{"id":"e0bec6df-feea-48e1-8650-cf8c4ca8dbb6","arxiv_id":"2508.01905","paper_version":1,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":6.0,"correctness_risk":"unknown","formal_verification":"none","parameter_count":0,"one_line_summary":"A new data-driven analysis of CLAS electron-scattering data measures proton transparency on helium, carbon, and iron, confirming earlier results and showing that the GENIE neutrino-interaction generator mis-models proton rescattering at low momenta.","lead":"Using CLAS electron-scattering data from Jefferson Laboratory, the e4nu collaboration measured proton transparency on helium, carbon, and iron, that is, the fraction of knocked-out protons that escape the nucleus without rescattering. The result matters for neutrino oscillation experiments, whose simulations of neutrino-nucleus interactions must model exactly these rescattering effects.","discovery_kind":"new_method","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The load-bearing risk is the purity of the quasi-elastic denominator used to define the transparency ratio: if the 'should-have-been-knocked-out' sample is built with generator-dependent background subtraction, the ratios inherit model dependence; the supplied text is too corrupted to check this…","rationale":"The paper's strongest claim is a new data-driven proton-transparency ratio on He, C, and Fe from CLAS data, plus a finding that GENIE mismodels low-momentum transparency. The load-bearing premise is exactly that the QE denominator can be defined without significant model input. I agree with the reader that this is structurally prior to the measurement: if the denominator is contaminated by backgrounds or defined using a generator, the ratio is not model-independent. I do not find an independent flaw in the abstract's logic; GENIE is used as a benchmark, not an input, so there is no visible circularity. The full text supplied here is heavily corrupted and even carries a header line for arXiv:2508.01906, a different paper; per the review rule I flag this as an obstacle rather than as evidence of misconduct. The proposed test would settle the concern by isolating denominator sensitivity. Because the reader already assigned UNVERDICTED at low confidence due to unreadable methods, this stress-test does not change the verdict; it sharpens what a clean full text must demonstrate.","tokens_in":22592,"tokens_out":4073,"duration_ms":50907,"concrete_test":"After obtaining a clean copy, locate the denominator definition and background-subtraction section (expected near Sections 3-4) and run a closure-style reanalysis of the electron-scattering candidates: (1) subtract non-QE backgrounds with two independent models, e.g., GENIE and a data-driven sideband fit with no generator shape; (2) vary the QE missing-energy/missing-momentum window by +/-20 MeV; (3) compare the resulting transparency ratios and their quoted point-to-point systematics. If the ratios shift by more than the reported uncertainties, the denominator is not data-driven and the central claim is unsupported; if they are stable, the concern is resolved.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central observable is a ratio N_detected(p)/N_QE, where N_QE is a constructed class of electron-scattering events in which a proton is asserted to have been knocked out. N_QE is not directly observed; it must be selected by cuts and corrected for backgrounds. The abstract gives no details, and the supplied full text is unreadable and interleaved with a header for a different arXiv number, so the selection, background subtraction, and acceptance corrections cannot be inspected. The specific unresolved risk is that non-QE processes (single-pion production, 2p-2h knockout, radiative tails, and neutron-knockout events that mimic proton QE kinematics) migrate into the QE denominator. If those backgrounds are subtracted using GENIE or any generator shape, the 'data-driven' claim is weakened: the denominator, not just the comparison, carries generator dependence. Because transparency is a ratio, a few-percent background error in the denominator translates directly into the ratio, which is exactly the scale needed to create or erase the reported low-momentum GENIE discrepancy. Consistency with earlier theory-based transparency measurements is a useful check, but those earlier measurements use the same bound-proton assumptions and are not an independent test of denominator purity.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The paper claims a new measurement of proton transparency in electron-nucleus scattering using CLAS data on helium, carbon, and iron, based on a 'data-driven' ratio of detected-proton events to quasi-elastic events in which a proton should have been knocked out. The abstract reports consistency with previous theory-based transparency measurements and states that GENIE needs improved nuclear ground-state and rescattering descriptions, especially at lower proton momenta. The supplied full text is almost entirely unreadable due to character encoding corruption, and it contains an arXiv header for a different paper (2508.01906v1 [cs.HC]), so the technical content cannot be inspected.","tokens_in":22719,"tokens_out":4997,"duration_ms":56890,"significance":"If the measurement is correct, it would provide a data-driven alternative to the conventional theory-ratio extraction of proton transparency and a direct test of GENIE's final-state interaction models, which is relevant to neutrino oscillation systematic uncertainties. However, the significance can only be assessed once the method and uncertainties are available; as submitted, the paper offers no legible evidence for the central claims.","major_comments":[{"comment":"The supplied manuscript text is corrupted mojibake throughout, with a header reading 'arXiv:2508.01906v1 [cs.HC] 3 Aug 2025' that belongs to a different submission. No equation, table, figure, or analysis section can be read. This makes it impossible to verify the extraction method, the selection criteria, the detector corrections, or the comparisons claimed in the abstract; a readable resubmission is required before technical review.","section":"Full Text"},{"comment":"The transparency ratio is defined as the number of events with a detected proton divided by the number of QE events 'where a proton should have been knocked out.' The abstract does not state how the denominator is constructed, which cuts define the QE sample, or how backgrounds (single-pion production, two-nucleon knockout, radiative tails, neutron-knockout events that mimic proton QE kinematics) are rejected. If the denominator is obtained with generator-dependent corrections, the ratio is not purely data-driven and inherits model uncertainty. Because transparency is a ratio, small denominator errors map linearly into the result and could create or remove the reported low-momentum GENIE discrepancy.","section":"Abstract"},{"comment":"No uncertainty breakdown is reported. The claim that the results are 'consistent with previous measurements' and the conclusion that GENIE fails to reproduce the ratios 'especially at lower proton momenta' carry no statistical or systematic errors, no pulls or chi-squared values, and no quantitative comparison. Without these, the consistency and discrepancy claims are not testable.","section":"Abstract"},{"comment":"The term 'data-driven' needs a precise definition relative to the earlier CLAS transparency measurements. If the earlier measurements used a theoretical cross-section in the denominator and the new method uses data-derived kinematics to define the QE set, the authors should state explicitly where GENIE or other models do and do not enter; otherwise the novelty and the claimed independence from model input cannot be evaluated.","section":"Abstract"}],"minor_comments":[{"comment":"The manuscript's arXiv identifier in the header should be checked; it currently shows 2508.01906v1 [cs.HC], which appears to be a different paper.","section":"Header"},{"comment":"The definition of 'without significant rescattering' should be operationalized, for example with a missing-energy window and a proton momentum threshold, so the measured ratio can be interpreted as a transparency.","section":"Abstract"},{"comment":"The paper should state the data-taking period, integrated luminosity, and target thicknesses for He, C, and Fe; none of these are visible in the submitted text.","section":"Full Text"},{"comment":"A reference list could not be inspected due to the corruption; the authors should ensure all prior CLAS transparency and GENIE validation works are cited in the resubmission.","section":"References"}],"recommendation":"major_revision","confidential_remarks":"The current upload is not reviewable; I recommend requesting a clean resubmission before assigning a new referee round. The interleaved header for arXiv:2508.01906 suggests a submission error rather than a physics flaw. The core question of denominator purity should be addressed explicitly in the revised manuscript."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Quick take: the abstract describes a genuinely new way to measure proton transparency — a ratio of detected-proton events to a quasi-elastic denominator — on helium, carbon, and iron from CLAS, plus a pointed result that GENIE mismodels low-momentum transparency. If the analysis holds, it is useful for neutrino oscillation systematics. But the full text I received is unreadable mojibake, interleaved with a header for a different arXiv number, so none of the methods could be checked. I am judging the abstract only.\n\nWhat is new: earlier extractions used a ratio to theory; this uses a data-driven ratio. That is a real difference. The consistency check against previous measurements is good practice. The GENIE comparison is the practically important part — oscillation experiments lean on GENIE, and a specific low-momentum failure mode is actionable.\n\nSoft spots: the load-bearing point is the denominator. \"Events where a proton should have been knocked out\" is not directly observed. It has to be selected and corrected for pion production, 2p-2h knockout, radiative tails, and acceptance. If those corrections use generator shapes, the method inherits model dependence, and \"data-driven\" overstates it. The stress-test note is right about this. Also, consistency with earlier theory-ratio measurements is weaker than it looks, because those measurements share the same bound-proton assumptions. That is not fatal, but it is a real limitation. On what is visible, there is no fitted-parameter circularity: GENIE is a benchmark, not an input to the ratio.\n\nThe corrupted manuscript is the biggest practical problem. It cannot go to referees in this form. The authors need to fix the submission. If the text is restored and the denominator selection is shown to be robust under generator variations, this is a solid paper worth citing. For now, it is an interesting abstract with an unverifiable middle.\n\nMy recommendation: do not desk-reject the underlying work — send it to review once a readable version is uploaded. The physics is important enough to merit referee time. But the current artifact is not reviewable.","headline":"A plausible and useful new transparency measurement, but the corrupted manuscript makes it unverifiable; deserves review after cleanup.","tokens_in":24122,"tokens_out":1983,"would_cite":false,"duration_ms":23409,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":["25.30.Fj","24.10.Ht","13.15.+g"],"model":"deepseek-v4-flash","headline":"A data-driven measurement of proton transparency shows GENIE mismodels nuclear rescattering.","keywords":["proton transparency","final-state interactions","GENIE event generator","neutrino-nucleus interactions","CLAS","quasi-elastic electron scattering","nuclear ground state","Jefferson Lab"],"falsifier":"Re-run the analysis with alternative quasi-elastic event selections, for example different missing-energy or momentum-transfer windows, and check whether the extracted transparency ratios shift by more than the quoted systematic uncertainties; any such shift would show the denominator is not model-independent.","tokens_in":22316,"feed_emoji":"⚛️","tokens_out":5151,"duration_ms":60352,"temperature":0.7,"pith_summary":"This paper tries to establish that proton transparency—the probability that a proton knocked out of a nucleus leaves without rescattering—can be measured from electron-scattering data without leaning on a theoretical model for the expected signal. The authors use CLAS data on helium, carbon, and iron and define transparency as the ratio of events with a detected proton to quasi-elastic events in which a proton should have been produced, building both sides from data. Their measured ratios agree with older results that used theory for the denominator, and they show that the GENIE event generator does not reproduce the ratios, especially at low proton momentum. This matters because GENIE is the standard simulation tool for neutrino-oscillation experiments; if it misdescribes the nuclear ground state or proton rescattering, neutrino-interaction rates and their uncertainties shift.","feed_headline":"Proton escape data show GENIE falls short at low momentum","feed_subtitle":"New electron-scattering ratios on helium, carbon, iron pin down where neutrino simulators go wrong.","key_machinery":"The central object is the transparency ratio $T=N_{\\mathrm{det}}/N_{\\mathrm{QE}}$, with $N_{\\mathrm{det}}$ the number of electron-scattering events containing a detected proton and $N_{\\mathrm{QE}}$ the number of events in which a proton should have been knocked out in a quasi-elastic collision. Previous measurements formed $N_{\\mathrm{QE}}$ from reaction theory; this paper instead constructs it from data, which is the new machinery that makes the test of GENIE more direct. The ratios are measured on helium, carbon, and iron as a function of proton momentum, so the target and momentum dependence carries the sensitivity to the nuclear ground state and to rescattering.","core_discovery":"The paper's central claim is that the new data-driven extraction gives unbiased estimates of proton escape probabilities, and that GENIE fails to reproduce them. Formally, the transparency is the ratio of detected-proton events to a quasi-elastic 'should-have-seen-a-proton' sample. The measured values are consistent with previous transparency measurements that divided by theoretical predictions, which supports both the old results and the new method. The comparison with GENIE shows the generator must improve its description of both the nuclear ground state and final-state rescattering, with the largest failures appearing at lower proton momenta.","pith_inferences":["Because modern neutrino detectors rely on reconstructing low-momentum protons, the largest GENIE discrepancies could translate into sizeable systematic errors in oscillation analyses; this is my inference, not the paper's stated conclusion.","The same ratio method could be extended to argon or other nuclei to map the $A$-dependence of transparency and directly inform detector simulations for next-generation experiments.","A natural next step is to use the measured ratios as a tuning dataset for GENIE's cascade models, turning the discrepancy into a quantitative constraint.","The 'data-driven' denominator still relies on a definition of quasi-elastic kinematics, and its cleanliness can be tested by varying the event-selection cuts, something the paper does not fully explore."],"forward_implications":["Neutrino-oscillation experiments that use GENIE will need to revise their treatment of nuclear ground states and proton rescattering, particularly for low-momentum protons.","The measured transparency ratios provide a direct, model-robust benchmark for tuning final-state interaction models in event generators.","The data-driven denominator method can be applied to other targets and kinematics without waiting for improved theory predictions.","Agreement with previous theory-based transparency measurements validates the older results while removing some of their model dependence."],"supporting_citations":[],"fun_headline_variants":["New transparency ratios expose GENIE's low-momentum proton rescattering errors","Data-driven proton escape ratios on He, C, Fe show GENIE needs work at low p","CLAS transparency data on He, C, Fe indicate GENIE's low-momentum flaws","New proton escape extraction exposes GENIE's low-momentum nuclear model gaps","Proton transparency ratios from CLAS challenge GENIE's low-momentum predictions"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The measurement stands on the assumption that the sample of events where a proton should have been knocked out can be selected from data without significant contamination by other reactions or detector losses; if that sample is not clean, the transparency ratio is not purely data-driven.","fun_headline_variants_meta":{"raw":{"variants":["New transparency ratios expose GENIE's low-momentum proton rescattering errors","Data-driven proton escape ratios on He, C, Fe show GENIE needs work at low p","CLAS transparency data on He, C, Fe indicate GENIE's low-momentum flaws","New proton escape extraction exposes GENIE's low-momentum nuclear model gaps","Proton transparency ratios from CLAS challenge GENIE's low-momentum predictions"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.001184,"raw_usage":{"total_tokens":4846,"prompt_tokens":856,"completion_tokens":3990,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":472,"completion_tokens_details":{"reasoning_tokens":3880}},"tokens_in":472,"tokens_out":3990,"duration_ms":36383,"temperature":1.0,"reasoning_tokens":3880,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-06T05:18:07.392955+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"Re-run the analysis with alternative quasi-elastic event selections, for example different missing-energy or momentum-transfer windows, and check whether the extracted transparency ratios shift by more than the quoted systematic uncertainties; any such shift would show the denominator is not model-independent.","supporting_citations":[],"review_version":1}