Measurements of the yield and nuclear modification factor, $R_\mathrm{ AA}$, for inclusive jet production are performed using 0.49 nb$^{-1}$ of Pb+Pb data at $\sqrt{s_\mathrm{NN}} = 5.02$ TeV and 25 pb$^{-1}$ of $pp$ data at $\sqrt{s}=5.02$ TeV with the ATLAS detector at the LHC. Jets are reconstructed with the anti-$k_t$ algorithm with radius parameter $R=0.4$ and are measured over the transverse momentum range of 40-1000 GeV in six rapidity intervals covering $|y|<2.8$. The magnitude of $R_\mathrm{ AA}$ increases with increasing jet transverse momentum, reaching a value of approximately 0.6 at 1 TeV in the most central collisions. The magnitude of $R_\mathrm{ AA}$ also increases towards peripheral collisions. The value of $R_\mathrm{ AA}$ is independent of rapidity at low jet transverse momenta, but it is observed to decrease with increasing rapidity at high transverse momenta.
The ⟨TAA⟩ and ⟨Npart⟩ values and their uncertainties in each centrality bin.
No description provided.
No description provided.
A search has been performed for heavy resonances decaying to ZZ or ZW in 2$\ell$2q final states, with two charged leptons ($\ell=$ e,$\mu$) produced by the decay of a Z boson, and two quarks produced by the decay of a W or Z boson. The analysis is sensitive to resonances with masses in the range from 400 to 4500 GeV. Two categories are defined based on the merged or resolved reconstruction of the hadronically decaying vector boson, optimized for high- and low-mass resonances, respectively. The search is based on data collected during 2016 by the CMS experiment at the LHC in proton-proton collisions with a center-of-mass energy of $\sqrt{s}=$ 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. No excess is observed in the data above the standard model background expectation. Upper limits on the production cross section of heavy, narrow spin-1 and spin-2 resonances are derived as a function of the resonance mass, and exclusion limits on the production of W$'$ bosons and bulk graviton particles are calculated in the framework of the heavy vector triplet model and warped extra dimensions, respectively.
Distribution of the merged V candidate $\tau_{21}$, where the $\tau_{21}<$ 0.4 requirement has been removed, in data and simulation for events in the signal region of the low-mass analysis. The points show the data while the filled histograms show the background contributions. The gray band shows the statistical and systematic uncertainties in the background, while the dashed vertical region ("Higgs") shows the expected SM Higgs boson mass range, which is excluded from this analysis. A 600 GeV bulk graviton signal prediction is represented by the black dashed histogram; for visibility, the signal cross-section is increased by a factor of 5. The background normalization is derived from the final fit to the $m_{VZ}$ observable in data.
Distribution of the jet $p_{T}$ in data and simulation for events in the signal region of the low-mass analysis. The points show the data while the filled histograms show the background contributions. The gray band shows the statistical and systematic uncertainties in the background, while the dashed vertical region ("Higgs") shows the expected SM Higgs boson mass range, which is excluded from this analysis. A 600 GeV bulk graviton signal prediction is represented by the black dashed histogram; for visibility, the signal cross-section is increased by a factor of 5. The background normalization is derived from the final fit to the $m_{VZ}$ observable in data.
Distribution of V candidate $m_{j}$ in data and simulation for events in the signal regions of the low-mass search. The points show the data while the filled histograms show the background contributions. The gray band shows the statistical and systematic uncertainties in the background, while the dashed vertical region ("Higgs") shows the expected SM Higgs boson mass range, which is excluded from this analysis. A 600 GeV bulk graviton signal prediction is represented by the black dashed histogram; for visibility, the signal cross-section is increased by a factor of 5. The background normalization is derived from the final fit to the $m_{VZ}$ observable in data.
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. The table also contains each background contribution to the Standard Model expectation separately with their statistical uncertainties.
Number of expected Standard Model background events including total statistical and systematic uncertainty added in quadrature (calculated before applying the statistical fitting procedure), number of observed events, and the observed and expected 95% CL upper limits on the visible $\tau\nu$ production cross section, $\sigma_{\rm vis} = \sigma(pp \to \tau\nu +X) \cdot \mathcal{A} \cdot \varepsilon$, for $m_{\rm T}$ thresholds ranging from 250 to 1800 GeV. See HepData abstract for details on how to use this data for reinterpretation.
Observed and expected 95% CL upper limits on cross section times $\tau\nu$ branching fraction for $W^{\prime}_{\rm SSM}$.
Results are reported from a search for physics beyond the standard model in proton-proton collisions at a center-of-mass energy of $\sqrt{s} = $ 13 TeV. The search uses a signature of a single lepton, large jet and bottom quark jet multiplicities, and high sum of large-radius jet masses, without any requirement on the missing transverse momentum in an event. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ recorded by the CMS experiment at the LHC. No significant excess beyond the prediction from standard model processes is observed. The results are interpreted in terms of upper limits on the production cross section for $R$-parity violating supersymmetric extensions of the standard model using a benchmark model of gluino pair production, in which each gluino decays promptly via $ {\mathrm{\widetilde{g}}} \rightarrow \mathrm{t} \mathrm{b} \mathrm{s} $. Gluinos with a mass below 1610 GeV are excluded at 95% confidence level.
Figure 8. Observed cross section upper limits at 95% CL for a model of gluino pair production with gluino->tbs compared to the gluino pair production cross section.
Figure 8. Expected limits at 95% CL and their ±1 sigma variations for a model of gluino pair production with gluino->tbs compared to the gluino pair production cross section.
Figure 8. Expected limits at 95% CL and their ±2 sigma variations for a model of gluino pair production with gluino->tbs compared to the gluino pair production cross section.
Using a low background data sample of $9.7\times10^{5}$ $J\psi\rightarrow\gamma\eta^\prime$, $\eta^\prime\rightarrow\gamma\pi^+\pi^-$ events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII detector at BEPCII, the decay dynamics of $\eta^\prime\rightarrow\gamma\pi^+\pi^-$ are studied with both model-dependent and model-independent approaches. The contributions of $\omega$ and the $\rho(770)-\omega$ interference are observed for the first time in the decays $\eta^\prime\rightarrow\gamma\pi^+\pi^-$ in both approaches. Additionally, a contribution from the box anomaly or the $\rho(1450)$ resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
Numbers of events selected (Column 2), numbers of background events from sideband (Column 3), efficiencies (Column 4), and resolution RMS (Column 5) for different $M_{\pi^+\pi^-}$ bins.
A study of the associated production of a Z boson and a charm quark jet (Z + c), and a comparison to production with a b quark jet (Z + b), in pp collisions at a centre-of-mass energy of 8 TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7 fb$^{-1}$, collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with $p_{\rm T}^{\ell} > $ 20 GeV, ${|\eta^{\ell}|} < $ 2.1, 71 $ < m_{\ell\ell} < $ 111 GeV, and heavy flavour jets with $p_{\rm T}^{{\rm jet}} > $ 25 GeV and ${|\eta^{{\rm jet}}|} < $ 2.5. The Z + c production cross section is measured to be $\sigma({\mathrm{p}}{\mathrm{p}} \rightarrow \mathrm{Z} + \mathrm{c} + \mathrm{X}) {\cal B}(\mathrm{Z} \rightarrow \ell^+\ell^-) = $ 8.8 $ \pm $ 0.5 (stat) $ \pm $ 0.6 (syst) pb. The ratio of the Z + c and Z + b production cross sections is measured to be $\sigma({\mathrm{p}}{\mathrm{p}} \rightarrow \mathrm{Z} + \mathrm{c} + \mathrm{X}) / \sigma({\mathrm{p}}{\mathrm{p}} \rightarrow \mathrm{Z} + \mathrm{b} + \mathrm{X}) = $ 2.0 $ \pm $ 0.2 (stat) $ \pm $ 0.2 (syst). The Z + c production cross section and the cross section ratio are also measured as a function of the transverse momentum of the Z boson and of the heavy flavour jet. The measurements are compared with theoretical predictions.
Signal yields N(Z+c) and N(Z+b), efficiency*acceptance correction factors C(Z+c) and C(Z+b), cross section sigma(Z+c)B and cross section ratios sigma(Z+c)/sigma(Z+b) in the three categories (semileptonic, D+-, D*) and in the two Z boson decay channels (e+e-, mu+mu-). The factors that correct the acceptance and selection inefficiencies are also given. They include the relevant branching fraction for the corresponding channel. All uncertainties quoted in the table are statistical, except for those of the measured cross sections and cross section ratios where the first uncertainty is statistical and the second is the estimated systematic uncertainty
Z+c and Z+b signal yields, differential cross section dsigma(Z+c)/dpTZ times branching ratio and differential cross sections ratio dsigma(Z+c)/dpTZ / dsigma(Z+b)/dpTZ for three ranges of the transverse momentum of the Z boson in the semileptonic mode
Z+c and Z+b signal yields, differential cross section dsigma(Z+c)/dpTZ times branching ratio and differential cross sections ratio dsigma(Z+c)/dpTZ / dsigma(Z+b)/dpTZ for three ranges of the transverse momentum of the jet in the semileptonic mode
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.
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.
Expected exclusion limit contour in the (BRe,BRtau) plane for a 600 GeV stop. All limits are computed at 95% CL.
Observed 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 700 GeV stop. All limits are computed at 95% CL.
A search for neutral heavy resonances is performed in the $WW\to e\nu\mu\nu$ decay channel using $pp$ collision data corresponding to an integrated luminosity of 36.1 fb$^{-1}$, collected at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. No evidence of such heavy resonances is found. In the search for production via the quark--antiquark annihilation or gluon--gluon fusion process, upper limits on $\sigma_X \times B(X \to WW)$ as a function of the resonance mass are obtained in the mass range between 200 GeV and up to 5 TeV for various benchmark models: a Higgs-like scalar in different width scenarios, a two-Higgs-doublet model, a heavy vector triplet model, and a warped extra dimensions model. In the vector-boson fusion process, constraints are also obtained on these resonances, as well as on a Higgs boson in the Georgi--Machacek model and a heavy tensor particle coupling only to gauge bosons.
Figure 1, left, subfigure a, Acceptance times efficiency as a function of signal mass for the ggF or qqA production. The "0" efficiency mass point means there's no such signal sample for the corresponding model.
Figure 1, right, subfigure b, Acceptance times efficiency as a function of signal mass for the VBF production. The "0" efficiency mass point means there's no such signal sample for the corresponding model.
Figure 2, left, subfigure a, Transverse mass distribution in the ggF top-quark control regions. For NWA signals, the "0" value means lack of statistics.
A search for heavy neutral Higgs bosons and $Z^{\prime}$ bosons is performed using a data sample corresponding to an integrated luminosity of 36.1 fb$^{-1}$ from proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded by the ATLAS detector at the LHC during 2015 and 2016. The heavy resonance is assumed to decay to $\tau^+\tau^-$ with at least one tau lepton decaying to final states with hadrons and a neutrino. The search is performed in the mass range of 0.2-2.25 TeV for Higgs bosons and 0.2-4.0 TeV for $Z^{\prime}$ bosons. The data are in good agreement with the background predicted by the Standard Model. The results are interpreted in benchmark scenarios. In the context of the hMSSM scenario, the data exclude $\tan\beta > 1.0$ for $m_A$ = 0.25 TeV and $\tan\beta > 42$ for $m_A$ = 1.5 TeV at the 95% confidence level. For the Sequential Standard Model, $Z^{\prime}_\mathrm{SSM}$ with $m_{Z^{\prime}} < 2.42$ TeV is excluded at 95% confidence level, while $Z^{\prime}_\mathrm{NU}$ with $m_{Z^{\prime}} < 2.25$ TeV is excluded for the non-universal $G(221)$ model that exhibits enhanced couplings to third-generation fermions.
Observed and predicted mTtot distribution in the b-veto category of the 1l1tau_h channel. Despite listing this as an exclusive final state (as there must be no b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. In the paper, the first bin is cut off at 60 GeV for aesthetics but contains underflows down to 50 GeV as in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.
Observed and predicted mTtot distribution in the b-tag category of the 1l1tau_h channel. Despite listing this as an exclusive final state (as there must be at least one b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. In the paper, the first bin is cut off at 60 GeV for aesthetics but contains underflows down to 50 GeV as in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.
Observed and predicted mTtot distribution in the b-veto category of the 2tau_h channel. Despite listing this as an exclusive final state (as there must be no b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.
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