{"id":"f6aca837-bbf9-41c3-9a9c-9ed96a6d53ec","arxiv_id":"1308.4379","paper_version":2,"verdict":"ACCEPT","confidence":"MODERATE","novelty_score":5.0,"correctness_risk":"low","formal_verification":"none","parameter_count":5,"one_line_summary":"Form factor ratios extracted from B to K-star dilepton angular data at low recoil, combined with heavy-quark symmetry and LCSR input, yield Standard-Model-consistent predictions for A_FB and P'_5.","lead":"The authors extract B to K-star form factor ratios at low hadronic recoil from LHC-era angular data, then use them to predict the forward-backward asymmetry and P'_5. The predictions agree with Standard Model expectations, providing a consistency check on the short-distance structure of rare B decays.","discovery_kind":"unclear","skeptic_critique":{"model":"selfhosted/deepseek-v4.1-flash","headline":"In the low-recoil OPE limit A_T^(2) = 1 − P'_4², so F_L, A_T^(2), P'_4 supply at most two independent hadronic constraints; the A_FB and P'_5 'predictions' therefore test OPE universality plus the SM ρ2/ρ1, not the form factors independently.","rationale":"The paper is careful and largely transparent: it states that only form factor ratios enter A_FB and P'_5 (Eqs. 46–47), that the SE2 fit without theory input is unconstrained, and that LEL/LCSR input is needed for large-recoil predictivity. The reader's pick of the low-recoil OPE factorization as the weakest assumption is defensible, but that factorization is a cited, published result (Refs. [26,27,29,34]) and the paper acknowledges its corrections, so it is not the place where an internal concern lands. The sharper issue is the algebraic redundancy among the observables: A_T^(2) = 1 − P'_4² in the OPE limit, so the fit has fewer independent hadronic constraints than the number of observables suggests, and the A_FB/P'_5 comparison is a test of OPE universality and the SM ρ2/ρ1 rather than an independent form factor determination. This does not make the central claim false — the agreement is real and the OPE relations are worth testing — but it means the abstract's 'good agreement with the SM' should be read as a consistency check, not a precision confirmation. The paper's other caveats (right-handed currents contaminating f⊥/f‖ at up to 30%, c-cbar resonances in A_FB and P'_5, the ~2σ P'_4 tension, the SE1 LCSR fit failure) are all acknowledged and do not add a new load-bearing concern. I would keep the verdict at ACCEPT; a clarifying sentence on the A_T^(2) + P'_4² = 1 relation and on the reduced independence of the A_FB/P'_5 check would strengthen the paper without changing its conclusions.","tokens_in":52726,"tokens_out":47381,"duration_ms":644052,"concrete_test":"Take the LHCb binned values of A_T^(2) and P'_4 in Table II, apply the factor −2 correction to P'_4 noted in the table footnote, and check whether A_T^(2) + P'_4² = 1 holds within the quoted uncertainties. Then re-run the SE2 fit using only F_L and P'_4 (dropping A_T^(2)) and compare the extracted ratios and the A_FB, P'_5 predictions with Tables III–V. If the ratios and predictions are unchanged within uncertainties, the redundancy is harmless and the paper's claim stands; if they shift materially, the fit's effective information content is smaller than the five-observable presentation implies.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim (abstract:s3) compares SM predictions for A_FB and P'_5 — built from form factor ratios extracted from F_L, A_T^(2), P'_4 — against measured A_FB and P'_5. The reader calls this an out-of-sample check on the form factor ratios. It is weaker than that. From Eq. (8), A_T^(2) = (f⊥²−f‖²)/(f⊥²+f‖²) and P'_4 = √2 f‖/√(f‖²+f⊥²), so A_T^(2) = 1 − P'_4² identically in the OPE limit. The three fit inputs therefore carry at most two independent hadronic constraints (F_L and one of A_T^(2)/P'_4), which is exactly the number needed to fix the two ratios f0/f‖ and f⊥/f‖. A_FB and P'_5 (Eqs. 46–47) are then algebraic functions of those same ratios and the short-distance ratio ρ2/ρ1, which is fixed to its SM value with ~2% uncertainty. So the comparison is a consistency check of the OPE relations among the five angular observables plus the SM value of ρ2/ρ1; it is not an independent determination of the form factors. This is consistent with the paper's own finding that the unconstrained SE2 fit leaves p⊥, p‖, p0 essentially undetermined (Table III) and that LEL or LCSR input is required to be predictive. The paper does not state the A_T^(2) + P'_4² = 1 relation, and the abstract's 'good agreement with the SM' reads as a stronger, more independent statement than the data support. The claim is not wrong, but its information content is smaller than the five-observable comparison suggests.","agreement_with_reader":"partial"},"referee_report":{"model":"selfhosted/deepseek-v4.1-flash","summary":"The manuscript extracts B→K* transition form factor ratios at low hadronic recoil from the published high-q² angular data on F_L, A_T^(2) and P'_4 (BaBar, CDF, LHCb, ATLAS, CMS), using a z-series parametrization of the transversity form factors at first (SE1) and second (SE2) order. Heavy-quark-symmetry relations (improved Isgur-Wise and large-energy limits) and updated LCSR ratios at q²=0 are added as fit constraints, and the LCSR ratios themselves are recomputed with correlated errors and updated hadronic inputs, giving R(0)=V(0)/A1(0)=1.31±0.10 and R'(0)=A2(0)/A1(0)=0.83±0.08 (Eq. 33). The fitted ratios are then used to predict the forward-backward asymmetry A_FB and the angular observable P'_5 at low recoil (Eqs. 46–47), and the predictions are compared with the experimental world averages in Tables IV and V. The authors conclude that the low-recoil A_FB and P'_5 data agree with the Standard Model, and that order-one new physics confined to C9 is strongly disfavoured. The paper is a follow-up to Ref. [30] with more data, added symmetry input, and a correlated-error LCSR update.","tokens_in":26830,"tokens_out":9087,"duration_ms":97685,"significance":"The result is a useful and timely benchmark: data-extracted form factor ratios at low recoil provide an independent cross-check of lattice and LCSR determinations in a region where both are used for new-physics searches, and the correlated-error update of the LCSR ratios in Eq. (33) is a concrete deliverable that the community can use directly. The comparison of the fitted ratios with the A_FB and P'_5 world averages is a genuine, if limited, test of the low-recoil OPE short-distance structure, since those two observables depend on the short-distance ratio ρ2/ρ1 while F_L, A_T^(2) and P'_4 do not. The paper is candid about its tensions (the non-convergence of the SE1 LCSR fit, the ~2σ P'_4 discrepancy, the need for large-recoil input in SE2), and the fitting code (Lucy with NLopt) is named, which aids reproducibility. The main caveat is that the information content of the five-observable comparison is smaller than the abstract's phrasing suggests, as detailed below.","major_comments":[{"comment":"In the low-recoil OPE limit the three fit inputs are not independent: Eq. (8) gives A_T^(2) = (f⊥²−f‖²)/(f⊥²+f‖²) and P'_4 = √2 f‖/√(f‖²+f⊥²), so identically A_T^(2) = 1 − P'_4². The three observables therefore supply at most two independent hadronic constraints, exactly the number needed to fix f0/f‖ and f⊥/f‖. This identity is nowhere stated in the manuscript, and it changes how the central claim should be read. A_FB and P'_5 (Eqs. 46–47) are algebraic functions of the same two ratios times ρ2/ρ1, so the comparison with data tests the OPE universality of Eq. (1) and the Standard-Model value of ρ2/ρ1 rather than determining the form factors independently. That is still a meaningful test and is in fact what the conclusion of §VI says, but the abstract's 'good agreement with the Standard Model' reads as a stronger, more independent statement than the data support. The authors should state the identity explicitly, rephrase abstract:s3 accordingly, and note that the χ² drop of O(5–10) when P'_4 is removed from the fit (§IV C) is expected once one recognises that P'_4 and A_T^(2) carry the same hadronic information.","section":"§II, Eq. (8); abstract:s3","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The plain SE2 fit returns α⊥/α‖ = 7.02 (+3.50/−4.27), p‖ = −1.99 (+3.79/−6.92), p⊥ = 3.84 (+0.00/−6.09), p0 = 3.14 (+0.37/−2.29), V(0)/A1(0) = 5.90 (+2.99/−3.64) and A2(0)/A1(0) = 0.00 (+0.57/−0.00). Several of these asymmetric errors terminate at zero, indicating parameters pinned at their bounds, and V(0)/A1(0) = 5.9 is wildly at odds with both the LCSR value 1.31±0.10 (Eq. 33) and the lattice results of Ref. [15]. Presenting this fit in §IV C as one of the three 'best suited presently for low recoil phenomenology', on the same footing as SE2 LEL and SE2 LCSR, is not justified by these numbers. Either the plain SE2 fit should be dropped from the recommended set, or the authors should explain why a fit with V/A1 ≈ 5.9 and parameters at their bounds is physically meaningful.","section":"§IV C, Table III (plain SE2 row)","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The manuscript states that the SE1 fit with LCSR input 'does not converge, i.e., returns a huge χ2 because the R-fit scheme used cannot resolve the > 1σ tension between A2(0)/A1(0) in SE1 and the corresponding LCSR value'. The quoted tension is small: SE1 fixes A2(0)/A1(0) = 0.93 (Eq. 43 with Eq. 42) against the LCSR value 0.83±0.08, i.e. about 1.25σ. A 1.25σ tension should not produce a divergent fit under any standard χ² or R-fit treatment, so either the effective tension is larger than stated or the R-fit implementation is behaving in a way the reader cannot assess. The authors should clarify the actual χ² value obtained, the number of degrees of freedom, and whether the failure is a property of the parametrization or of the fitting machinery.","section":"§IV C, bullet on the SE1 LCSR fit","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The conclusion that explanations of the large-recoil P'_5 anomaly based on order-one new physics in C9 alone are 'strongly disfavored' is stronger than the ~1σ-level low-recoil agreement reported in Tables IV and V supports. Given the identity A_T^(2) = 1 − P'_4² noted above, the sensitivity of the low-recoil P'_5 prediction to a shift δC9 should be shown explicitly, and the allowed range of δC9 following from the low-recoil data should be quoted as a number. Without that, the 'strongly disfavored' language should be softened to a statement about the present level of agreement.","section":"§VI, final paragraph; abstract:s3","authors_acknowledge":null,"authors_acknowledge_p":null}],"minor_comments":[{"comment":"The printed expression α0/α‖ = √(−z(t−,0))/2 = 0.29 is numerically inconsistent: with t− = (mB−mK*)² and t0 = 0 one finds z(t−,0) ≈ −0.174, so √(−z(t−,0))/2 ≈ 0.21, whereas the quoted 0.29 corresponds to √(−z(t−,0))/√2. The formula should read √(−z(t−,0))/√2, which is also what follows from f0(q²max)/f‖(q²max) = 1/√2.","section":"Eq. (42)","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The column header 'aP'_4' and the footnote explaining the factor −2 relative to the LHCb definition are easy to miss; a clearer column label and an explicit statement of which published number was rescaled would help the reader reproduce the fit inputs.","section":"Table II","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The fit treats the experimental data as uncorrelated Gaussian errors, although the entries in Table II come from the same experiments in adjacent q² bins and share systematic uncertainties. The impact of this simplification on the quoted χ²/dof and on the extracted ratios should be stated, even if only as a limitation.","section":"§IV B","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The 75% overall error correlation assumed for the lattice points of Ref. [15] is an ad hoc choice; a short statement of the sensitivity of the SE2 full fit to this correlation would strengthen the 'preview of future precision' claim.","section":"§IV B","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The treatment of the continuum-threshold uncertainty (varying sV0 and sA10 separately and adding linearly, versus correlated variation which drops the uncertainty below 2%) is well explained, but the reader would benefit from a sentence stating which of the two procedures is used for the central values quoted in Eq. (33).","section":"§III C","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"The caption states that the curves correspond to t0 = t−, topt and t0 = 0 'from top to bottom'; the ordering should be checked against the plotted curves, since at q² = 0 the three choices are close and the identification is not obvious by eye.","section":"Fig. 2 caption","authors_acknowledge":null,"authors_acknowledge_p":null},{"comment":"A number of typographical errors should be corrected: 'occassionally' (§II A), 'consquence' (§III B 1), 'pertubative' (§III B 1), 'satisifed' (§III C), 'Noticable' (§III C), 'discrepany' (§IV C), 'bayesian' (§I), and the stray 'rˆ ole' in §III B 1.","section":"Throughout","authors_acknowledge":null,"authors_acknowledge_p":null}],"recommendation":"major_revision","confidential_remarks":"The paper is a solid follow-up to Ref. [30] and the correlated-error LCSR update in Eq. (33) is the most concrete new deliverable. My main reservation is presentational rather than technical: the abstract's central claim (abstract:s3) overstates the independence of the A_FB/P'_5 comparison, because A_T^(2) and P'_4 are algebraically dependent in the OPE limit. The physics conclusion survives once the identity is stated, but the framing needs revision before the abstract can stand as written."},"author_rebuttal":null,"desk_editor":{"model":"selfhosted/deepseek-v4.1-flash","letter":"The genuinely new things here are (i) the updated LCSR ratios at q²=0, R(0)=1.31±0.10 and R'(0)=0.83±0.08, with an honest uncertainty treatment — the argument that correlated continuum thresholds drop the s0 error below 2% is the right way to think about it, and they say so; (ii) the e.o.m./Isgur-Wise analysis in Sec. III, especially the D_+(0) suppression argument and the tree-level LCSR demonstration in Appendix C, which is real work; and (iii) the SE2 fits with LEL/LCSR/lattice constraints, a clear improvement over [30]. The paper is also candid about what fails: the SE1+LCSR fit does not converge, and the P'_4 ~2σ tension is stated plainly as something the OPE cannot explain. That kind of reporting is worth crediting. The stress-test is right on the algebra. In the OPE limit A_T^(2) = 1 − P'_4² identically, so F_L, A_T^(2), P'_4 supply two independent hadronic constraints — exactly enough to fix f0/f‖ and f⊥/f‖. A_FB and P'_5 are then algebraic functions of those same ratios times ρ2/ρ1. So Tables IV and V test OPE universality plus the SM value of ρ2/ρ1, not the form factors independently. The paper never states the identity, and abstract:s3 reads stronger than the information content. That said, the body is more careful than the abstract: they note the unconstrained SE2 leaves the p's undetermined and that large-recoil input is needed to be predictive. This is a framing issue, not a wrong result. The comparison still carries weight — the OPE relations among five observables are non-trivial and could fail, and the A_FB/P'_5 data were not in the fit. Other soft spots, in proportion: the LCSR computation is summarized rather than reproduced, so Eq. (33) cannot be checked without going back to [10]; no public code (Lucy is named but not released). The claim that C9-only NP is 'strongly disfavored' is a touch strong given the identity issue, though it is consistent with [69,70] and the low-recoil argument is sound. Who it is for: people doing B→K*ℓℓ angular analyses, lattice and LCSR form factor practitioners, and anyone tracking the P'_5 anomaly story. Worth a serious referee.","headline":"A careful, useful update to the data-extracted B→K* form factor program — but the abstract's A_FB/P'_5 'agreement' is a consistency check of the OPE, not an independent form factor test.","tokens_in":27471,"tokens_out":2614,"would_cite":true,"duration_ms":28447,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"pith_extraction":{"msc":[],"pacs":["13.20.He","12.39.Hg","11.55.Hx"],"model":"selfhosted/deepseek-v4.1-flash","headline":"The hadronic form factors that blur predictions for the rare decay $B^0_s$ into a $K^*$ and a lepton pair can themselves be measured from that decay's angular data, and the resulting Standard Model predictions for two benchmark observables,","keywords":["B to K-star form factors","low-recoil operator product expansion","angular observables in rare B decays","P'_5 anomaly","light-cone sum rules","lattice QCD form factors","heavy quark symmetry","semileptonic B decays"],"falsifier":"A lattice or sum-rule determination of $V/A_1$ or $A_2/A_1$ at low recoil landing outside the fit bands shown in the paper's comparison figure, or a measured right-handed-current contribution that spoils the polarization-independent factorization, would undercut the extraction; the dedicated universality observables $H_T^{(1)}$ and $H_T^{(2)}/H_T^{(3)}$ proposed in the cited literature would test the factorization directly.","tokens_in":27711,"feed_emoji":"⚛️","tokens_out":3909,"duration_ms":37158,"temperature":0.7,"pith_summary":"The paper asks whether the hadronic form factors that smear predictions for the rare decay $B^0_s$ into a $K^*$ and a lepton pair can be measured from the same decay data, instead of being imported from lattice QCD or light-cone sum rules. The lever is that at low hadronic recoil the decay amplitudes factorize into a polarization-independent short-distance coefficient times a polarization-dependent form factor, so three angular observables — $F_L$, $A_T^{(2)}$ and $P'_4$ — depend on form factor ratios alone. Fitting those ratios to the published BaBar, CDF, LHCb, ATLAS and CMS measurements, with heavy-quark symmetry relations and updated sum-rule ratios added as constraints, yields $V(0)/A_1(0)=1.31$ and $A_2(0)/A_1(0)=0.83$ at roughly the ten-percent level. Feeding the ratios back into the forward-backward asymmetry $A_{FB}$ and the angular observable $P'_5$ — neither of which entered the fit — reproduces the measured values, so the Standard Model survives an out-of-sample check at low recoil.","feed_headline":"B-meson form factors read straight from decay data","feed_subtitle":"Angular data pin down hadronic uncertainties, and the Standard Model survives the low-recoil check.","key_machinery":"The load-bearing mechanism is the low-recoil operator product expansion, which at leading order in $1/m_b$ writes each transversity amplitude as $A_i^{L,R}(q^2) = C^{L,R}(q^2) f_i(q^2)$ up to corrections of order $m_b^{-1}$, with $C^{L,R}$ independent of the $K^*$ polarization. Because the short-distance coefficients cancel in ratios, the angular observables reduce to functions of the form factor ratios alone: $F_L = f_0^2/(f_0^2+f_1^2+f_0^2)$, and similarly for $A_T^{(2)}$ and $P'_4$. The second piece is the double ratio $R=(V/A_1)/(T_1/T_2)$, shown to equal $1+O(1/m_b)$ both at maximum recoil (from large-energy symmetry relations) and at low recoil (from the Isgur-Wise relations), which stitches the two kinematic ends together. The form factors themselves are parametrized by a $z$-series expansion truncated at first or second order, with the endpoint relations $F_L=1/3$, $A_T^{(2)}=-1$, $P'_4=1/2$ imposed exactly.","core_discovery":"The central claim is that form factor ratios in $B^0_s$ to $K^*$ transitions can be extracted from $B^0_s$ to $K^*$ dilepton data with enough control to be useful, and that the extracted ratios agree with lattice and light-cone sum rule determinations. The authors improve their earlier extraction by adding heavy-quark symmetry constraints, by studying how the low-recoil fit talks to the large-recoil region, and by recomputing the sum-rule ratios with correlated uncertainties, obtaining $R(0)=V(0)/A_1(0)=1.31$ and $R'(0)=A_2(0)/A_1(0)=0.83$. They argue that the double ratio $R=(V/A_1)/(T_1/T_2)$ equals one up to corrections of order $1/m_b$ at both maximum and low recoil, which is what licenses the extrapolation across the whole dilepton mass range. The payoff is that predictions for $A_{FB}$ and $P'_5$ built from the fitted ratios match the world averages, which the authors read as evidence that any new physics in the semileptonic short-distance coefficients must be small — in particular, explanations of the large-recoil $P'_5$ anomaly through an order-one shift in the Wilson coefficient $C_9$ alone are strongly disfavored.","pith_inferences":["If the double ratio $R$ really equals one at both kinematic ends, it becomes a clean null test: a measured deviation at intermediate dilepton mass would signal either a breakdown of quark-hadron duality or a right-handed current, independently of the form factor normalization.","The agreement on $A_{FB}$ and $P'_5$ is presently a check on the operator product expansion more than on new physics; once lattice input shrinks the error on $V/A_1$, the same comparison turns into a genuine search for shifts in the short-distance coefficients.","The same helicity factorization should hold for other $b \\to s$ transitions such as $B_s \\to \\phi \\ell^+\\ell^-$ and $B \\to K \\ell^+\\ell^-$, so the method offers cross-checks in hadronic environments with different systematic uncertainties.","Because the extraction is binned, the residual short-distance dependence that survives binning is a small but real systematic; finer bins would trade statistical power for a cleaner factorization test."],"forward_implications":["The data-extracted ratios give benchmarks that lattice QCD and light-cone sum rules must reproduce; the updated sum-rule values sit about 7% below earlier predictions, mainly because of revised hadronic inputs and correlated continuum thresholds.","Standard Model predictions for $A_{FB}$ and $P'_5$ at low recoil tighten relative to earlier estimates, with the quoted uncertainties coming from form factors alone and the short-distance coefficient uncertainty subleading at about 2%.","Explanations of the large-recoil $P'_5$ anomaly that rely on an order-one new-physics contribution to $C_9$ alone are strongly disfavored, since the low-recoil data are consistent with the Standard Model.","A roughly $2\\sigma$ discrepancy in $P'_4$ in the lower dilepton-mass bin cannot be accommodated within the operator product expansion and is flagged for further experimental investigation.","The fit scenarios combining data with large-energy or sum-rule input (SE2 LEL and SE2 LCSR) are put forward as the best currently available for low-recoil phenomenology, while a combined fit with lattice input previews the precision reachable with future data."],"supporting_citations":[{"why":"Supplies the low-recoil operator product expansion and the $1/m_b$ corrections that make the amplitude factorization the basis of the whole extraction.","marker":"[26]"},{"why":"Provides the assessment of higher-order and duality-violating corrections that the authors lean on to argue the universality holds at the few-percent level.","marker":"[27]"},{"why":"Defines the short-distance-independent observables and the coefficients $C^{L,R}$ whose cancellation lets form factor ratios be read off the angular data.","marker":"[25]"},{"why":"Supplies the Standard Model values of the short-distance factors $C^{L,R}$ and the framework for the universality observables used to bound right-handed currents.","marker":"[29]"},{"why":"The light-cone sum rule form factors whose ratios the paper updates, and whose correlated uncertainties it recomputes.","marker":"[10]"},{"why":"The lattice results on $V$, $A_1$ and $A_2$ that the extracted ratios are benchmarked against and that enter the combined fit.","marker":"[15]"},{"why":"The earlier data-based extraction of form factor ratios that this paper improves on with new data, symmetry constraints and cross-recoil treatment.","marker":"[30]"},{"why":"Provides the improved Isgur-Wise relations used to organize the $1/m_b$ expansion of the form factor ratios at low recoil.","marker":"[28]"},{"why":"The QCD factorization analysis establishing that hard corrections affect the helicity-suppressed combination but not the individual form factors, which the paper's sum-rule argument is checked against.","marker":"[41]"}],"fun_headline_variants":["B to K* form factors pinned down from decay angular data","Angular data fix B to K* form factor ratios without lattice input","B to K* ratios from data match lattice and sum rule predictions","Low-recoil forward-backward asymmetry stays in line with the Standard Model","An order-one shift in C9 alone cannot explain the P5' anomaly"],"cache_read_input_tokens":0,"weakest_assumption_plain":"Everything rests on the low-recoil operator product expansion: that the decay amplitudes factorize into a polarization-independent short-distance piece times a form factor, up to corrections of only a few percent, and that no sizable right-handed current breaks that factorization.","fun_headline_variants_meta":{"raw":{"variants":["B to K* form factors pinned down from decay angular data","Angular data fix B to K* form factor ratios without lattice input","B to K* ratios from data match lattice and sum rule predictions","Low-recoil forward-backward asymmetry stays in line with the Standard Model","An order-one shift in C9 alone cannot explain the P5' anomaly"]},"model":"selfhosted/deepseek-v4.1-flash","effort":"low","attempts":1,"cost_usd":0.0,"raw_usage":{"total_tokens":1348,"prompt_tokens":981,"completion_tokens":367,"prompt_tokens_details":null,"completion_tokens_details":{"reasoning_tokens":285}},"tokens_in":981,"tokens_out":367,"duration_ms":3968,"image_pages":[],"temperature":1.0,"reasoning_budget":50,"reasoning_tokens":285,"transport_provider":"selfhosted","cache_read_input_tokens":0,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-11-10T10:02:39.632927+00:00","model_set":{"reader":"selfhosted/deepseek-v4.1-flash"},"falsifier":"A lattice or sum-rule determination of $V/A_1$ or $A_2/A_1$ at low recoil landing outside the fit bands shown in the paper's comparison figure, or a measured right-handed-current contribution that spoils the polarization-independent factorization, would undercut the extraction; the dedicated universality observables $H_T^{(1)}$ and $H_T^{(2)}/H_T^{(3)}$ proposed in the cited literature would test the factorization directly.","supporting_citations":[{"cited_title":"Exclusive rare B -> K*e+e- decays at low recoil: controlling the long-distance effects","cited_arxiv_id":"hep-ph/0404250","evidence_quote":"Supplies the low-recoil operator product expansion and the $1/m_b$ corrections that make the amplitude factorization the basis of the whole extraction."},{"cited_title":"Theory of B -> K(*)l+l- decays at high q^2: OPE and quark-hadron duality","cited_arxiv_id":"1101.5118","evidence_quote":"Provides the assessment of higher-order and duality-violating corrections that the authors lean on to argue the universality holds at the few-percent level."},{"cited_title":"The Benefits of B ---> K* l+ l- Decays at Low Recoil","cited_arxiv_id":"1006.5013","evidence_quote":"Defines the short-distance-independent observables and the coefficients $C^{L,R}$ whose cancellation lets form factor ratios be read off the angular data."},{"cited_title":"General Analysis of B -> K^(*) l^+ l^- Decays at Low Recoil","cited_arxiv_id":"1212.2321","evidence_quote":"Supplies the Standard Model values of the short-distance factors $C^{L,R}$ and the framework for the universality observables used to bound right-handed currents."},{"cited_title":"B_{d,s}->rho, omega, K*, phi Decay Form Factors from Light-Cone Sum Rules Revisited","cited_arxiv_id":"hep-ph/0412079","evidence_quote":"The light-cone sum rule form factors whose ratios the paper updates, and whose correlated uncertainties it recomputes."},{"cited_title":"Lattice QCD calculation of form factors describing the rare decays $B \\to K^* \\ell^+ \\ell^-$ and $B_s \\to \\phi \\ell^+ \\ell^-$","cited_arxiv_id":"1310.3722","evidence_quote":"The lattice results on $V$, $A_1$ and $A_2$ that the extracted ratios are benchmarked against and that enter the combined fit."},{"cited_title":"Extracting $B \\to K^*$ Form Factors from Data","cited_arxiv_id":"1204.4444","evidence_quote":"The earlier data-based extraction of form factor ratios that this paper improves on with new data, symmetry constraints and cross-recoil treatment."},{"cited_title":"Symmetry-breaking corrections to heavy meson form factor relations","cited_arxiv_id":"hep-ph/0201298","evidence_quote":"Provides the improved Isgur-Wise relations used to organize the $1/m_b$ expansion of the form factor ratios at low recoil."},{"cited_title":"Symmetry-breaking corrections to heavy-to-light B meson form factors at large recoil","cited_arxiv_id":"hep-ph/0008255","evidence_quote":"The QCD factorization analysis establishing that hard corrections affect the helicity-suppressed combination but not the individual form factors, which the paper's sum-rule argument is checked against."}],"review_version":1}