Evidence for X(3872) in PbPb collisions and studies of its prompt production at $\sqrt{s_\mathrm{NN}}=$ 5.02 TeV

The CMS collaboration Sirunyan, Albert M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 128 (2022) 032001, 2022.
Inspire Record 1848438 DOI 10.17182/hepdata.93882

The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (PbPb) collisions at a center-of-mass energy of $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV per nucleon pair, using the decay chain X(3872) $\to$ J$/\psi\, \pi^+\pi^- \to$ $\mu^+\mu^-\pi^+\pi^-$. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7 nb$^{-1}$. The measurement is performed in the rapidity and transverse momentum ranges $|y|$ $\lt$ 1.6 and 15 $\lt$ $p_\mathrm{T}$ $\lt$ 50 GeV$/c$. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to $\psi$(2S) yield ratio is found to be $\rho^\mathrm{PbPb} = $ 1.08 $\pm$ 0.49 (stat) $\pm$ 0.52 (syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state.

1 data table

The yield ratio $\rho^{\mathrm{PbPb}}$ of prompt X(3872) over $\psi(\mathrm{2S})$ production in PbPb collisions at 5.02 TeV


First measurement of large area jet transverse momentum spectra in heavy-ion collisions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 05 (2021) 284, 2021.
Inspire Record 1848440 DOI 10.17182/hepdata.93881

Jet production in lead-lead (PbPb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV is studied with the CMS detector at the LHC, using PbPb and pp data samples corresponding to integrated luminosities of 404 $\mu$b$^{-1}$ and 27.4 pb$^{-1}$, respectively. Jets with different areas are reconstructed using the anti-$k_\mathrm{T}$ algorithm by varying the distance parameter $R$. The measurements are performed using jets with transverse momenta ($p_\mathrm{T}$) greater than 200 GeV and in a pseudorapidity range of $|\eta|$$\lt$ 2. To reveal the medium modification of the jet spectra in PbPb collisions, the properly normalized ratio of spectra from PbPb and pp data is used to extract jet nuclear modification factors as functions of the PbPb collision centrality, $p_\mathrm{T}$ and, for the first time, as a function of $R$ up to 1.0. For the most central collisions, a strong suppression is observed for high-$p_\mathrm{T}$ jets reconstructed with all distance parameters, implying that a significant amount of jet energy is scattered to large angles. The dependence of jet suppression on $R$ is expected to be sensitive to both the jet energy loss mechanism and the medium response, and so the data are compared to several modern event generators and analytic calculations. The models considered do not fully reproduce the data.

18 data tables

Spectra of jets with |eta jet| < 2.0 for R = 0.2, for pp collisions and different centrality classes of PbPb collisions.

Spectra of jets with |eta jet| < 2.0 for R = 0.3, for pp collisions and different centrality classes of PbPb collisions.

Spectra of jets with |eta jet| < 2.0 for R = 0.4, for pp collisions and different centrality classes of PbPb collisions.

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Search for new phenomena in events with an energetic jet and missing transverse momentum in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Rev.D 103 (2021) 112006, 2021.
Inspire Record 1847779 DOI 10.17182/hepdata.102093

Results of a search for new physics in final states with an energetic jet and large missing transverse momentum are reported. The search uses proton-proton collision data corresponding to an integrated luminosity of 139 fb$^{-1}$ at a center-of-mass energy of 13 TeV collected in the period 2015-2018 with the ATLAS detector at the Large Hadron Collider. Compared to previous publications, in addition to an increase of almost a factor of four in the data size, the analysis implements a number of improvements in the signal selection and the background determination leading to enhanced sensitivity. Events are required to have at least one jet with transverse momentum above 150 GeV and no reconstructed leptons ($e$, $\mu$ or $\tau$) or photons. Several signal regions are considered with increasing requirements on the missing transverse momentum starting at 200 GeV. Overall agreement is observed between the number of events in data and the Standard Model predictions. Model-independent 95 % confidence-level limits on visible cross sections for new processes are obtained in the range between 736 fb and 0.3 fb with increasing missing transverse momentum. Results are also translated into improved exclusion limits in models with pair-produced weakly interacting dark-matter candidates, large extra spatial dimensions, supersymmetric particles in several compressed scenarios, axion-like particles, and new scalar particles in dark-energy-inspired models. In addition, the data are translated into bounds on the invisible branching ratio of the Higgs boson.

98 data tables

- - - - - - - - Overview of HEPData Record - - - - - - - - <br/><br/> <b>Post-fit $p_{\mathrm{T}}^{\mathrm{recoil}}$ distribution:</b> <ul> <li><a href="102093?version=1&table=HistogramCR1mu0b">CR1mu0b</a> <li><a href="102093?version=1&table=HistogramCR1e0b">CR1e0b</a> <li><a href="102093?version=1&table=HistogramCR1L1b">CR1L1b</a> <li><a href="102093?version=1&table=HistogramCR2mu">CR2mu</a> <li><a href="102093?version=1&table=HistogramCR2e">CR2e</a> <li><a href="102093?version=1&table=HistogramSR">SR</a> </ul> <b>Exclusion contours:</b> <ul> <li>Dark Matter axial-vector mediator: <ul> <li><a href="102093?version=1&table=ContourobsDMA">observed</a> <li><a href="102093?version=1&table=Contourobs_p1DMA">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourobs_m1DMA">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=ContourexpDMA">expected</a> <li><a href="102093?version=1&table=Contourexp_p1DMA">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m1DMA">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_p2DMA">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m2DMA">-2 $\sigma$ expected</a> </ul> <li>Dark Matter pseudo-scalar mediator: <ul> <li><a href="102093?version=1&table=ContourobsDMP">observed</a> <li><a href="102093?version=1&table=Contourobs_p1DMP">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourobs_m1DMP">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=ContourexpDMP">expected</a> <li><a href="102093?version=1&table=Contourexp_p1DMP">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m1DMP">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_p2DMP">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m2DMP">-2 $\sigma$ expected</a> </ul> <li>Dark Matter vector mediator: <ul> <li><a href="102093?version=1&table=ContourobsDMV">observed</a> <li><a href="102093?version=1&table=Contourobs_p1DMV">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourobs_m1DMV">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=ContourexpDMV">expected</a> <li><a href="102093?version=1&table=Contourexp_p1DMV">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m1DMV">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_p2DMV">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourexp_m2DMV">-2 $\sigma$ expected</a> </ul> <li>Dark Matter spin-dependent WIMP-nucleon scattering cross-section: <a href="102093?version=1&table=ContourSDneutron">observed</a> <li>Dark Matter spin-independent WIMP-nucleon scattering cross-section: <a href="102093?version=1&table=ContourSInucleon">observed</a> <li>Dark Matter WIMP annihilation rate: <a href="102093?version=1&table=ContourID">observed</a> <li>SUSY stop pair production: <ul> <li><a href="102093?version=1&table=Contourg_obsTT_directCC">observed</a> <li><a href="102093?version=1&table=Contourg_obs_p1TT_directCC">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_obs_m1TT_directCC">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_expTT_directCC">expected</a> <li><a href="102093?version=1&table=Contourg_exp_p1TT_directCC">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m1TT_directCC">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_p2TT_directCC">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m2TT_directCC">-2 $\sigma$ expected</a> </ul> <li>SUSY stop pair production (4-body decay): <ul> <li><a href="102093?version=1&table=Contourg_obsTT_bffN">observed</a> <li><a href="102093?version=1&table=Contourg_obs_p1TT_bffN">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_obs_m1TT_bffN">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_expTT_bffN">expected</a> <li><a href="102093?version=1&table=Contourg_exp_p1TT_bffN">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m1TT_bffN">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_p2TT_bffN">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m2TT_bffN">-2 $\sigma$ expected</a> </ul> <li>SUSY sbottom pair production: <ul> <li><a href="102093?version=1&table=Contourg_obsBB">observed</a> <li><a href="102093?version=1&table=Contourg_obs_p1BB">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_obs_m1BB">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_expBB">expected</a> <li><a href="102093?version=1&table=Contourg_exp_p1BB">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m1BB">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_p2BB">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m2BB">-2 $\sigma$ expected</a> </ul> <li>SUSY squark pair production: <ul> <li><a href="102093?version=1&table=Contourg_obsSS">observed</a> <li><a href="102093?version=1&table=Contourg_obs_p1SS">+1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_obs_m1SS">-1 $\sigma_{\mathrm{theory}}^{\mathrm{PDF+scale}}$ observed</a> <li><a href="102093?version=1&table=Contourg_expSS">expected</a> <li><a href="102093?version=1&table=Contourg_exp_p1SS">+1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m1SS">-1 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_p2SS">+2 $\sigma$ expected</a> <li><a href="102093?version=1&table=Contourg_exp_m2SS">-2 $\sigma$ expected</a> </ul> <li>Dark energy: <a href="102093?version=1&table=ContourDE">observed and expected</a> <li>ADD: <a href="102093?version=1&table=ContourADD">observed and expected</a> <li>Axion-like particles: <a href="102093?version=1&table=ContourALPs">observed and expected</a> </ul> <b>Impact of systematic uncertainties:</b> <a href="102093?version=1&table=Tablesystimpacts">Table</a><br/><br/> <b>Yields of exclusive regions:</b> <a href="102093?version=1&table=TableyieldsEM0">EM0</a> <a href="102093?version=1&table=TableyieldsEM1">EM1</a> <a href="102093?version=1&table=TableyieldsEM2">EM2</a> <a href="102093?version=1&table=TableyieldsEM3">EM3</a> <a href="102093?version=1&table=TableyieldsEM4">EM4</a> <a href="102093?version=1&table=TableyieldsEM5">EM5</a> <a href="102093?version=1&table=TableyieldsEM6">EM6</a> <a href="102093?version=1&table=TableyieldsEM7">EM7</a> <a href="102093?version=1&table=TableyieldsEM8">EM8</a> <a href="102093?version=1&table=TableyieldsEM9">EM9</a> <a href="102093?version=1&table=TableyieldsEM10">EM10</a> <a href="102093?version=1&table=TableyieldsEM11">EM11</a> <a href="102093?version=1&table=TableyieldsEM12">EM12</a><br/><br/> <b>Yields of inclusive regions:</b> <a href="102093?version=1&table=TableyieldsIM0">IM0</a> <a href="102093?version=1&table=TableyieldsIM1">IM1</a> <a href="102093?version=1&table=TableyieldsIM2">IM2</a> <a href="102093?version=1&table=TableyieldsIM3">IM3</a> <a href="102093?version=1&table=TableyieldsIM4">IM4</a> <a href="102093?version=1&table=TableyieldsIM5">IM5</a> <a href="102093?version=1&table=TableyieldsIM6">IM6</a> <a href="102093?version=1&table=TableyieldsIM7">IM7</a> <a href="102093?version=1&table=TableyieldsIM8">IM8</a> <a href="102093?version=1&table=TableyieldsIM9">IM9</a> <a href="102093?version=1&table=TableyieldsIM10">IM10</a> <a href="102093?version=1&table=TableyieldsIM11">IM11</a> <a href="102093?version=1&table=TableyieldsIM12">IM12</a><br/><br/> <b>Cutflows:</b><br/><br/> Signals filtered with a truth $E_\mathrm{T}^\mathrm{miss}$ cut at: <ul> <li> <a href="102093?version=1&table=Tablecutflows150GeV">150 GeV</a> <li> <a href="102093?version=1&table=Tablecutflows350GeV">350 GeV</a> </ul>

The measured $p_{\mathrm{T}}^{\mathrm{recoil}}$ distributions in the $W \rightarrow \mu \nu $ control region, compared with the background predictions as estimated after the simultaneous, binned background-only fit to the data in the control regions. The last bin of the distribution contains overflows.

The measured $p_{\mathrm{T}}^{\mathrm{recoil}}$ distributions in the $W \rightarrow e \nu$ control region, compared with the background predictions as estimated after the simultaneous, binned background-only fit to the data in the control regions. The last bin of the distribution contains overflows.

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Search for charged Higgs bosons decaying into a top quark and a bottom quark at $\sqrt{s}$=13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Dale ; et al.
JHEP 06 (2021) 145, 2021.
Inspire Record 1847643 DOI 10.17182/hepdata.100427

A search for charged Higgs bosons decaying into a top quark and a bottom quark is presented. The data analysed correspond to 139 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$=13TeV, recorded with the ATLAS detector at the LHC. The production of a heavy charged Higgs boson in association with a top quark and a bottom quark, $pp\rightarrow tbH^{+}\rightarrow tbtb$, is explored in the $H^+$ mass range from 200 to 2000 GeV using final states with jets and one electron or muon. Events are categorised according to the multiplicity of jets and $b$-tagged jets, and multivariate analysis techniques are used to discriminate between signal and background events. No significant excess above the background-only hypothesis is observed and exclusion limits are derived for the production cross-section times branching ratio of a charged Higgs boson as a function of its mass; they range from 3.6 pb at 200 GeV to 0.036 pb at 2000 GeV at 95% confidence level. The results are interpreted in the hMSSM and $M_h^{125}$ scenarios.

9 data tables

Observed and expected upper limits for the production of $H^+\rightarrow tb$ in association with a top quark and a bottom quark. The bands surrounding the expected limit show the 68% and 95% confidence intervals. The red lines show the observed and expected 95% CL exclusion limits obtained with the 36 fb$^{-1}$ data sample. Theory predictions are shown for two representative values of $\tan\beta$ in the hMSSM benchmark scenario. Uncertainties in the predicted $H^+$ cross-sections or branching ratios are not considered.

Observed and expected limits on $\tan\beta$ as a function of $m_{H^+}$ in the hMSSM scenario. Limits are shown for $\tan\beta$ values in the range of 0.5-60 due to the availability of the model prediction. The bands surrounding the expected limits show the 68% and 95% confidence intervals. Uncertainties in the predicted $H^+$ cross-sections or branching ratios are not considered.

Observed and expected limits on $\tan\beta$ as a function of $m_{H^+}$ in the $M_h^{125}$ scenario. Limits are shown for $\tan\beta$ values in the range of 0.5-60 due to the availability of the model prediction. The bands surrounding the expected limits show the 68% and 95% confidence intervals. Uncertainties in the predicted $H^+$ cross-sections or branching ratios are not considered.

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Version 2
Measurements of angular distance and momentum ratio distributions in three-jet and Z + two-jet final states in pp collisions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 81 (2021) 852, 2021.
Inspire Record 1847230 DOI 10.17182/hepdata.106642

Collinear (small-angle) and large-angle, as well as soft and hard radiations are investigated in three-jet and Z + two-jet events collected in proton-proton collisions at the LHC. The normalized production cross sections are measured as a function of the ratio of transverse momenta of two jets and their angular separation. The measurements in the three-jet and Z + two-jet events are based on data collected at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 19.8 fb$^{-1}$. The Z + two-jet events are reconstructed in the dimuon decay channel of the Z boson. The three-jet measurement is extended to include $\sqrt{s} =$ 13 TeV data corresponding to an integrated luminosity of 2.3 fb$^{-1}$. The results are compared to predictions from event generators that include parton showers, multiple parton interactions, and hadronization. The collinear and soft regions are in general well described by parton showers, whereas the regions of large angular separation are often best described by calculations using higher-order matrix elements.

24 data tables

Three-jet events $p_{\mathrm{T}3}/p_{\mathrm{T}2}$ for small-angle radiation ($\Delta R_{23}$ < 1.0)

Three-jet events $p_{\mathrm{T}3}/p_{\mathrm{T}2}$ for small-angle radiation ($\Delta R_{23}$ < 1.0)

Three-jet events $p_{\mathrm{T}3}/p_{\mathrm{T}2}$ for large-angle radiation ($\Delta R_{23}$ > 1.0)

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Search for a heavy vector resonance decaying to a Z boson and a Higgs boson in proton-proton collisions at $\sqrt{s} = $ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J.C 81 (2021) 688, 2021.
Inspire Record 1846987 DOI 10.17182/hepdata.101374

A search is presented for a heavy vector resonance decaying into a Z boson and the standard model Higgs boson, where the Z boson is identified through its leptonic decays to electrons, muons, or neutrinos, and the Higgs boson is identified through its hadronic decays. The search is performed in a Lorentz-boosted regime and is based on data collected from 2016 to 2018 at the CERN LHC, corresponding to an integrated luminosity of 137 fb$^{-1}$. Upper limits are derived on the production of a narrow heavy resonance Z', and a mass below 3.5 and 3.7 TeV is excluded at 95% confidence level in models where the heavy vector boson couples exclusively to fermions and to bosons, respectively. These are the most stringent limits placed on the Heavy Vector Triplet Z' model to date. If the heavy vector boson couples exclusively to standard model bosons, upper limits on the product of the cross section and branching fraction are set between 23 and 0.3 fb for a Z' mass between 0.8 and 4.6 TeV, respectively. This is the first limit set on a heavy vector boson coupling exclusively to standard model bosons in its production and decay.

21 data tables

The product of signal acceptance and efficiency in the 0l categories for the signal produced via qqbar annihilation.

The product of signal acceptance and efficiency in the 2l categories for the signal produced via qqbar annihilation.

The product of signal acceptance and efficiency in the 0l categories for the signal produced via vector boson fusion.

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Search for top squarks in final states with two top quarks and several light-flavor jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.D 104 (2021) 032006, 2021.
Inspire Record 1846679 DOI 10.17182/hepdata.103064

Many new physics models, including versions of supersymmetry characterized by $R$-parity violation (RPV), compressed mass spectra, long decay chains, or additional hidden sectors, predict the production of events with top quarks, low missing transverse momentum, and many additional quarks or gluons. The results of a search for new physics in events with two top quarks and additional jets are reported. The search is performed using events with at least seven jets and exactly one electron or muon. No requirement on missing transverse momentum is imposed. The study is based on a sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV corresponding to 137 fb$^{-1}$ of integrated luminosity collected with the CMS detector at the LHC in 2016-2018. The data are used to determine best fit values and upper limits on the cross section for pair production of top squarks in scenarios of RPV and stealth supersymmetry. Top squark masses up to 670 (870) GeV are excluded at 95% confidence level for the RPV (stealth) scenario, and the maximum observed local signal significance is 2.8 standard deviations for the RPV scenario with top squark mass of 400 GeV.

10 data tables

Fitted background prediction and observed data counts for 2016 as functions of $N_{\text{jets}}$ in each of the four $S_{\textrm{NN}}$ bins. The signal distributions normalized to the predicted cross section for the RPV model with $m_{\tilde{t}}$ = 450 GeV and the stealth SYY model with $m_{\tilde{t}}$ = 850 GeV are shown for comparison.

Fitted background prediction and observed data counts for 2017 as functions of $N_{\text{jets}}$ in each of the four $S_{\textrm{NN}}$ bins. The signal distributions normalized to the predicted cross section for the RPV model with $m_{\tilde{t}}$ = 450 GeV and the stealth SYY model with $m_{\tilde{t}}$ = 850 GeV are shown for comparison.

Fitted background prediction and observed data counts for 2018A as functions of $N_{\text{jets}}$ in each of the four $S_{\textrm{NN}}$ bins. The signal distributions normalized to the predicted cross section for the RPV model with $m_{\tilde{t}}$ = 450 GeV and the stealth SYY model with $m_{\tilde{t}}$ = 850 GeV are shown for comparison.

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Observation of a new excited beauty strange baryon decaying to $\Xi^-_\mathrm{b} \pi^+ \pi^-$

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 126 (2021) 252003, 2021.
Inspire Record 1845579 DOI 10.17182/hepdata.102493

The $\Xi^-_\mathrm{b} \pi^+ \pi^-$ invariant mass spectrum is investigated with an event sample of proton-proton collisions at $\sqrt{s} = $ 13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140 fb$^{-1}$. The ground state $\Xi^-_\mathrm{b}$ is reconstructed via its decays to J$/\psi \Xi^-$ and J$/\psi \Xi^-\Lambda$K$^-$. A narrow resonance, labeled $\Xi_\mathrm{b}$(6100)$^-$, is observed at a $\Xi^-_\mathrm{b} \pi^+ \pi^-$ invariant mass of 6100.3 $\pm$ 0.2 (stat) $\pm$ 0.1 (syst) $\pm$ 0.6 ($\Xi^-_\mathrm{b}$) MeV, where the last uncertainty reflects the precision of the $\Xi^-_\mathrm{b}$ baryon mass. The upper limit on the $\Xi_\mathrm{b}$(6100)$^-$ natural width is determined to be 1.9 MeV at 95% confidence level. Following analogies with the established excited $\Xi_\mathrm{c}$ baryon states, the new $\Xi_\mathrm{b}$(6100)$^-$ resonance and its decay sequence are consistent with the orbitally excited $\Xi^-_\mathrm{b}$ baryon, with spin and parity quantum numbers $J^P=$ 3/2$^-$.

3 data tables

Measurement of W$\gamma$ production cross section in proton-proton collisions at $\sqrt{s} =$ 13 TeV and constraints on effective field theory coefficients

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev.Lett. 126 (2021) 252002, 2021.
Inspire Record 1844754 DOI 10.17182/hepdata.102462

A fiducial cross section for W$\gamma$ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb$^{-1}$ of data collected using the CMS detector at the LHC. The W $\to$ e$\nu$ and $\mu\nu$ decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.

4 data tables

The measured Wgamma fiducial cross section and corresponding theoretical predictions from MadGraph5_aMC@NLO and POWHEG. The MadGraph5_aMC@NLO prediction includes 0 and 1 jets in the matrix element at NLO in QCD. The POWHEG prediction uses the C-NLO method described in https://arxiv.org/abs/1408.5766. The cross section is measured in a fiducial region defined with isolated prompt photons and isolated prompt dressed leptons (electrons and muons). A lepton or photon is considered isolated if the pt sum of all stable particles within Delta R = 0.4, divided by the pt of the lepton or photon, is less than 0.5. A lepton is considered prompt if it originates from the hard process or from the decay of a tau lepton that originates from the hard process; a photon is considered prompt if it originates from the hard process or an FSR or ISR process involving a particle that originates from the hard process. A lepton is dressed by adding to its four-momentum the four-momenta of all photons within DeltaR = 0.1; this procedure is intended to restore the lepton to its pre-FSR state. The fiducial region kinematic requirements are: photon and lepton |eta|<2.5 and pt > 25 GeV, and DeltaR(lepton,photon) > 0.5.

Data and SM expected event yields corresponding to photon pt distribution used to extract aTGC limits.

95% CL limits on effective field theory parameters in Wgamma events. No unitarity regularisation scheme is applied. All parameters are fixed to their SM values except the one that is fitted.

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Search for new phenomena in events with two opposite-charge leptons, jets and missing transverse momentum in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 04 (2021) 165, 2021.
Inspire Record 1844425 DOI 10.17182/hepdata.98627

The results of a search for direct pair production of top squarks and for dark matter in events with two opposite-charge leptons (electrons or muons), jets and missing transverse momentum are reported, using 139 fb$^{-1}$ of integrated luminosity from proton-proton collisions at $\sqrt{s} = 13$ TeV, collected by the ATLAS detector at the Large Hadron Collider during Run 2 (2015-2018). This search considers the pair production of top squarks and is sensitive across a wide range of mass differences between the top squark and the lightest neutralino. Additionally, spin-0 mediator dark-matter models are considered, in which the mediator is produced in association with a pair of top quarks. The mediator subsequently decays to a pair of dark-matter particles. No significant excess of events is observed above the Standard Model background, and limits are set at 95% confidence level. The results exclude top squark masses up to about 1 TeV, and masses of the lightest neutralino up to about 500 GeV. Limits on dark-matter production are set for scalar (pseudoscalar) mediator masses up to about 250 (300) GeV.

196 data tables

Two-body selection. Distributions of $m_{T2}$ in $SR^{2-body}_{110,\infty}$ for (a) different-flavour and (b) same-flavour events satisfying the selection criteria of the given SR, except the one for the presented variable, after the background fit. The contributions from all SM backgrounds are shown as a histogram stack. ''Others'' includes contributions from $VVV$, $t\bar{t} t$, $t\bar{t}$, $t\bar{t} W$, $t\bar{t} WW$, $t\bar{t} WZ$, $t\bar{t} H$, and $tZ$ processes. The hatched bands represent the total statistical and systematic uncertainty. The rightmost bin of each plot includes overflow events. Reference dark-matter signal models are overlayed for comparison. Red arrows in the upper panels indicate the signal region selection criteria. The bottom panels show the ratio of the observed data to the total SM background prediction, with hatched bands representing the total uncertainty in the background prediction.

Two-body selection. Distributions of $m_{T2}$ in $SR^{2-body}_{110,\infty}$ for (a) different-flavour and (b) same-flavour events satisfying the selection criteria of the given SR, except the one for the presented variable, after the background fit. The contributions from all SM backgrounds are shown as a histogram stack. ''Others'' includes contributions from $VVV$, $t\bar{t} t$, $t\bar{t}$, $t\bar{t} W$, $t\bar{t} WW$, $t\bar{t} WZ$, $t\bar{t} H$, and $tZ$ processes. The hatched bands represent the total statistical and systematic uncertainty. The rightmost bin of each plot includes overflow events. Reference dark-matter signal models are overlayed for comparison. Red arrows in the upper panels indicate the signal region selection criteria. The bottom panels show the ratio of the observed data to the total SM background prediction, with hatched bands representing the total uncertainty in the background prediction.

Three-body selection. Distributions of $M_{\Delta}^R$ in (a,b) $SR_{W}^{3-body}$ and (c,d) $SR_{T}^{3-body}$ for (left) same-flavour and (right) different-flavour events satisfying the selection criteria of the given SR, except the one for the presented variable, after the background fit. The contributions from all SM backgrounds are shown as a histogram stack. ''Others'' includes contributions from $VVV$, $t\bar{t} t$, $t\bar{t}t\bar{t}$, $t\bar{t} W$, $t\bar{t} WW$, $t\bar{t} WZ$, $t\bar{t} H$, and $tZ$ processes. The hatched bands represent the total statistical and systematic uncertainty. The rightmost bin of each plot includes overflow events. Reference top squark pair production signal models are overlayed for comparison. Red arrows in the upper panels indicate the signal region selection criteria. The bottom panels show the ratio of the observed data to the total SM background prediction, with hatched bands representing the total uncertainty in the background prediction; red arrows show data outside the vertical-axis range.

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