gamma$). Upper limits on the production cross-section of the $e\nu\mu\nu\gamma$ final state and the $WW\gamma$ and $WZ\gamma$ final states containing an electron or a muon, two jets, a photon, and a neutrino ($e\nu jj\gamma$ or $\mu\nu jj\gamma$) are also derived. The results are compared to the cross-sections predicted by the Standard Model at next-to-leading order in the strong-coupling constant. In addition, upper limits on the production cross-sections are derived in a fiducial region optimised for a search for new physics beyond the Standard Model. The results are interpreted in the context of anomalous quartic gauge couplings using an effective field theory. Confidence intervals at 95% confidence level are derived for the 14 coupling coefficients to which $WW\gamma$ and $WZ\gamma$ production are sensitive.
Computed fiducial cross section in the $e\nu\mu\nu\gamma$ channel. The first uncertainty shown is the statistical uncertainty and the second one is the total systematic uncertainty including the uncertainty due to the luminosity. The theoretical prediction is determined with the VBFNLO generator and its uncertainty does not account for an uncertainty related to the scale introduced by restricting the jet multiplicity in the fully leptonic channel.
Observed and expected cross-section upper limits at 95\% CL for the different final states using the CL$_{\text{s}}$ method. The expected cross-section limits are computed assuming no signal is present. The last column shows the theory prediction for the signal cross-section ($\sigma_{\text{theo}}$) computed with the VBFNLO generator and corrected to particle level. The $\ell \nu jj \gamma$ cross-section corresponds to the average cross-section per lepton flavour in the semileptonic analysis and all events of the $e \nu jj \gamma$ and $\mu\nu jj \gamma$ final states are employed for the determination of this limit.
Observed and expected cross-section upper limits at 95\% CL using the CL$_{\text{s}}$ method for the different final states with the photon \et threshold optimised for maximal aQGC sensitivity. The expected cross-section limits are computed assuming the absence of $WV\gamma$ production. The last column shows the theory prediction for the SM signal cross-section computed with the VBFNLO generator and corrected to particle level. The $\ell \nu jj \gamma$ cross-section corresponds to the average cross-section per lepton flavour in the semileptonic analysis and all events of the $e \nu jj \gamma$ and $\mu\nu jj \gamma$ final states are employed for the determination of this limit.
A measurement of the production of three isolated photons in proton-proton collisions at a centre-of-mass energy $\sqrt{s}$ = 8 TeV is reported. The results are based on an integrated luminosity of 20.2 fb$^{-1}$ collected with the ATLAS detector at the LHC. The differential cross sections are measured as functions of the transverse energy of each photon, the difference in azimuthal angle and in pseudorapidity between pairs of photons, the invariant mass of pairs of photons, and the invariant mass of the triphoton system. A measurement of the inclusive fiducial cross section is also reported. Next-to-leading-order perturbative QCD predictions are compared to the cross-section measurements. The predictions underestimate the measurement of the inclusive fiducial cross section and the differential measurements at low photon transverse energies and invariant masses. They provide adequate descriptions of the measurements at high values of the photon transverse energies, invariant mass of pairs of photons, and invariant mass of the triphoton system.
The three isolated photons cross section with systematic and statistical uncertainties as a function of ET(Photon1).
The three isolated photons cross section with systematic and statistical uncertainties as a function of ET(Photon2).
The three isolated photons cross section with systematic and statistical uncertainties as a function of ET(Photon3).
A search is presented for the direct pair production of the stop, the supersymmetric partner of the top quark, that decays through an $R$-parity-violating coupling to a final state with two leptons and two jets, at least one of which is identified as a $b$-jet. The dataset corresponds to an integrated luminosity of 36.1 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of $\sqrt{s} = 13$ TeV, collected in 2015 and 2016 by the ATLAS detector at the LHC. No significant excess is observed over the Standard Model background, and exclusion limits are set on stop pair production at a 95% confidence level. Lower limits on the stop mass are set between 600 GeV and 1.5 TeV for branching ratios above 10% for decays to an electron or muon and a $b$-quark.
Signal acceptance (in %) in the (BRe,BRtau) plane for a 800 GeV stop, for the SR800 signal region.
Expected exclusion limit contour in the (BRe,BRtau) plane for a 600 GeV stop. All limits are computed at 95% CL.
Expected exclusion limit contour in the (BRe,BRtau) plane for a 600 GeV stop. All limits are computed at 95% CL.
A search for high-mass resonances decaying to $\tau\nu$ using proton-proton collisions at $\sqrt{s}$ = 13 TeV produced by the Large Hadron Collider is presented. Only $\tau$-lepton decays with hadrons in the final state are considered. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.1 fb$^{-1}$. No statistically significant excess above the Standard Model expectation is observed; model-independent upper limits are set on the visible $\tau\nu$ production cross section. Heavy $W^{\prime}$ bosons with masses less than 3.7 TeV in the Sequential Standard Model and masses less than 2.2-3.8 TeV depending on the coupling in the non-universal G(221) model are excluded at the 95% credibility level.
Observed and predicted $m_{\rm T}$ distributions including SSM and NU (cot$\phi$ = 5.5) $W^{\prime}$ signals with masses of 3 TeV. Please note that in the paper figure the bin content is divided by the bin width, but this is not done in the HepData table.
Observed and predicted $m_{\rm T}$ distributions including SSM and NU (cot$\phi$ = 5.5) $W^{\prime}$ signals with masses of 3 TeV. Please note that in the paper figure the bin content is divided by the bin width, but this is not done in the HepData table.
Observed and predicted $m_{\rm T}$ distributions including SSM and NU (cot$\phi$ = 5.5) $W^{\prime}$ signals with masses of 3 TeV. Please note that in the paper figure the bin content is divided by the bin width, but this is not done in the HepData table. The table also contains each background contribution to the Standard Model expectation separately with their statistical uncertainties.
A search for long-lived, massive particles predicted by many theories beyond the Standard Model is presented. The search targets final states with large missing transverse momentum and at least one high-mass displaced vertex with five or more tracks, and uses 32.8 fb$^{-1}$ of $\sqrt{s}$ = 13 TeV $pp$ collision data collected by the ATLAS detector at the LHC. The observed yield is consistent with the expected background. The results are used to extract 95\% CL exclusion limits on the production of long-lived gluinos with masses up to 2.37 TeV and lifetimes of $\mathcal{O}(10^{-2})$-$\mathcal{O}(10)$ ns in a simplified model inspired by Split Supersymmetry.
Vertex reconstruction efficiency as a function of radial position $R$ with and without the special LRT processing for one $R$-hadron signal sample with $m_{\tilde{g}} = 1.2$ TeV, $m_{\tilde{\chi}_{1}^{0}} = 100$ GeV and $\tau_{\tilde{g}} = 1$ ns. The efficiency is defined as the probability for a true LLP decay to be matched with a reconstructed DV fulfilling the vertex preselection criteria in events with a reconstructed primary vertex.
Vertex reconstruction efficiency as a function of radial position $R$ for two $R$-hadron signal samples with $m_{\tilde{g}} = 1.2$ TeV, $\tau_{\tilde{g}} = 1$ ns and different neutralino masses. The efficiency is defined as the probability for a true LLP decay to be matched with a reconstructed DV fulfilling the vertex preselection criteria in events with a reconstructed primary vertex.
Fractions of selected events for several signal MC samples with a gluino lifetime $\tau = 1$ ns, illustrating how $\mathcal{A}\times\varepsilon$ varies with the model parameters.
The production of exclusive $\gamma \gamma \rightarrow \mu^+ \mu^-$ events in proton--proton collisions at a centre-of-mass energy of 13 TeV is measured with the ATLAS detector at the LHC, using data corresponding to an integrated luminosity of 3.2 fb$^{-1}$. The measurement is performed for a dimuon invariant mass of 12 GeV $<m_{\mu^+\mu^-}<$ 70 GeV. The integrated cross-section is determined within a fiducial acceptance region of the ATLAS detector and differential cross-sections are measured as a function of the dimuon invariant mass. The results are compared to theoretical predictions that include corrections for absorptive effects.
The measured fiducial cross section.
Differential fiducial cross section in bins of the dimuon invariant mass. The measurements are listed together with the statistical and systematic uncertainties. The systematic uncertainties are separated into 2 uncorrelated, 7 correlated sources and the luminosity uncertainty. The sign of the uncertainty corresponds to a one standard deviation upward shift of the uncertainty source, where +/- means "+" and -/+ means "-".
Forum