Date

Search for resonant production of pairs of dijet resonances through broad mediators in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-EXO-24-038, 2025.
Inspire Record 2954159 DOI 10.17182/hepdata.159918

A reinterpretation of a prior narrow-resonance search is performed to investigate the resonant production of pairs of dijet resonances via broad mediators. This analysis targets events with four resolved jets, requiring dijet invariant masses greater than 0.2 TeV and four-jet invariant masses greater than 1.6 TeV. The search uses a data sample corresponding to an integrated luminosity of 138 fb$^{-1}$ collected by the CMS experiment in proton-proton collisions at $\sqrt{s}$ = 13 TeV. The reinterpretation considers the production of new heavy four-jet resonances, with widths ranging from 1.5 to 10% of their mass, which decay to a pair of dijet resonances. This analysis probes resonant production in the four-jet and dijet mass distributions. Upper limits at 95% confidence level and significances are reported on the production cross section of new resonances as functions of their widths and masses, between 2 and 10 TeV. In particular, at a four-jet resonance mass of 8.6 TeV, the local (global) significance ranges from 3.9 (1.6) to 3.6 (1.4) standard deviations (s.d.) as the resonance width is increased from 1.5 to 10%. This relative insensitivity to the choice of width indicates that a broad resonance is an equally valid interpretation of this excess. The broad resonance hypothesis at a resonance mass of 8.6 TeV is supported by the presence of an event with a four-jet mass of 5.8 TeV and an average dijet mass of 2.0 TeV. Also, we report the reinterpretation of a second effect, at a four-jet resonance mass of 3.6 TeV, which has a local (global) significance of up to 3.9 (2.2) s.d.

51 data tables

Observed number of events within bins of the four-jet mass and the average mass of the two dijets.

Observed number of events within bins of the four-jet mass and the ratio $\alpha$, which is the average dijet mass divided by the four-jet mass.

Predictions of a leading order (LO) QCD simulation, normalized to an integrated luminosity of 138 fb$^{-1}$. The number of events are examined within bins of the four-jet mass and the average mass of the two dijets.

More…

Probing the flavour structure of dimension-6 EFT operators in multilepton final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-TOP-23-009, 2025.
Inspire Record 2953423 DOI 10.17182/hepdata.157849

An analysis of the flavour structure of dimension-6 effective field theory (EFT) operators in multilepton final states is presented, focusing on the interactions involving Z bosons. For the first time, the flavour structure of these operators is disentangled by simultaneously probing the interactions with different quark generations. The analysis targets the associated production of a top quark pair and a Z boson, as well as diboson processes in final states with at least three leptons, which can be electrons or muons. The data were recorded by the CMS experiment in the years 2016$-$2018 in proton-proton collisions at a centre-of-mass energy of 13 TeV and correspond to an integrated luminosity of 138 fb$^{-1}$. Consistency with the standard model of particle physics is observed and limits are set on the selected Wilson coefficients, split into couplings to light- and heavy-quark generations.

0 data tables

Exploring small-angle emissions in charm quark jets in proton-proton collisions at $\sqrt{s}$ = 5.02 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-HIN-24-007, 2025.
Inspire Record 2950741 DOI 10.17182/hepdata.156758

A measurement of the angular structure of jets containing a prompt D$^0$ meson and of inclusive jets in proton-proton collisions at the LHC at a center-of-mass energy of 5.02 TeV is presented. The data corresponding to an integrated luminosity of 301 pb$^{-1}$ were collected by the CMS experiment in 2017. Two jet grooming algorithms, late-$k_\mathrm{T}$ and soft drop, are used to study the intrajet radiation pattern using iterative Cambridge$-$Aachen declustering. The splitting-angle distributions of jets with transverse momentum ($p_\mathrm{T}$) of around 100 GeV, obtained with these two algorithms, show that there is a shift of the distribution for jets containing a prompt D$^0$ meson with respect to inclusive jets. The shift observed in the late-$k_\mathrm{T}$ grooming approach is consistent with the dead-cone effect, whereas the shift for splittings selected with the soft-drop algorithm appears to be dominated by gluon splitting to charm quark-antiquark pairs. The measured distributions are corrected to the particle level and can be used to constrain model predictions for the substructure of high-$p_\mathrm{T}$ charm quark jets.

0 data tables

Evidence of medium response to hard probes using correlations of Z bosons with hadrons in heavy ion collisions

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-HIN-23-006, 2025.
Inspire Record 2945894 DOI 10.17182/hepdata.156186

The first measurement of pseudorapidity and azimuthal angle distributions relative to the momentum vector of a Z boson for low transverse momentum ($p_\mathrm{T}$) charged hadrons in lead-lead (PbPb) collisions is presented. By studying the hadrons produced in an event with a high-$p_\mathrm{T}$ Z boson (40 $\lt$$p_\mathrm{T}$$\lt$ 350 GeV), the analysis probes how the quark-gluon plasma (QGP) medium created in these collisions affects the parton recoiling opposite to the Z boson. Utilizing PbPb data at a nucleon-nucleon center-of-mass energy $\sqrt{s_{_\mathrm{NN}}}$ = 5.02 TeV from 2018 with an integrated luminosity of 1.67 nb$^{-1}$ and proton-proton (pp) data at the same energy from 2017 with 301 pb$^{-1}$, the distributions are examined in bins of charged-hadron $p_\mathrm{T}$. A significant modification of the distributions for charged hadrons in the range 1$\lt$$p_\mathrm{T}$$\lt$ 2 GeV in PbPb collisions is observed when compared to reference measurements from pp collisions. The data provide new information about the correlation between hard and soft particles in heavy ion collisions, which can be used to test predictions of various jet quenching models. The results are consistent with expectations of a hydrodynamic wake created when the QGP is depleted of energy by the parton propagating through it. Based on comparisons of PbPb data with pp references and predictions from theoretical models, this Letter presents the first evidence of medium-recoil and medium-hole effects caused by a hard probe.

30 data tables

The $\Delta\phi_{ch,Z}$ spectra for events with Z boson $p_{T}^Z > 40$ GeV and charged-hadrons with $1 <p_T < 2$ GeV in pp collisions.

The $\Delta\phi_{ch,Z}$ spectra for events with Z boson $p_{T}^Z > 40$ GeV and charged-hadrons with $2 <p_T < 4$ GeV in pp collisions.

The $\Delta\phi_{ch,Z}$ spectra for events with Z boson $p_{T}^Z > 40$ GeV and charged-hadrons with $4 <p_T < 10$ GeV in pp collisions.

More…

Search for heavy pseudoscalar and scalar bosons decaying to a top quark pair in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-HIG-22-013, 2025.
Inspire Record 2942928 DOI 10.17182/hepdata.159298

A search for pseudoscalar or scalar bosons decaying to a top quark pair ($\mathrm{t\bar{t}}$) in final states with one or two charged leptons is presented. The analyzed proton-proton collision data was recorded at $\sqrt{s}$ = 13 TeV by the CMS experiment at the CERN LHC and corresponds to an integrated luminosity of 138 fb$^{-1}$. The invariant mass $m_\mathrm{t\bar{t}}$ of the reconstructed $\mathrm{t\bar{t}}$ system and variables sensitive to its spin and parity are used to discriminate against the standard model $\mathrm{t\bar{t}}$ background. Interference between pseudoscalar or scalar boson production and the standard model $\mathrm{t\bar{t}}$ continuum is included, leading to peak-dip structures in the $m_\mathrm{t\bar{t}}$ distribution. An excess of the data above the background prediction, based on perturbative quantum chromodynamics (QCD) calculations, is observed near the kinematic $\mathrm{t\bar{t}}$ production threshold, while good agreement is found for high $m_\mathrm{t\bar{t}}$. The data are consistent with the background prediction if the contribution from the production of a color-singlet ${}^1\mathrm{S}_0^{[1]}$$\mathrm{t\bar{t}}$ quasi-bound state $η_\mathrm{t}$, predicted by nonrelativistic QCD, is added. Upper limits at 95% confidence level are set on the coupling between the pseudoscalar or scalar bosons and the top quark for boson masses in the range 365$-$1000 GeV, relative widths between 0.5 and 25%, and two background scenarios with or without $η_\mathrm{t}$ contribution.

847 data tables

Observed values of twice the negative log-likelihood with respect to the SM (corresponding to $g_{A t \bar t} = g_{H t \bar t} = 0$) for the simultaneous presence of A, $m_A = 450$ GeV, $\Gamma_A/m_A = 5.0$% and H, $m_H = 400$ GeV, $\Gamma_H/m_H = 2.0$% as a function of the coupling modifiers $g_{A t \bar t}$ and $g_{H t \bar t}$.

Observed values of twice the negative log-likelihood with respect to the SM (corresponding to $g_{A t \bar t} = g_{H t \bar t} = 0$) for the simultaneous presence of A, $m_A = 450$ GeV, $\Gamma_A/m_A = 21.0$% and H, $m_H = 700$ GeV, $\Gamma_H/m_H = 2.0$% as a function of the coupling modifiers $g_{A t \bar t}$ and $g_{H t \bar t}$.

Observed values of twice the negative log-likelihood with respect to the SM (corresponding to $g_{A t \bar t} = g_{H t \bar t} = 0$) for the simultaneous presence of A, $m_A = 450$ GeV, $\Gamma_A/m_A = 5.0$% and H, $m_H = 400$ GeV, $\Gamma_H/m_H = 5.0$% as a function of the coupling modifiers $g_{A t \bar t}$ and $g_{H t \bar t}$.

More…

Low-mass vector-meson production at forward rapidity in $p$$+$$p$ and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$~GeV

The PHENIX collaboration Abdulameer, N.J. ; Acharya, U. ; Adare, A. ; et al.
2025.
Inspire Record 2942761 DOI 10.17182/hepdata.165500

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured low-mass vector-meson ($ω+ρ$ and $ϕ$) production through the dimuon decay channel at forward rapidity $(1.2<|\mbox{y}|<2.2)$ in $p$$+$$p$ and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$~GeV. The low-mass vector-meson yield and nuclear-modification factor were measured as a function of the average number of participating nucleons, $\langle N_{\rm part}\rangle$, and the transverse momentum $p_T$. These results were compared with those obtained via the kaon decay channel in a similar $p_T$ range at midrapidity. The nuclear-modification factors in both rapidity regions are consistent within the uncertainties. A comparison of the $ω+ρ$ and $J/ψ$ mesons reveals that the light and heavy flavors are consistently suppressed across both $p_T$ and ${\langle}N_{\rm part}\rangle$. In contrast, the $ϕ$ meson displays a nuclear-modification factor consistent with unity, suggesting strangeness enhancement in the medium formed.

0 data tables

Search for the nonresonant and resonant production of a Higgs boson in association with an additional scalar boson in the $γγττ$ final state in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-HIG-22-012, 2025.
Inspire Record 2940190 DOI 10.17182/hepdata.158371

The results of a search for the production of two scalar bosons in final states with two photons and two tau leptons are presented. The search considers both nonresonant production of a Higgs boson pair, HH, and resonant production via a new boson X which decays either to HH or to H and a new scalar Y. The analysis uses up to 138 fb$^{-1}$ of proton-proton collision data, recorded between 2016 and 2018 by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV. No evidence for signal is found in the data. For the nonresonant production, the observed (expected) upper limit at 95% confidence level (CL) on the HH production cross section is set at 930 (740) fb, corresponding to 33 (26) times the standard model prediction. At 95% CL, HH production is observed (expected) to be excluded for values of $κ_λ$ outside the range between $-$12 ($-$9.4) and 17 (15). Observed (expected) upper limits at 95% CL for the XHH cross section are found to be within 160 to 2200 (200 to 1800) fb, depending on the mass of X. In the X $\to$ Y($γγ$)H($ττ$) search, the observed (expected) upper limits on the product of the production cross section and decay branching fractions vary between 0.059$-$1.2 fb (0.087$-$0.68 fb). For the X $\to$ Y($γγ$)H($ττ$) search the observed (expected) upper limits on the product of the production cross section and Y $to$ $γγ$ branching fraction vary between 0.69$-$15 fb (0.73$-$8.3 fb) in the low Y mass search, tightening constraints on the next-to-minimal supersymmetric standard model, and between 0.64$-$10 fb (0.70$-$7.6 fb) in the high Y mass search.

13 data tables

Observed and expected 95% CL upper limits on the nonresonant $\mathrm{HH}$ production cross section, $\sigma(\mathrm{pp} \to \mathrm{HH})$, as a function of the Higgs boson self-coupling strength modifier $\kappa_\lambda$. All Higgs boson couplings other than $\lambda$ are assumed to have the values predicted in the SM.

Observed and expected 95% CL upper limits on the nonresonant $\mathrm{HH}$ production cross section, $\sigma(\mathrm{pp} \to \mathrm{HH})$, for thirteen different BSM benchmark scenarios from [arXiv:1507.02245, arXiv:1806.05162] which consider different values of the couplings, $\kappa_\lambda$, $\kappa_t$, $c_{2g}$, $c_g$, and $c_2$ (defined in Table 1).

Observed and expected 95% CL upper limits on the cross section for the resonant production of a new spin-0 particle $\mathrm{X}^{(0)}$ which decays to Higgs boson pairs, $\sigma(\mathrm{pp} \to \mathrm{X}^{(0)} \to \mathrm{HH})$, given for different values of $m_\mathrm{X}$ in the range 260-1000 GeV.

More…

Search for nonresonant new physics signals in high-mass dilepton events produced in association with b-tagged jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-EXO-23-010, 2025.
Inspire Record 2935112 DOI 10.17182/hepdata.156189

A search for nonresonant new physics phenomena in high-mass dilepton events produced in association with b-tagged jets is performed using proton-proton collision data collected in 2016$-$2018 by the CMS experiment at the CERN LHC, at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb$^{-1}$. The analysis considers two effective field theory models with dimension-six operators; involving four-fermion contact interactions between two leptons ($\ell\ell$, electrons or muons) and b or s quarks (bb$\ell\ell$ and bs$\ell\ell$). Two lepton flavor combinations (ee and $μμ$) are required and events are classified as having 0, 1, and $\geq$2 b-tagged jets in the final state. No significant excess is observed over the standard model backgrounds. Upper limits are set on the production cross section of the new physics signals. These translate into lower limits on the energy scale $Λ$ of 6.9 to 9.0 TeV in the bb$\ell\ell$ model, depending on model parameters, and on the ratio of energy scale and effective coupling, $Λ/g_*$, of 2.0 to 2.6 TeV in the bs$\ell\ell$ model. The latter represent the most stringent limits on this model to date. Lepton flavor universality is also tested by comparing the dielectron and dimuon mass spectra for different b-tagged jet multiplicities. No significant deviation from the standard model expectation of unity is observed.

27 data tables

Signal efficiencies with Full Run 2 dimuon channel for different bbll signal scenarios

Signal efficiencies with Full Run 2 dimuon channel for different bbll (destructive interference) signal scenarios

Signal efficiencies with Full Run 2 dimuon channel in 1b final state for different bbll signal scenarios

More…

Measurement of inclusive jet cross section and substructure in $p$+$p$ collisions at $\sqrt{s_{_{NN}}}=200$ GeV

The PHENIX collaboration Abdulameer, N.J. ; Acharya, U. ; Aidala, C. ; et al.
Phys.Rev.D 111 (2025) 112008, 2025.
Inspire Record 2820229 DOI 10.17182/hepdata.158374

The jet cross-section and jet-substructure observables in $p$$+$$p$ collisions at $\sqrt{s}=200$ GeV were measured by the PHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC). Jets are reconstructed from charged-particle tracks and electromagnetic-calorimeter clusters using the anti-$k_{t}$ algorithm with a jet radius $R=0.3$ for jets with transverse momentum within $8.0<p_T<40.0$ GeV/$c$ and pseudorapidity $|η|<0.15$. Measurements include the jet cross section, as well as distributions of SoftDrop-groomed momentum fraction ($z_g$), charged-particle transverse momentum with respect to jet axis ($j_T$), and radial distributions of charged particles within jets ($r$). Also meaureed was the distribution of $ξ=-ln(z)$, where $z$ is the fraction of the jet momentum carried by the charged particle. The measurements are compared to theoretical next-to and next-to-next-to-leading-order calculatios, PYTHIA event generator, and to other existing experimental results. Indicated from these meaurements is a lower particle multiplicity in jets at RHIC energies when compared to models. Also noted are implications for future jet measurements with sPHENIX at RHIC as well as at the future Electron-Ion Collider.

0 data tables

Search for top squarks in final states with many light-flavor jets and 0, 1, or 2 charged leptons in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-SUS-23-001, 2025.
Inspire Record 2933169 DOI 10.17182/hepdata.156817

Several new physics models including versions of supersymmetry (SUSY) characterized by $R$-parity violation (RPV) or with 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 top squarks decaying to two top quarks and six additional light-flavor quarks or gluons are reported. The search employs a novel machine learning method for background estimation from control samples in data using decorrelated discriminators. The search is performed using events with 0, 1, or 2 electrons or muons in conjunction with at least six jets. No requirement is placed on the magnitude of the missing transverse momentum. The result is based on a sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV corresponding to 138 fb$^{-1}$ of integrated luminosity collected with the CMS detector at the LHC in 2016$-$2018. The data are used to determine upper limits on the top squark pair production cross section in the frameworks of RPV and stealth SUSY. Models with top squark masses less than 700 (930) GeV are excluded at 95% confidence level for RPV (stealth) SUSY scenarios.

32 data tables

Cutflows and signal efficiencies for the RPV SUSY model in the $0\ell$ channel corresponding to two values of $m_{\tilde{t}}$.

Cutflows and signal efficiencies for the Stealth SYY SUSY model in the $0\ell$ channel corresponding to two values of $m_{\tilde{t}}$.

Cutflows and signal efficiencies for the RPV SUSY model in the $1\ell$ channel corresponding to two values of $m_{\tilde{t}}$.

More…