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  1. Do algorithms for drawing graphs pass theTuringTest?That is, are their outputs indistinguishable from graphs drawn by humans? We address this question through a human-centred experiment, focusing on ‘small’ graphs, of a size for which it would be reasonable for someone to choose to draw the graph manually. Overall, we find that hand-drawn layouts can be distinguished from those generated by graph drawing algorithms, although this is not always the case for graphs drawn by force- directed or multi-dimensional scaling algorithms, making these good candidates for Turing Test success. We show that, in general, hand-drawn graphs are judged to be of higher quality than automatically generated ones, although this result varies with graph size and algorithm. 
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  2. Cosmic shear, galaxy clustering, and the abundance of massive halos each probe the large-scale structure of the Universe in complementary ways. We present cosmological constraints from the joint analysis of the three probes, building on the latest analyses of the lensing-informed abundance of clusters identified by the South Pole Telescope (SPT) and of the auto- and cross-correlation of galaxy position and weak lensing measurements ( 3 × 2 pt ) in the Dark Energy Survey (DES). We consider the cosmological correlation between the different tracers and we account for the systematic uncertainties that are shared between the large-scale lensing correlation functions and the small-scale lensing-based cluster mass calibration. Marginalized over the remaining Λ cold dark matter ( Λ CDM ) parameters (including the sum of neutrino masses) and 52 astrophysical modeling parameters, we measure Ω m = 0.300 ± 0.017 and σ 8 = 0.797 ± 0.026 . Compared to constraints from primary cosmic microwave background (CMB) anisotropies, our constraints are only 15% wider with a probability to exceed of 0.22 ( 1.2 σ ) for the two-parameter difference. We further obtain S 8 σ 8 ( Ω m / 0.3 ) 0.5 = 0.796 ± 0.013 which is lower than the measurement at the 1.6 σ level. The combined SPT cluster, DES 3 × 2 pt , and datasets mildly prefer a nonzero positive neutrino mass, with a 95% upper limit m ν < 0.25 eV on the sum of neutrino masses. Assuming a w CDM model, we constrain the dark energy equation of state parameter w = 1.1 5 0.17 + 0.23 and when combining with primary CMB anisotropies, we recover w = 1.2 0 0.09 + 0.15 , a 1.7 σ difference with a cosmological constant. The precision of our results highlights the benefits of multiwavelength multiprobe cosmology and our analysis paves the way for upcoming joint analyses of next-generation datasets. Published by the American Physical Society2025 
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    Free, publicly-accessible full text available March 1, 2026
  3. Abstract Despite the f0(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ ) meson, a tetraquark ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ q q ¯ ) exotic state, a kaon-antikaon ($${{\rm{K}}}\overline{{{\rm{K}}}}$$ K K ¯ ) molecule, or a quark-antiquark-gluon ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ q q ¯ g ) hybrid. This paper reports strong evidence that the f0(980) state is an ordinary$${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ meson, inferred from the scaling of elliptic anisotropies (v2) with the number of constituent quarks (nq), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f0(980) state is reconstructed via its dominant decay channel f0(980) →π+π, in proton-lead collisions recorded by the CMS experiment at the LHC, and itsv2is measured as a function of transverse momentum (pT). It is found that thenq= 2 ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ state) hypothesis is favored overnq= 4 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ q q ¯ or$${{\rm{K}}}\overline{{{\rm{K}}}}$$ K K ¯ states) by 7.7, 6.3, or 3.1 standard deviations in thepT< 10, 8, or 6 GeV/cranges, respectively, and overnq= 3 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ q q ¯ g hybrid state) by 3.5 standard deviations in thepT< 8 GeV/crange. This result represents the first determination of the quark content of the f0(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates. 
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    Free, publicly-accessible full text available December 1, 2026
  4. Incoherent J / ψ photoproduction in heavy ion ultraperipheral collisions (UPCs) provides a sensitive probe of localized, fluctuating gluonic structures within heavy nuclei. This Letter reports the first measurement of the photon-nucleon center-of-mass energy ( W γ N ) dependence of this process in PbPb UPCs at a nucleon-nucleon center-of-mass energy of 5.02 TeV, using 1.52 nb 1 of data recorded by the CMS experiment. The measurement covers a wide W γ N range of 40 400 GeV , probing gluons carrying a fraction x of nucleon momentum down to an unexplored regime of 6.5 × 10 5 . Compared to baseline predictions neglecting nuclear effects, the measured cross sections exhibit significantly greater suppression at lower x . Additionally, the ratio of incoherent to coherent photoproduction is found to be constant across the probed W γ N and x range, disfavoring the establishment of the black disk limit. This Letter provides critical insights into the x -dependent evolution of fluctuating gluonic structures within nuclei and calls for further advancements in theoretical models incorporating nuclear shadowing and gluon saturation. 
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    Free, publicly-accessible full text available September 1, 2026
  5. The polarization of the Λ and Λ ¯ hyperons along the beam direction has been measured in proton-lead ( p -Pb ) collisions at a center-of-mass energy per nucleon pair of 8.16 TeV. The data were obtained with the CMS detector at the LHC and correspond to an integrated luminosity of 186.0 ± 6.5 nb 1 . A significant azimuthal dependence of the hyperon polarization, characterized by the second-order Fourier sine coefficient P z , s 2 , is observed. The P z , s 2 values decrease as a function of charged particle multiplicity, but increase with transverse momentum. A hydrodynamic model that describes the observed P z , s 2 values in nucleus-nucleus collisions by introducing vorticity effects does not reproduce either the sign or the magnitude of the p -Pb results. These observations pose a challenge to the current theoretical implementation of spin polarization in heavy ion collisions and offer new insights into the origin of spin polarization in hadronic collisions at LHC energies. 
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    Free, publicly-accessible full text available September 1, 2026
  6. A search for flavor-changing neutral current interactions of the top quark ( t ) and the Higgs boson ( H ) is presented. The search is based on proton-proton collision data collected in 2016–2018 at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, and corresponding to an integrated luminosity of 138 fb 1 . Events containing a pair of leptons with the same-sign electric charge and at least one jet are considered. The results are used to constrain the branching fraction ( B ) of the top quark decaying to a Higgs boson and an up ( u ) or charm ( c ) quark. No significant excess above the estimated background was found. The observed (expected) upper limits at a 95% confidence level are found to be 0.072% (0.059%) for B ( t H u ) and 0.043% (0.062%) for B ( t H c ) . These results are combined with two other searches performed by the CMS Collaboration for flavor-changing neutral current interactions of top quarks and Higgs bosons in final states where the Higgs boson decays to either a pair of photons or a pair of bottom quarks. The resulting observed (expected) upper limits at the 95% confidence level are 0.019% (0.027%) for B ( t H u ) and 0.037% (0.035%) for B ( t H c )
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    Free, publicly-accessible full text available August 1, 2026
  7. Bound states of charm and anticharm quarks, known as charmonia, have a rich spectroscopic structure that can be used to probe the dynamics of hadron production in high-energy hadron collisions. Here, the cross section ratio of excited ( ψ ( 2 S ) ) and ground state ( J / ψ ) vector mesons is measured as a function of the charged-particle multiplicity in proton-lead ( p Pb ) collisions at a center-of-mass (CM) energy per nucleon pair of 8.16 TeV. The data corresponding to an integrated luminosity of 175 nb 1 were collected using the CMS detector. The ratio is measured separately for prompt and nonprompt charmonia in the transverse momentum range 6.5 < p T < 30 GeV and in four rapidity ranges spanning 2.865 < y CM < 1.935 . For the first time, a statistically significant multiplicity dependence of the prompt cross section ratio is observed in proton-nucleus collisions. There is no clear rapidity dependence in the ratio. The prompt measurements are compared with a theoretical model which includes interactions with nearby particles during the evolution of the system. These results provide additional constraints on hadronization models of heavy quarks in nuclear collisions. 
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    Free, publicly-accessible full text available August 1, 2026
  8. The first search for a heavy neutral spin-1 gauge boson ( Z ) with nonuniversal fermion couplings produced via vector boson fusion processes and decaying to tau leptons or W bosons is presented. The analysis is performed using LHC data at s = 13 TeV , collected from 2016 to 2018 with the CMS experiment and corresponding to an integrated luminosity of 138 fb 1 . The data are consistent with the standard model predictions. Upper limits are set on the product of the cross section for production of the Z boson and its branching fraction to τ τ or W W . The presence of a Z boson decaying to τ + τ ( W + W ) is excluded for masses up to 2.45(1.60) TeV, depending on the Z boson coupling to standard model weak bosons, and assuming a Z τ + τ ( W + W ) branching fraction of 50%. 
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    Free, publicly-accessible full text available August 1, 2026
  9. Charged hadron elliptic anisotropies ( v 2 ) are presented over a wide transverse momentum ( p T ) range for proton-lead ( p Pb ) and lead-lead (PbPb) collisions at nucleon-nucleon center-of-mass energies of 8.16 and 5.02 TeV, respectively. The data were recorded by the CMS experiment and correspond to integrated luminosities of 186 and 0.607 nb 1 for the p Pb and PbPb systems, respectively. A four-particle cumulant analysis is performed using subevents separated in pseudorapidity to effectively suppress noncollective effects. At high p T ( p T > 8 GeV ), significant positive v 2 values that are similar between p Pb and PbPb collisions at comparable charged particle multiplicities are observed. This observation suggests a common origin for the multiparticle collectivity for high- p T particles in the two systems. 
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    Free, publicly-accessible full text available August 1, 2026