pith. machine review for the scientific record. sign in

arxiv: 2604.19495 · v1 · submitted 2026-04-21 · ✦ hep-ex

Recognition: unknown

Search for quantum black holes in lepton+jet final states using proton-proton collisions at sqrt{s}=13.6 TeV with the ATLAS detector

ATLAS Collaboration

Pith reviewed 2026-05-10 01:04 UTC · model grok-4.3

classification ✦ hep-ex
keywords quantum black holeslepton jet eventshigh mass searchescross section upper limitsbackground modelingproton collisionsnew physics limits
0
0 comments X

The pith

No significant excess above expected background is observed in high-mass lepton plus jet events, setting new upper limits on quantum black hole production reaching 9.4 TeV.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper analyzes data from proton collisions at a center of mass energy of 13.6 TeV to search for quantum black holes that would appear as a lepton and a jet with very high combined mass. The observed events match the expectations from ordinary particle processes with no extra events seen. Therefore, the production rate of quantum black holes must be lower than the calculated upper limits, which now cover masses up to 9.4 TeV thanks to the higher energy collisions compared to earlier runs. Sympathetic readers would care because this narrows down the possible existence of such exotic objects that could arise in theories attempting to explain gravity at tiny scales.

Core claim

Using proton-proton collision data corresponding to an integrated luminosity of 164 inverse femtobarns at a center-of-mass energy of 13.6 TeV, the search for quantum black holes in electron plus jet or muon plus jet final states with high invariant mass observes no significant excess above the Standard Model background. Consequently, upper limits at the 95 percent confidence level are set on the production cross-section times branching ratio in several benchmark models, with the mass scale excluded reaching 9.4 TeV. These limits are the strongest exclusion limits to date on quantum black hole production.

What carries the argument

The invariant mass spectrum of lepton plus jet pairs at high values, serving as the observable to test for deviations from background expectations and to set limits on quantum black hole signals.

If this is right

  • Quantum black hole production is excluded at 95 percent confidence level for masses up to 9.4 TeV in the benchmark models considered.
  • The higher collision energy increases the expected signal cross section by up to an order of magnitude at the highest masses.
  • The non-observation provides the tightest constraints currently available on these hypothetical particles.
  • These results can inform the design of future searches with additional data or different final states.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Higher energy colliders would further extend the mass reach for searching quantum black holes if they exist.
  • Other experimental channels, such as those without leptons, could be used to cross-check or strengthen these limits.
  • The method of using small energy upgrades to boost high-mass sensitivity could apply to searches for other heavy new particles.

Load-bearing premise

The Standard Model background must be accurately modeled in the high-mass lepton plus jet region, and the signal simulations for the quantum black hole benchmark models must correctly predict the acceptance and cross sections.

What would settle it

A clear excess of events in the highest invariant mass bins compared to the predicted background would falsify the no-excess observation and potentially indicate quantum black hole production.

read the original abstract

A search for quantum black holes in electron+jet or muon+jet final states with high invariant mass is performed. The analysis uses data from $\sqrt{s}=13.6~\textrm{TeV}$ $pp$ collisions recorded by the ATLAS detector between 2022 and 2024 during Run~3 of the Large Hadron Collider, corresponding to an integrated luminosity of $164~\mathrm{fb}^{-1}$. This search is strongly motivated by a dramatic increase of the production cross-section by up to an order of magnitude for the highest masses considered, thanks to the small increase of $0.6~\textrm{TeV}$ in centre-of-mass energy between Run~2 and Run~3. No significant excess above the Standard Model background is observed, and 95\% CL upper limits are set on the production cross-section times branching ratio in several benchmark models, reaching a mass scale of $9.4~\textrm{TeV}$. These represent the strongest exclusion limits to date on quantum black hole production.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 1 minor

Summary. The paper reports a search for quantum black holes decaying into high-mass lepton+jet final states (electron+jet or muon+jet) using 164 fb^{-1} of proton-proton collision data at 13.6 TeV recorded by ATLAS during Run 3 (2022-2024). No significant excess above the Standard Model background is observed, and 95% CL upper limits are placed on the production cross-section times branching ratio for several benchmark quantum black hole models, reaching an excluded mass scale of 9.4 TeV. These are presented as the strongest limits to date, benefiting from the increased center-of-mass energy relative to Run 2.

Significance. If the result holds, the work delivers the tightest LHC constraints on quantum black hole production to date. The modest 0.6 TeV increase in sqrt(s) produces up to an order-of-magnitude rise in expected signal cross-section at the highest masses considered, enabling meaningfully stronger exclusions with the new dataset. This null result supplies useful guidance for models of quantum gravity and large extra dimensions.

minor comments (1)
  1. The abstract states the integrated luminosity as 164 fb^{-1} but does not quote the uncertainty; adding this (standard for ATLAS papers) would improve completeness.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive evaluation of our manuscript and their recommendation to accept the paper. No major comments were raised in the report.

Circularity Check

0 steps flagged

No significant circularity detected

full rationale

The paper reports a standard experimental search: observed data in high-mass lepton+jet events are compared directly to simulated Standard Model backgrounds and to simulated quantum black hole signals. Upper limits at 95% CL are extracted from this comparison using standard statistical procedures. No equation or step reduces a claimed prediction or limit to a parameter that was itself fitted from the same dataset; the cross-section increase with energy is an external physical input, not an internal fit. The analysis chain is therefore self-contained against external benchmarks.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on standard assumptions about background modeling and signal simulation rather than new free parameters or invented entities.

axioms (1)
  • domain assumption Standard Model background processes are accurately modeled by simulation and data-driven methods in the high-mass lepton+jet region.
    The claim of no significant excess depends on this modeling being correct.

pith-pipeline@v0.9.0 · 5481 in / 1437 out tokens · 76862 ms · 2026-05-10T01:04:29.379853+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

63 extracted references · 59 canonical work pages · 10 internal anchors

  1. [1]

    Arkani-Hamed, S

    N. Arkani-Hamed, S. Dimopoulos and G. Dvali, The hierarchy problem and new dimensions at a millimeter, Phys. Lett. B429(1998) 263, arXiv:hep-ph/9803315

  2. [2]

    Antoniadis, N

    I. Antoniadis, N. Arkani-Hamed, S. Dimopoulos and G. Dvali, New dimensions at a millimeter to a Fermi and superstrings at a TeV, Phys. Lett. B436(1998) 257, arXiv:hep-ph/9804398

  3. [3]

    A Large Mass Hierarchy from a Small Extra Dimension

    L. Randall and R. Sundrum,Large mass hierarchy from a small extra dimension, Phys. Rev. Lett.83(1999) 3370, arXiv:hep-ph/9905221

  4. [4]

    D. M. Gingrich,Quantum black holes with charge, color, and spin at the LHC, J. Phys. G37(2010) 105008, arXiv:0912.0826 [hep-ph]

  5. [5]

    Meade and L

    P. Meade and L. Randall,Black Holes and Quantum Gravity at the LHC, JHEP05(2008) 003, arXiv:0708.3017 [hep-ph]

  6. [6]

    Calmet, W

    X. Calmet, W. Gong and S. D. H. Hsu,Colorful quantum black holes at the LHC, Phys. Lett. B668(2008) 20, arXiv:0806.4605 [hep-ph]

  7. [7]

    D. M. Gingrich,Monte Carlo event generator for black hole production and decay in proton-proton collisions — QBH version 1.02, Comput. Phys. Commun.181(2010) 1917, arXiv:0911.5370 [hep-ph]

  8. [8]

    D. M. Gingrich,Collider searches for non-perturbative low-scale gravity states, Int. J. Mod. Phys. A30(2015) 1530061, arXiv:1509.07180 [hep-ph]

  9. [9]

    L. A. Anchordoqui, J. L. Feng, H. Goldberg and A. D. Shapere, Black holes from cosmic rays: Probes of extra dimensions and new limits on TeV-scale gravity, Phys. Rev. D65(2002) 124027, arXiv:hep-ph/0112247

  10. [10]

    ATLAS Collaboration,Search for strong gravity in multijet final states produced in pp collisions at√𝑠=13 TeV using the ATLAS detector at the LHC, JHEP03(2016) 026, arXiv:1512.02586 [hep-ex]

  11. [11]

    ATLAS Collaboration,Search for heavy particles decaying into top-quark pairs using lepton-plus-jets events in proton–proton collisions at√𝑠=13TeV with the ATLAS detector, Eur. Phys. J. C78(2018) 565, arXiv:1804.10823 [hep-ex]

  12. [12]

    CMS Collaboration,Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at√𝑠=13 TeV, Phys. Lett. B774(2017) 279, arXiv:1705.01403 [hep-ex]

  13. [13]

    CMS Collaboration,Search for black holes and sphalerons in high-multiplicity final states in proton-proton collisions at√𝑠=13TeV, JHEP11(2018) 042, arXiv:1805.06013 [hep-ex]

  14. [14]

    ATLAS Collaboration,Search for quantum black hole production in lepton+jet final states using proton-proton collisions at√𝑠 = 13 TeV with the ATLAS detector, Phys. Rev. D109(2024) 032010, arXiv:2307.14967 [hep-ex]

  15. [15]

    ATLAS Collaboration,Search for Quantum Black Hole Production in High-Invariant-Mass Lepton+Jet Final States Using𝑝 𝑝Collisions at√𝑠=8 TeV and the ATLAS Detector, Phys. Rev. Lett.112(2014) 091804, arXiv:1311.2006 [hep-ex]. 14

  16. [16]

    ATLAS Collaboration,Search for new phenomena in dijet mass and angular distributions from𝑝 𝑝 collisions at√𝑠=13 TeV with the ATLAS detector, Phys. Lett. B754(2016) 302, arXiv:1512.01530 [hep-ex]

  17. [17]

    ATLAS Collaboration,Search for new phenomena in different-flavour high-mass dilepton final states in pp collisions at√𝑠=13Tev with the ATLAS detector, Eur. Phys. J. C76(2016) 541, arXiv:1607.08079 [hep-ex]

  18. [18]

    ATLAS Collaboration,Search for new resonances in mass distributions of jet pairs using 139 fb−1 of𝑝 𝑝collisions at √𝑠=13TeV with the ATLAS detector, JHEP03(2020) 145, arXiv:1910.08447 [hep-ex]

  19. [19]

    ATLAS Collaboration,Search for new phenomena in photon+jet events collected in proton–proton collisions at√𝑠= 8 TeV with the ATLAS detector, Phys. Lett. B728(2014) 562, arXiv:1309.3230 [hep-ex]

  20. [20]

    ATLAS Collaboration,Search for new phenomena with photon+jet events in proton-proton collisions at√𝑠=13TeV with the ATLAS detector, JHEP03(2016) 041, arXiv:1512.05910 [hep-ex]

  21. [21]

    ATLAS Collaboration,Search for new phenomena in high-mass final states with a photon and a jet from𝑝 𝑝collisions at √𝑠= 13 TeV with the ATLAS detector, Eur. Phys. J. C78(2018) 102, arXiv:1709.10440 [hep-ex]

  22. [22]

    CMS Collaboration, Search for new physics with dijet angular distributions in proton-proton collisions at√𝑠=13TeV, JHEP07(2017) 013, arXiv:1703.09986 [hep-ex]

  23. [23]

    CMS Collaboration,Search for lepton-flavor violating decays of heavy resonances and quantum black holes to e𝜇final states in proton-proton collisions at√𝑠=13TeV, JHEP04(2018) 073, arXiv:1802.01122 [hep-ex]

  24. [24]

    CMS Collaboration,Search for heavy resonances and quantum black holes in𝑒𝜇, 𝑒𝜏, and𝜇𝜏 final states in proton–proton collisions at√𝑠=13TeV, JHEP05(2023) 227, arXiv:2205.06709 [hep-ex]

  25. [25]

    CMS Collaboration,Search for resonances in events with photon and jet final states in proton-proton collisions at√𝑠= 13 TeV, JHEP12(2023) 189, arXiv:2305.07998 [hep-ex]

  26. [26]

    ATLAS Collaboration,Search for resonant leptoquark production via lepton-jet signatures in𝑝 𝑝 collisions at√𝑠=13TeV and √𝑠=13.6TeV with the ATLAS detector, JHEP12(2025) 180, arXiv:2507.03650 [hep-ex]

  27. [27]

    ATLAS Collaboration,The ATLAS Experiment at the CERN Large Hadron Collider, JINST3(2008) S08003

  28. [28]

    ATLAS Collaboration,The ATLAS experiment at the CERN Large Hadron Collider: a description of the detector configuration for Run 3, JINST19(2024) P05063, arXiv:2305.16623 [physics.ins-det]

  29. [29]

    Avoni et al.,The new LUCID-2 detector for luminosity measurement and monitoring in ATLAS, JINST13(2018) P07017

    G. Avoni et al.,The new LUCID-2 detector for luminosity measurement and monitoring in ATLAS, JINST13(2018) P07017

  30. [30]

    ATLAS Collaboration,Performance of the ATLAS trigger system in 2015, Eur. Phys. J. C77(2017) 317, arXiv:1611.09661 [hep-ex]. 15

  31. [31]

    ATLAS Collaboration,The ATLAS trigger system for LHC Run 3 and trigger performance in 2022, JINST19(2024) P06029, arXiv:2401.06630 [hep-ex]

  32. [32]

    ATLAS Collaboration,Software and computing for Run 3 of the ATLAS experiment at the LHC, Eur. Phys. J. C85(2025) 234, arXiv:2404.06335 [hep-ex], Erratum: Eur. Phys. J. C85(2025) 907

  33. [33]

    ATLAS Collaboration,ATLAS data quality operations and performance for 2015–2018 data-taking, JINST15(2020) P04003, arXiv:1911.04632 [physics.ins-det]

  34. [34]

    A comprehensive guide to the physics and usage of PYTHIA 8.3

    C. Bierlich et al.,A comprehensive guide to the physics and usage of PYTHIA 8.3, SciPost Phys. Codebases (2022) 8, arXiv:2203.11601 [hep-ph]

  35. [35]

    Pumplin et al., New Generation of Parton Distributions with Uncertainties from Global QCD Analysis, JHEP07(2002) 012, arXiv:hep-ph/0201195

    J. Pumplin et al., New Generation of Parton Distributions with Uncertainties from Global QCD Analysis, JHEP07(2002) 012, arXiv:hep-ph/0201195

  36. [36]

    Bothmann et al.,Event generation with Sherpa 2.2, SciPost Phys.7(2019) 034, arXiv:1905.09127 [hep-ph]

    E. Bothmann et al.,Event generation with Sherpa 2.2, SciPost Phys.7(2019) 034, arXiv:1905.09127 [hep-ph]

  37. [37]

    NNPDF Collaboration, R. D. Ball et al.,Parton distributions for the LHC run II, JHEP04(2015) 040, arXiv:1410.8849 [hep-ph]

  38. [38]

    A Positive-Weight Next-to-Leading-Order Monte Carlo for Heavy Flavour Hadroproduction

    S. Frixione, G. Ridolfi and P. Nason, A positive-weight next-to-leading-order Monte Carlo for heavy flavour hadroproduction, JHEP09(2007) 126, arXiv:0707.3088 [hep-ph]

  39. [39]

    A New Method for Combining NLO QCD with Shower Monte Carlo Algorithms

    P. Nason,A new method for combining NLO QCD with shower Monte Carlo algorithms, JHEP11(2004) 040, arXiv:hep-ph/0409146

  40. [40]

    Matching NLO QCD computations with Parton Shower simulations: the POWHEG method

    S. Frixione, P. Nason and C. Oleari, Matching NLO QCD computations with parton shower simulations: the POWHEG method, JHEP11(2007) 070, arXiv:0709.2092 [hep-ph]

  41. [41]

    A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX

    S. Alioli, P. Nason, C. Oleari and E. Re,A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX, JHEP06(2010) 043, arXiv:1002.2581 [hep-ph]

  42. [42]

    J. Alwall et al.,The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations, JHEP07(2014) 079, arXiv:1405.0301 [hep-ph]

  43. [43]

    An Introduction to PYTHIA 8.2

    T. Sjöstrand et al.,An introduction to PYTHIA 8.2, Comput. Phys. Commun.191(2015) 159, arXiv:1410.3012 [hep-ph]

  44. [44]

    D. J. Lange,The EvtGen particle decay simulation package, Nucl. Instrum. Meth. A462(2001) 152

  45. [45]

    ATLAS Collaboration,The ATLAS Simulation Infrastructure, Eur. Phys. J. C70(2010) 823, arXiv:1005.4568 [physics.ins-det]

  46. [46]

    Agostinelli et al.,Geant4– a simulation toolkit, Nucl

    S. Agostinelli et al.,Geant4– a simulation toolkit, Nucl. Instrum. Meth. A506(2003) 250

  47. [47]

    ATLAS Collaboration,Emulating the impact of additional proton–proton interactions in the ATLAS simulation by presampling sets of inelastic Monte Carlo events, Comput. Softw. Big Sci.6(2022) 3, arXiv:2102.09495 [hep-ex]. 16

  48. [48]

    Parton Ladder Splitting and the Rapidity Dependence of Transverse Momentum Spectra in Deuteron-Gold Collisions at RHIC

    K. Werner, F.-M. Liu and T. Pierog, Parton ladder splitting and the rapidity dependence of transverse momentum spectra in deuteron–gold collisions at the BNL Relativistic Heavy Ion Collider, Phys. Rev. C74(2006) 044902, arXiv:hep-ph/0506232

  49. [49]

    ATLAS Collaboration,Electron and photon efficiencies in LHC Run 2 with the ATLAS experiment, JHEP05(2024) 162, arXiv:2308.13362 [hep-ex]

  50. [50]

    ATLAS Collaboration, Electron and photon energy calibration with the ATLAS detector using LHC Run 2 data, JINST19(2024) P02009, arXiv:2309.05471 [hep-ex]

  51. [51]

    ATLAS Collaboration,Muon reconstruction and identification efficiency in ATLAS using the full Run 2𝑝 𝑝collision data set at√𝑠=13TeV, Eur. Phys. J. C81(2021) 578, arXiv:2012.00578 [hep-ex]

  52. [52]

    ATLAS Collaboration, Jet reconstruction and performance using particle flow with the ATLAS Detector, Eur. Phys. J. C77(2017) 466, arXiv:1703.10485 [hep-ex]

  53. [53]

    The anti-k_t jet clustering algorithm

    M. Cacciari, G. P. Salam and G. Soyez,The anti-𝑘𝑡 jet clustering algorithm, JHEP04(2008) 063, arXiv:0802.1189 [hep-ph]

  54. [54]

    FastJet user manual

    M. Cacciari, G. P. Salam and G. Soyez,FastJet user manual, Eur. Phys. J. C72(2012) 1896, arXiv:1111.6097 [hep-ph]

  55. [55]

    ATLAS Collaboration,The performance of missing transverse momentum reconstruction and its significance with the ATLAS detector using140fb−1 of √𝑠=13TeV𝑝 𝑝collisions, Eur. Phys. J. C85(2025) 606, arXiv:2402.05858 [hep-ex]

  56. [56]

    ATLAS Collaboration,Performance of pile-up mitigation techniques for jets in𝑝 𝑝collisions at√𝑠=8TeV using the ATLAS detector, Eur. Phys. J. C76(2016) 581, arXiv:1510.03823 [hep-ex]

  57. [57]

    ATLAS Collaboration,Vertex Reconstruction Performance of the ATLAS Detector at√𝑠=13TeV , ATL-PHYS-PUB-2015-026, 2015,url:https://cds.cern.ch/record/2037717

  58. [58]

    ATLAS Collaboration, Tools for estimating fake/non-prompt lepton backgrounds with the ATLAS detector at the LHC, JINST18(2023) T11004, arXiv:2211.16178 [hep-ex]

  59. [59]

    ATLAS Collaboration,Electron and photon performance measurements with the ATLAS detector using the 2015–2017 LHC proton–proton collision data, JINST14(2019) P12006, arXiv:1908.00005 [hep-ex]

  60. [60]

    ATLAS Collaboration,Jet energy scale and resolution measured in proton–proton collisions at√𝑠=13TeV with the ATLAS detector, Eur. Phys. J. C81(2021) 689, arXiv:2007.02645 [hep-ex]

  61. [61]

    ATLAS Collaboration,Preliminary luminosity calibration of the ATLAS13.6TeV data recorded in 2024 and combination with the 2022 and 2023 measurements, ATL-DAPR-PUB-2025-001, 2025, url:https://cds.cern.ch/record/2948582

  62. [62]

    Asymptotic formulae for likelihood-based tests of new physics

    G. Cowan, K. Cranmer, E. Gross and O. Vitells, Asymptotic formulae for likelihood-based tests of new physics, Eur. Phys. J. C71(2011) 1554, arXiv:1007.1727 [physics.data-an], Erratum: Eur. Phys. J. C73(2013) 2501. 17

  63. [63]

    Demokritos

    ATLAS Collaboration,ATLAS Computing Acknowledgements, ATL-SOFT-PUB-2026-001, 2026, url:https://cds.cern.ch/record/2952666. 18 The ATLAS Collaboration G. Aad 102, E. Aakvaag 17, B. Abbott 121, S. Abdelhameed 83b, K. Abeling 54, N.J. Abicht 48, S.H. Abidi 30, M. Aboelela 44, A. Aboulhorma 36e, H. Abramowicz 154, B.S. Acharya 68a,68b,m, A. Ackermann 62a, C. ...