{"id":"8c9030fd-ac9a-4063-9f4a-a1880a56e076","arxiv_id":"2607.11652","paper_version":1,"verdict":"ACCEPT","confidence":"HIGH","novelty_score":5.5,"correctness_risk":"low","formal_verification":"none","parameter_count":3,"one_line_summary":"MiNLO yields NLO predictions for full off-shell pp\to ttW+(j/jj) that agree with fixed-order results while reducing scale dependence for multi-jet samples, and merging improves the inclusive ttW+ description.","lead":"The paper implements the MiNLO multi-scale NLO method in Helac-NLO and applies it to full off-shell ttW+ production with up to two jets in the multi-lepton channel at 13 TeV. It shows that dynamic scales plus Sudakov factors reduce scale uncertainties relative to fixed-order NLO for higher jet multiplicities and that simple merging improves the inclusive description.","discovery_kind":"new_application","skeptic_critique":{"model":"grok-4.5","headline":"No significant objection identified","rationale":"The reader correctly isolates the only genuine residual freedom (arbitrary q_core) and notes that the paper itself quantifies its impact. Because that freedom is already explored (Table 2, Fig. 2, Section 6) and does not overturn the agreement-within-uncertainties claim, no further load-bearing concern arises. The concrete test above simply reconfirms the size of the already-reported systematic; a null result leaves the ACCEPT verdict intact.","tokens_in":31189,"tokens_out":387,"duration_ms":3991,"concrete_test":"Recompute the merged integrated cross section of Eq. (6.2) at p_T,merging = 60 GeV with the alternative core-scale definition of Eq. (2.17) (var2) instead of the default geometric mean; if the central value or the 7-point uncertainty band shifts by more than the ~4 % difference already quoted relative to pure NLO, the residual q_core sensitivity would be larger than claimed.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The paper’s central numerical claim—that MiNLO and fixed-order NLO agree within uncertainties while MiNLO reduces scale dependence for higher jet multiplicity or suboptimal scales—is directly supported by Tables 1–4 and Figs. 2–5, 10–12. The residual freedom in q_core (Section 2) is already flagged by the reader and is treated as an explicit systematic in the paper (alternative prescriptions in Table 2, ordering condition Eq. (2.13), and the merging discussion in Section 6). No internal inconsistency or unsupported leap appears; the LO treatment of the two-jet sample is likewise openly stated as a limitation for future work. The argument therefore holds under the conditions the authors themselves set.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.5","summary":"The manuscript implements the multi-scale improved NLO (MiNLO) method inside Helac-NLO and applies it to full off-shell pp → e+νe μ-ν̄μ τ+ντ bb(j/jj) production in the multi-lepton channel at √s = 13 TeV. It compares standard fixed-order (N)LO QCD predictions with Mi(N)LO results at the integrated and differential levels for several fixed and dynamical core-scale choices, documents the residual freedom in q_core and the clustering radius R, and constructs multi-jet merged predictions (up to two extra jets) intended to improve the description of the inclusive ttW+ process. The central numerical claim is that MiNLO and fixed-order NLO agree within scale uncertainties for all considered central scales, while MiNLO systematically reduces those uncertainties once two extra jets are present or when suboptimal fixed scales are used.","tokens_in":31387,"tokens_out":1107,"duration_ms":9055,"significance":"Full off-shell NLO QCD for ttW+ with additional jets is a high-complexity calculation of direct relevance to LHC multi-lepton measurements and SMEFT analyses. Extending MiNLO to this final state, implementing it in Helac-NLO, and validating against Sherpa for simpler processes constitute a genuine technical advance. The exhaustive scale-variation tables, alternative R/μ R/resolution-scale variants, and differential distributions with uncertainty bands make the comparison reproducible and useful for the community. The residual freedom in q_core is treated as an explicit systematic rather than hidden, which strengthens the paper.","major_comments":[{"comment":"Section 6 and Eqs. (6.1)–(6.2): the multi-jet merging is performed with an explicit pT,merging cut rather than the MiNLO-style merging without a merging scale that is standard in the literature (Hamilton et al., 2013; Hamilton et al., 2016). The authors correctly note that a full MiNLO merging for this process would require dedicated resummation matching that is not yet available, but the present construction therefore remains a conventional exclusive/inclusive sum. The claim that the merged sample “improves the description” of the underlying process should be qualified more carefully: for well-chosen dynamical scales the reduction in scale uncertainty is modest and still depends on the arbitrary pT,merging value (Fig. 6).","section":null},{"comment":"Section 6 and Table 4 / Appendix A: the two-jet sample is retained only at LO. While this is openly stated as a limitation for future work, the merged predictions that include this sample (Eq. (6.2)) inherit large LO scale uncertainties that partially cancel the benefit of MiNLO on the lower-multiplicity samples. A quantitative estimate of how much the merged uncertainty bands would shrink once the NLO ttW+jj calculation becomes available would strengthen the central claim of Section 6.","section":null}],"minor_comments":[{"comment":"Section 2, Eq. (2.4): the rapidity/momentum-sign condition used to resolve the initial-state clustering ambiguity is sensible but not standard; a short sentence comparing it with the treatment in Sherpa or the original MiNLO papers would help the reader.","section":null},{"comment":"Table 1 and Table 2: the K-factor columns are useful, but the last column (σMiNLO/σNLO) is almost always 0.97–1.00; stating this explicitly in the text would make the agreement more immediately visible.","section":null},{"comment":"Figures 3–5 and 10–12: the bottom panels show scale-uncertainty bands normalized to the central value; adding a second ratio panel that directly overlays the absolute size of the MiNLO versus NLO uncertainty bands would make the claimed reduction easier to judge by eye.","section":null},{"comment":"References: the recent NNLO QCD results for on-shell ttW (Becchetti et al., 2606.09503) are cited; a brief remark on how the present full-off-shell MiNLO study complements those calculations would be welcome.","section":null},{"comment":"Typographical: “Mi(N)LOnoξ F” is used both as a label and as a subscript; a consistent notation (e.g. MiNLO|no ξ F) would improve readability.","section":null}],"recommendation":"minor_revision","confidential_remarks":"The paper is a solid, carefully executed technical contribution that fits well in JHEP. The two major points are presentational/qualification issues rather than correctness problems; once the authors clarify the nature of the merging and the LO limitation of the two-jet sample, the manuscript should be ready for acceptance. No concerns about novelty disclosure or citation patterns."},"author_rebuttal":null,"desk_editor":{"model":"grok-4.5","letter":"This is a careful, useful technical paper. The new pieces are the first MiNLO treatment of the fully off-shell multi-lepton ttW final state (with one and two extra jets) and a public implementation of the method inside Helac-NLO. Both are real and non-trivial; the rest is standard CKKW/MiNLO machinery applied to a process that actually needs better jet modeling.\n\nWhat they do well is the comparison itself. Tables 1–4 and the differential plots show that MiNLO and ordinary NLO agree inside scale bands for every sensible central scale they tried, while MiNLO systematically shrinks those bands once two extra jets are present or when the core scale is deliberately bad. They also checked alternative R values, the two µR prescriptions, and the no-ξF variant; the shifts are at the 1 % level. Cross-checks against Sherpa for simpler on-shell processes give confidence that the Helac-NLO coding is correct. The merging exercise (Section 6) is honest about residual sensitivity to pT,merging and to the LO treatment of the two-jet sample.\n\nThe soft spots are exactly the ones the authors flag. The core scale q_core remains an external choice; the algorithm only fixes the nodal scales of the extra jets. When q_core is already good the gain is modest, and the merged predictions still feel that freedom. Keeping the second jet at LO is a clear limitation for the multi-jet sample; they say so and leave it for future work. None of this undercuts the central numerical claim.\n\nThis is for people who need precision predictions for multi-lepton ttW as a background or as a SMEFT probe. It will not change how anyone thinks about resummation, but it is a clean, reproducible advance that experimental groups and other theory groups can use immediately. I would send it to referees without hesitation.","headline":"Solid first MiNLO application to fully off-shell multi-lepton ttW+(j/jj) plus a new Helac-NLO implementation; claims hold up under the authors' own tests.","tokens_in":31955,"tokens_out":498,"would_cite":true,"duration_ms":5245,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.5","headline":"Dynamic multi-scale NLO and jet merging improve full off-shell ttW+ predictions at the LHC.","keywords":["MiNLO","ttW+","full off-shell","NLO QCD","scale setting","jet merging","Sudakov form factors","multi-lepton"],"falsifier":"Compute the same full off-shell multi-lepton distributions with an independent NLO generator that implements a different multi-scale prescription (or with a complete NNLO calculation once available) and check whether the central values and residual scale bands still agree within a few percent for the same fiducial cuts.","tokens_in":32123,"feed_emoji":"⚛️","tokens_out":683,"duration_ms":6403,"temperature":0.7,"pith_summary":"This paper shows that assigning renormalization and factorization scales from the most probable jet branching history, together with Sudakov form factors that resum large logarithms, produces NLO QCD predictions for the full off-shell multi-lepton ttW+ process that agree with ordinary fixed-order results while systematically shrinking scale uncertainties once extra jets are present. The same multi-scale machinery is then used to merge 0-, 1- and 2-jet samples so that the inclusive multi-lepton signature is described more accurately, especially in regions where hard radiation is important. The comparison is performed at 13 TeV for both integrated fiducial rates and differential distributions, and the method is implemented inside a public multi-purpose NLO framework so that it can be reused for other processes. Readers who care about precision modeling of same-sign lepton backgrounds or about reducing theory error on a process that already shows mild tension with data will find the concrete numerical gains and the residual freedom in the core-scale choice directly relevant.","feed_headline":"Dynamic scales shrink theory error on full off-shell ttW+","feed_subtitle":"MiNLO and jet merging tighten predictions for multi-lepton LHC backgrounds","key_machinery":"The MiNLO algorithm: an inverse kT clustering that reconstructs ordered nodal scales qi for every additional jet, assigns \theta s(qi) and Sudakov form factors to those scales, and expands the form factors to cancel double-counted NLO terms, leaving only an arbitrary core-process scale qcore free.","core_discovery":"For the full off-shell pp\to e+\nu e \nu¯\tau+\nu\tau bb¯(j) processes at 13 TeV, multi-scale improved NLO (MiNLO) predictions agree with standard fixed-order NLO within scale uncertainties for every central-scale choice examined, yet the MiNLO scale bands are systematically smaller once two extra jets are present or when a suboptimal fixed scale is used; merging the 0-, 1- and 2-jet samples with a merging cut further reduces those bands for most differential observables relative to pure NLO.","pith_inferences":[],"forward_implications":[],"fun_headline_variants":["MiNLO shrinks scale bands on full off-shell ttW multi-leptons","Jet merging tightens uncertainties for off-shell ttW+ at 13 TeV","Dynamic scales cut theory error bands once two jets appear","Merged 0-1-2 jet MiNLO improves multi-lepton ttW backgrounds","MiNLO matches fixed NLO yet yields narrower bands for ttW+"],"cache_read_input_tokens":16512,"weakest_assumption_plain":"The overall energy scale of the core process without extra jets is still chosen by hand; only the scales of the additional jets are fixed by the clustering algorithm.","fun_headline_variants_meta":{"raw":{"variants":["MiNLO shrinks scale bands on full off-shell ttW multi-leptons","Jet merging tightens uncertainties for off-shell ttW+ at 13 TeV","Dynamic scales cut theory error bands once two jets appear","Merged 0-1-2 jet MiNLO improves multi-lepton ttW backgrounds","MiNLO matches fixed NLO yet yields narrower bands for ttW+"]},"model":"grok-4.5","effort":"low","cost_usd":0.007026,"raw_usage":{"total_tokens":1803,"prompt_tokens":948,"num_sources_used":0,"completion_tokens":88,"cost_in_usd_ticks":70260000,"prompt_tokens_details":{"text_tokens":948,"audio_tokens":0,"image_tokens":0,"cached_tokens":0},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":767,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":948,"tokens_out":88,"duration_ms":6157,"temperature":1.0,"reasoning_tokens":767,"cache_read_input_tokens":0,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-07-14T04:05:17.558243+00:00","model_set":{"reader":"grok-4.5"},"falsifier":"Compute the same full off-shell multi-lepton distributions with an independent NLO generator that implements a different multi-scale prescription (or with a complete NNLO calculation once available) and check whether the central values and residual scale bands still agree within a few percent for the same fiducial cuts.","supporting_citations":[],"review_version":1}