{"id":"6de9d696-bdbd-4c5c-baae-e4415a88907e","arxiv_id":"2610.35331","paper_version":1,"verdict":"ACCEPT","confidence":"MODERATE","novelty_score":7.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":2,"one_line_summary":"First measurement of the per-trigger near- and away-side yields (I_AA) in OO and Ne-Ne collisions at 5.36 TeV shows a modest away-side suppression consistent with, but weaker than, Pb-Pb jet quenching.","lead":"The ALICE collaboration measured jet-like two-particle correlations in oxygen-oxygen and neon-neon collisions, finding that the away-side yield is suppressed relative to proton-proton collisions in the most central oxygen collisions. This is the first such measurement in light-ion systems, and it is weaker than the suppression seen in lead-lead, consistent with, but not proof of, jet energy loss in a quark-gluon plasma.","discovery_kind":"new_application","skeptic_critique":{"model":"deepseek/deepseek-v4-flash","headline":"The OO away-side I_AA suppression and its 'consistent with jet–medium interactions' reading rest on a 1.4σ deviation that the paper's own cited refs [22,23] — including a titled 'no-quenching baseline' — argue can be produced by event-selection bias and cold-nuclear-matter effects, and no…","rationale":"The load-bearing concern is exactly the reader's weakest_assumption: the jet-quenching reading of the 1.4σ away-side suppression presumes that event-selection biases and CNM effects do not dominate, and the paper's own cited refs [22,23] provide published quantitative argument that I_AA moves below unity in OO without quenching. Because the paper presents no baseline subtraction and the statistical pull is only 1.4σ, the data cannot distinguish the quenching from the no-quenching hypothesis. However, the authors state this limitation explicitly ([b22], [b48]) and frame the claim as 'qualitatively consistent' and an open question [b7, b46], so they are not overclaiming. The measurement itself — first I_AA in OO — is a valid new data point and stands. This does not change the reader's ACCEPT verdict or MODERATE confidence; the concern bears on the interpretation, which the paper itself treats as tentative. I agree with the reader's identification of the weakest assumption, and I find no additional load-bearing technical defect (the cross-energy Pb–Pb comparison at 2.76 vs 5.36 TeV is contextual rather than central, and the ZYAM/LMTF pedestal procedure is standard and tested against pT projections in §3).","tokens_in":8561,"tokens_out":4628,"duration_ms":31628,"concrete_test":"Apply the published no-quenching baseline of ref [22] (or the selection-bias framework of ref [23]) to the exact bin 8<pT,trig<15 × 4<pT,assoc<6 GeV/c with 0–5% FT0C event selection in OO, computing the predicted I_AA against minimum-bias pp at 5.36 TeV. If the baseline reproduces I_AA below unity within the quoted 1.4σ band, the jet-quenching reading of this bin is unsupported; if the baseline predicts unity (after including the pp multiplicity trend) while the data sit below, the suppression element survives as a genuine quenching hint. A secondary check: recompute the away-side yield with the ZYAM/LMTF pedestal (v2, v3 from the template fit of §2) re-extracted using the ref [22] geometry, to confirm the away-side deficit is not a pedestal-subtraction artifact.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim is that away-side I_AA falls below unity in 0–5% OO (1.4σ in the 8<pT,trig<15 × 4<pT,assoc<6 GeV/c bin, §3), read as 'qualitatively consistent with jet–medium interactions' [b46]. For that reading to survive, event-selection biases and cold-nuclear-matter (CNM) effects must not dominate the deviation. The paper itself cites the literature that directly challenges this: ref [22] (Gebhard, Mazeliauskas, Takacs, JHEP 04 (2025) 034) is titled 'No-quenching baseline for energy loss signals in oxygen-oxygen collisions', and ref [23] (Park et al., PRC 112 (2025) 064916) quantifies selection-bias effects on high-pT yields and correlations in OO. Both are published, quantitative arguments that I_AA-type observables move away from unity in OO without any parton energy loss. The paper neither subtracts nor quantifies this baseline, and at 1.4σ the data are fully consistent with the no-quenching hypothesis as well as with the quenching hypothesis. The limitation is acknowledged explicitly ([b22], [b48]) and honestly, so the measurement itself stands as a first data point; but the interpretive element — the only physically novel content — cannot discriminate between the two hypotheses on the shown data. The suppression is a not-ruled-out hypothesis, not a supported observation.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek/deepseek-v4-flash","summary":"This proceedings contribution presents per-trigger dihadron correlation measurements in OO and Ne–Ne collisions at sqrt(s_NN) = 5.36 TeV recorded with ALICE. Its new results are the first measurements of the per-trigger associated-yield ratio I_AA in OO collisions (near and away side) and of the near-side I_AA in Ne–Ne collisions, referenced to minimum-bias pp collisions at the same energy via Eq. (2). The central observations are a low-pT enhancement of both sides and a decrease of I_AA toward or below unity at higher pT, with the away-side falling below unity by 1.4 sigma in a single bin (8 < pT,trig < 15 x 4 < pT,assoc < 6 GeV/c at 0–5%, Section 3). The authors read this as qualitatively consistent with jet–medium interactions, weaker than in central Pb–Pb, while stating three times (abstract, Section 1, Section 4) that event-selection biases and cold-nuclear-matter effects can also move I_AA away from unity and are not addressed in this analysis. Systematic uncertainties are treated with Barlow-criterion filtering (Section 2). The multiplicity-dependent near-side width results are attributed to Ref. [21] and summarized rather than re-derived.","tokens_in":9047,"tokens_out":13872,"duration_ms":122857,"significance":"The measurement is a legitimate first data point in an unexplored corner of the system-size landscape: it is the first I_AA in OO collisions at the LHC and the first near-side I_AA in Ne–Ne, in a system class that sits between the 'no clear evidence' regime of pp/p–Pb and the strongly quenched Pb–Pb regime. Procedural strengths deserve explicit credit: the I_AA ratio uses an external minimum-bias pp anchor at the same nucleon–nucleon energy and is therefore not fitted; the systematic handling with the Barlow criterion is conservative; the near-side result is cross-checked between the Delta-eta and Delta-phi projections; and the authors explicitly flag the two confounds (selection bias and cold-nuclear-matter effects, refs [22,23]) that any quenching interpretation must face. The value of the paper is the measurement plus an honest statement of its ambiguity; its interpretive content is modest and, as discussed below, needs a wording correction to match its statistical weight.","major_comments":[{"comment":"The interpretive claim 'The observation of high-pT yield suppression via away-side I_AA<1 in OO collisions is qualitatively consistent with jet–medium interactions' (Section 4; abstract) rests on a single 1.4-sigma deviation in one bin (8 < pT,trig < 15 x 4 < pT,assoc < 6 GeV/c at 0–5%). The paper's own refs [22] and [23] are quantitative no-quenching baselines that can move I_AA below unity in OO through event-selection bias and cold-nuclear-matter effects, and the paper neither states nor bounds their predicted magnitude in exactly this bin. As written, the data are equally compatible with the quenching and no-quenching hypotheses, and the summary sentence overstates the discriminating power of the measurement. I recommend rewording to state explicitly that the away-side deviation is statistically weak (1.4 sigma) and is consistent both with jet–medium interactions and with the refs [22,23] baselines; if a one-sentence quantitative comparison of the [22,23] baseline with the measured deviation in this bin can be added without new analysis, it would materially strengthen the contribution.","section":"Section 3–4 and abstract","authors_acknowledge":"Insmallsystems,however,cold-nuclear-mattereffectsandbiasesrelated totheevent-activityselectioncanalsomove𝐼 AAawayfromunity[22,23],soacarefulinterpretation is required.","authors_acknowledge_p":0.72},{"comment":"The away-side yield, which carries the only novel interpretive content, is extracted from the Delta-phi projection after subtracting a ZYAM pedestal plus a v2,v3 flow term. ZYAM is known to over-subtract the background when the away-side jet contributes near the correlation minimum, i.e., precisely when the away-side is broad and suppressed as in central collisions; this bias direction coincides with the claimed I_AA < 1. The systematic variation of the pedestal with Barlow filtering covers part of this sensitivity, but the paper does not report how large the pedestal-induced spread in the away-side I_AA is relative to the 1.4-sigma deviation, nor whether the ZYAM minimum assumption was tested in central OO. Note that the near-side cross-check between the Delta-eta and Delta-phi projections does not constrain this, because the away-side exists only in the Delta-phi projection. Please add a sentence quantifying the pedestal sensitivity of the away-side bin that drives the conclusion.","section":"Section 2, ZYAM pedestal","authors_acknowledge":null,"authors_acknowledge_p":null}],"minor_comments":[{"comment":"Specify whether the quoted 1.4-sigma deviation is statistical only, systematic only, or statistical and systematic combined in quadrature; the text is ambiguous on this point.","section":"Section 3","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The flow term P(Delta-phi) includes only v2 and v3; higher-order harmonics, notably v4, can contribute to the long-range background at a level comparable to the claimed deviation, so state the check used or the reason these are negligible.","section":"Section 2","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The captions do not state whether the error bars include systematic uncertainties, and the results are shown only graphically; a small table of the I_AA values with total uncertainties for the quoted bins (especially the 8–15 x 4–6 GeV/c away-side point) would let the reader verify the 1.4-sigma statement.","section":"Figures 1–2","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The multiplicity-dependent width modification is presented in the abstract as a result of this contribution, but Section 1 states these results are already reported in Ref. [21] and are not repeated; the abstract should attribute the width results to Ref. [21] so the new versus previously-reported split is clear to the reader.","section":"Abstract and Section 1","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The Pb–Pb comparison uses I_AA at sqrt(s_NN) = 2.76 TeV while the OO and Ne–Ne data are at 5.36 TeV; add one sentence noting that part of the magnitude difference relative to central Pb–Pb could in principle reflect the energy dependence of I_AA rather than system size alone.","section":"Section 3","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The event counts or integrated luminosities for the OO, Ne–Ne, and pp samples are not reported; including them would let the reader assess the statistical reach behind a 1.4-sigma single-bin statement.","section":"Section 2 and figures","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"References [16], [17], [21], and [23] are arXiv preprints or conference contributions; please add their current publication status (journal reference, 'in preparation', or proceedings) so that the introduction's use of [16,17] as evidence for suppression is unambiguous.","section":"References","authors_acknowledge":null,"authors_acknowledge_p":null}],"recommendation":"minor_revision","confidential_remarks":"This is a proceedings contribution, and I applied the proportionate bar accordingly: the measurement is honest, the limitation is stated three times, and the fixes I request are local wording changes plus one-sentence additions. My main concern is the precedent set by the summary sentence (Section 4): if the corresponding full journal paper frames this 1.4-sigma single-bin deviation as an 'observed suppression' without a quantitative comparison against the refs [22,23] no-quenching baselines, the interpretation will not survive review elsewhere; the seed of that problem is present here and should be corrected now. The abstract's attribution of the width results (from Ref. [21]) to this contribution is also a scope issue the editor may want enforced. I see no integrity problem in the analysis handling; the Barlow-criterion systematics and the external pp reference are appropriate for this stage."},"author_rebuttal":null,"desk_editor":{"model":"deepseek/deepseek-v4-flash","letter":"This is a short ALICE proceedings note reporting genuinely first I_AA measurements: near and away side in OO, near side in Ne–Ne, at 5.36 TeV against a same-energy minimum-bias pp reference. That alone makes it a useful cross-system benchmark for small-system energy-loss models. The analysis is careful for a proceedings: Barlow-criterion systematics, mixed-event correction, and a cross-check of near-side yields from the dEta and dPhi projections. The authors also do the right thing by not repeating the near-side width study already published as ref [21] and by flagging explicitly that event-selection biases and cold-nuclear-matter effects are not addressed [b22, b48]. Credit where due: the paper is honest about what it does and does not settle.\n\nThe soft spot is the one the authors themselves signpost. The only physically interesting statement — away-side I_AA below unity in 0–5% OO — sits on a 1.4σ deviation in a single bin (8 < pT,trig < 15 x 4 < pT,assoc < 6 GeV/c). Their own cited refs [22] and [23] are a titled no-quenching baseline for OO and a quantitative selection-bias study showing that high-pT yields and correlations move away from unity without parton energy loss. The paper neither subtracts nor quantifies that baseline. So the data are fully compatible with the no-quenching hypothesis and with jet–medium interactions; \"qualitatively consistent with\" is accurate as a description, but the suppression is not established. If this becomes a journal paper rather than a proceedings note, the authors should show I_AA against the [22] baseline prediction and, where possible, in event classes with smaller selection effects. The Pb–Pb comparison at 2.76 TeV also carries an unquantified energy mismatch; probably minor here, but worth a caveat.\n\nThe citation pattern is fine. Self-citation to ALICE analyses is appropriate, and including the no-quenching references is more than many such notes do. Absence of data tables and code is normal for preliminary proceedings and I would not count it against the physics.\n\nBottom line: as a first data point with an honest hedge, this deserves a serious referee and publication as preliminary proceedings. As evidence for jet quenching in OO, it does not move the needle yet. I would read it at a journal club alongside ref [22], and I would cite it only with the caveat that the interpretation is underdetermined.","headline":"First OO/Ne–Ne I_AA data are worth having, but the only interpretive claim rides on a 1.4σ deviation that the authors' own cited no-quenching baseline could explain.","tokens_in":9637,"tokens_out":3484,"would_cite":true,"duration_ms":37024,"reading_group":"yes","serious_thinker":"yes","would_accept_peer_review":true},"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek/deepseek-v4-flash","headline":"Central OO collisions show an away-side jet-yield suppression below the pp baseline, consistent with jet–medium interaction but weaker than Pb–Pb.","keywords":["dihadron correlations","per-trigger associated yield","I_AA nuclear modification","jet quenching","quark-gluon plasma","small collision systems","oxygen-oxygen collisions","neon-neon collisions"],"falsifier":"Apply the event-selection and cold-nuclear-matter corrections cited by the paper to the $8<p_{\\rm T,trig}<15$ GeV/$c$, $4<p_{\\rm T,assoc}<6$ GeV/$c$ bin in 0-5% OO: if the away-side $I_{\\rm AA}$ returns to unity within uncertainties, the jet-medium reading is falsified; if the deficit survives those corrections, the interpretation is supported.","tokens_in":10078,"feed_emoji":"⚛️","tokens_out":16000,"duration_ms":127679,"temperature":0.7,"pith_summary":"This paper tries to establish what jet-like two-particle correlations reveal in the smallest nucleus-nucleus systems at the LHC, reporting the first $I_{\\rm AA}$ measurement in oxygen-oxygen (OO) collisions at $\\sqrt{s_{\\rm NN}}=5.36$ TeV. In 0-5% central OO events the away-side per-trigger associated yield drops below the minimum-bias pp reference, with a 1.4$\\sigma$ deficit in the $8<p_{\\rm T,trig}<15$ GeV/$c$, $4<p_{\\rm T,assoc}<6$ GeV/$c$ bin, while both sides show an enhancement at low associated momentum. The authors argue this pattern is qualitatively consistent with jet-medium interactions, but weaker than central Pb-Pb; on the near side central OO looks like peripheral Pb-Pb. Ne-Ne collisions, measured on the near side only, are compatible with OO. The paper is explicit that event-selection biases and cold-nuclear-matter effects could also move $I_{\\rm AA}$ away from unity and are not yet excluded.","feed_headline":"First oxygen–oxygen jet correlations show away-side suppression","feed_subtitle":"A 1.4-sigma dip below the pp baseline points to jet–medium effects, while biases and cold-nuclear effects still compete.","key_machinery":"The load-bearing object is $I_{\\rm AA}$, the per-trigger normalized relative yield: the ratio of the near-side or away-side associated yield in an AA system to the same yield in minimum-bias pp collisions, computed from the azimuthal projection of a mixed-event corrected same-event correlation function. The zero-yield-at-minimum pedestal and the long-range anisotropic-flow component are subtracted with a low-multiplicity template fit, so what remains is treated as the jet-like part of the correlation. $I_{\\rm AA}$ carries the argument because away-side values below unity are the proposed signature of medium-modified fragmentation, while the rise at low $p_{\\rm T}$ on both sides is the proposed signature of soft-fragment redistribution.","core_discovery":"The central claim is that OO collisions at $\\sqrt{s_{\\rm NN}}=5.36$ TeV show the first hint of jet-medium modification in the per-trigger relative yield $I_{\\rm AA}$: the away-side yield falls below unity relative to pp in central events, the low-$p_{\\rm T}$ yield is enhanced on both sides, and the pattern is weaker than the corresponding Pb-Pb suppression. The paper treats this as qualitatively consistent with jet-medium interactions, not as a definitive observation, and it explicitly leaves open the possibility that event-selection biases or cold-nuclear-matter effects contribute. On the near side, 0-5% OO is compatible with 60-90% peripheral Pb-Pb in matched $p_{\\rm T}$ bins, while central Pb-Pb shows both a stronger low-$p_{\\rm T}$ enhancement and a stronger high-$p_{\\rm T}$ away-side suppression.","pith_inferences":["Editorial inference: the comparison to Pb-Pb uses data at $\\sqrt{s_{\\rm NN}}=2.76$ TeV, while OO and Ne-Ne are at 5.36 TeV, so part of the difference in magnitude could reflect the energy dependence of the pp reference rather than system size.","Editorial inference: because 0-5% centrality is selected by forward multiplicity, the sample could be biased toward events with early hard activity; applying the selection-bias corrections the paper cites directly to these $p_{\\rm T}$ bins would show whether the 1.4$\\sigma$ deficit survives.","Editorial inference: the unmeasured Ne-Ne away side is a testable prediction of the paper's reading; if the OO suppression is a genuine medium effect, Ne-Ne away-side $I_{\\rm AA}$ should show a similar or intermediate suppression once statistics allow it.","Editorial inference: the near-side peak broadening and the low-$p_{\\rm T}$ $I_{\\rm AA}$ enhancement may be two views of the same soft-fragment redistribution, a connection that bin-by-bin correlation of the two observables could test."],"forward_implications":["The OO $I_{\\rm AA}$ points become a benchmark that parton energy-loss models must reproduce: the same models have to give near-side yields matching peripheral Pb-Pb while keeping away-side suppression weaker than central Pb-Pb.","The low-$p_{\\rm T}$ enhancement on both sides, combined with the previously reported near-side peak broadening, constrains how much jet energy is redistributed to soft fragments in small collision systems.","A higher-statistics run, or reconstructed-jet measurements in the same systems, would determine whether the 1.4$\\sigma$ away-side deficit grows into a decisive signal or reverts toward unity after bias corrections.","If the interpretation holds, OO would be the smallest collision system at the LHC with a jet-medium-like correlation signature, narrowing the size range in which quark-gluon-plasma-like behavior must be explained."],"supporting_citations":[{"why":"Supplies the central Pb-Pb comparison, showing the stronger away-side suppression against which the OO result is judged.","marker":"[9]"},{"why":"Provides the OO and Ne-Ne event-selection criteria and the anisotropic-flow evidence that frame the analysis.","marker":"[14]"},{"why":"Provides independent evidence for parton energy loss in OO that motivates reading the yield deficit as a jet-medium effect.","marker":"[16]"},{"why":"Supplies the per-trigger normalized correlation function method used to construct the jet-like yields.","marker":"[20]"},{"why":"Reports the near-side peak broadening and model comparisons in pO, OO, and Ne-Ne that this contribution extends.","marker":"[21]"},{"why":"Provides a no-quenching baseline calculation for OO showing that cold-nuclear-matter effects can shift the relative yield away from unity.","marker":"[22]"},{"why":"Quantifies event-activity selection biases on high-transverse-momentum yields and correlations in OO, the alternative explanation left open by the paper.","marker":"[23]"}],"fun_headline_variants":["First OO jet correlations hint at away-side suppression","Oxygen collisions show weak jet-medium signal in dihadrons","OO data: away-side yield dip suggests jet quenching","First light-ion jet correlations reveal possible medium effect","Oxygen-oxygen collisions: subtle jet suppression seen"],"cache_read_input_tokens":0,"weakest_assumption_plain":"The interpretation of the away-side $I_{\\rm AA}<1$ as a jet-medium effect assumes that event-selection biases and cold-nuclear-matter effects do not dominate the 1.4$\\sigma$ deficit, and this analysis does not subtract or quantify those contributions.","fun_headline_variants_meta":{"raw":{"variants":["First OO jet correlations hint at away-side 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cited by the paper to the $8<p_{\\rm T,trig}<15$ GeV/$c$, $4<p_{\\rm T,assoc}<6$ GeV/$c$ bin in 0-5% OO: if the away-side $I_{\\rm AA}$ returns to unity within uncertainties, the jet-medium reading is falsified; if the deficit survives those corrections, the interpretation is supported.","supporting_citations":[{"cited_title":"Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at $\\sqrt{s_{\\rm NN}}$ = 2.76 TeV","cited_arxiv_id":"1110.0121","evidence_quote":"Supplies the central Pb-Pb comparison, showing the stronger away-side suppression against which the OO result is judged."},{"cited_title":"Evidence of nuclear geometry-driven anisotropic flow in OO and Ne$-$Ne collisions at $\\mathbf{\\sqrt{{\\textit s}_{\\rm\\mathbf {NN}}}}$ = 5.36 TeV","cited_arxiv_id":"2509.06428","evidence_quote":"Provides the OO and Ne-Ne event-selection criteria and the anisotropic-flow evidence that frame the analysis."},{"cited_title":"Evidence for parton energy loss in oxygen$-$oxygen collisions at $\\mathbf{\\sqrt{s_{\\rm NN}}=5.36}$ TeV","cited_arxiv_id":"2606.19967","evidence_quote":"Provides independent evidence for parton energy loss in OO that motivates reading the yield deficit as a jet-medium effect."},{"cited_title":"Multiplicity-dependent jet modification from di-hadron correlations in pp collisions at $\\sqrt{s} = 13$ TeV","cited_arxiv_id":"2409.04501","evidence_quote":"Supplies the per-trigger normalized correlation function method used to construct the jet-like yields."},{"cited_title":"Jet-like di-hadron correlations in pO, OO, and Ne--Ne collisions","cited_arxiv_id":"2609.24237","evidence_quote":"Reports the near-side peak broadening and model comparisons in pO, OO, and Ne-Ne that this contribution extends."},{"cited_title":"No-quenching baseline for energy loss signals in oxygen-oxygen collisions","cited_arxiv_id":"2410.22405","evidence_quote":"Provides a no-quenching baseline calculation for OO showing that cold-nuclear-matter effects can shift the relative yield away from unity."},{"cited_title":"Selection bias effects on high-p T yield and correlation measurements in Oxygen+Oxygen collisions,","cited_arxiv_id":null,"evidence_quote":"Quantifies event-activity selection biases on high-transverse-momentum yields and correlations in OO, the alternative explanation left open by the paper."}],"review_version":1}