{"id":"d9c947d1-78c1-4c99-9e36-4a9e2d66038c","arxiv_id":"2606.13088","paper_version":1,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":4.0,"correctness_risk":"high","formal_verification":"none","parameter_count":1,"one_line_summary":"Using coupled-channel one-boson-exchange dynamics the authors predict several K(*) bar D(*) and K(*) D(*) molecular tetraquark candidates and their electromagnetic properties.","lead":"The paper applies the one-boson-exchange model with S-D mixing and coupled channels to predict masses of charmed-strange molecular tetraquarks near K D thresholds and computes their M1 decays and magnetic moments. A smart generalist might read it to see how phenomenological models generate testable predictions for exotic hadrons that current experiments could search for.","discovery_kind":"extension","skeptic_critique":{"model":"grok-4.3","headline":"One-boson-exchange potential parameters (couplings + cutoff) are not shown to reproduce known low-energy K(*)D(*) scattering data or lattice results.","rationale":"The reader's weakest_assumption directly identifies the same model-dependence issue that controls the coupled-channel results. No stronger internal inconsistency appears once the full text is consulted; the concern is therefore unchanged.","tokens_in":1796,"tokens_out":334,"duration_ms":11926,"concrete_test":"Fix the cutoff and couplings exactly as in the paper, compute the S-wave K D and K* D scattering lengths (or low-energy phase shifts) in the single-channel limit, and compare to any available lattice QCD or experimental constraints; a discrepancy larger than ~20% in the scattering length would indicate the kernel is not faithful and would invalidate the coupled-channel binding predictions.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim—that coupled-channel dynamics both deepens existing bindings and produces new states absent in single-channel calculations—rests on solving the Schrödinger equation with an OBE kernel whose overall strength is set by a single cutoff parameter. For the headline to hold, this kernel must correctly encode the attractive/repulsive balance at the relevant momenta; if the chosen couplings or cutoff systematically misrepresent the interaction (e.g., by over- or under-binding in the I=0 or I=1 channels), both the enhancement and the “new states” are artifacts of the parametrization rather than genuine coupled-channel dynamics. The abstract and model description give no independent calibration against phase shifts, scattering lengths, or lattice spectra in these channels.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The manuscript uses the one-boson-exchange (OBE) potential in a coupled-channel Schrödinger equation, including S-D wave mixing, to compute bound-state masses for the K^{(*)}\bar D^{(*)} and K^{(*)}D^{(*)} systems. It reports several loosely bound molecular candidates, asserts that coupled-channel dynamics both deepens existing bindings and produces new states absent in single-channel calculations, and then evaluates M1 radiative widths and magnetic moments of these states within the constituent quark model.","tokens_in":1951,"tokens_out":582,"duration_ms":18375,"significance":"If the OBE kernel is shown to be reliable, the work supplies concrete mass predictions and electromagnetic observables for exotic four-flavor states that could guide experimental searches at facilities such as LHCb or Belle II. The explicit demonstration that coupled channels generate additional bound states would strengthen the case for multichannel dynamics in heavy-light meson systems.","major_comments":[{"comment":"§II (OBE potential construction): the coupling constants g_{K^*Kπ}, g_{D^*Dρ} etc. and the cutoff Λ are introduced without a dedicated calibration subsection that compares the resulting K^{(*)}D^{(*)} scattering lengths or phase shifts to lattice QCD or experimental data. Because the headline claim—that coupled channels generate new states absent in single-channel runs—depends on the attractive/repulsive balance encoded in this kernel, an explicit validation against independent low-energy observables is required.","section":"§II"},{"comment":"Table of bound-state masses (presumably Table I or II): the reported binding energies for the new coupled-channel states are given without error bands arising from variation of Λ within a range that still reproduces known thresholds or from alternative regularization schemes. This makes it impossible to judge whether the appearance of the new states is robust or an artifact of the specific cutoff choice.","section":"Table I/II"}],"minor_comments":[{"comment":"The abstract states qualitative conclusions but supplies no numerical mass values or decay widths; the main text should include a concise summary table of the predicted masses and widths already in the abstract or introduction.","section":"Abstract"},{"comment":"Notation for the channels (K^{(*)}\bar D^{(*)} vs. K^{(*)}D^{(*)}) is clear, but the isospin and C-parity labels for each molecular candidate should be stated explicitly in the mass-spectrum table.","section":"Mass spectra section"}],"recommendation":"major_revision","confidential_remarks":"The manuscript cites earlier OBE studies on related systems; it would be useful to know whether the present parameter set is taken unchanged from those works or re-tuned, as this affects the degree of independent prediction."},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for the careful reading of our manuscript and the constructive comments. We address the major comments point by point below, indicating where revisions will be made.","responses":[{"response":"The coupling constants are standard values adopted from established literature on meson-exchange models for heavy-light systems, as referenced in the manuscript. The cutoff Λ is selected within the conventional range used in OBE studies to generate loosely bound molecular states. We agree that additional context on parameter origins would strengthen the presentation. In the revised manuscript we will add a short paragraph in §II explaining the sources of the couplings and their prior use in related calculations, while noting that a full new lattice calibration for these specific channels lies beyond the present scope.","revision_made":"partial","referee_comment":"[§II] §II (OBE potential construction): the coupling constants g_{K^*Kπ}, g_{D^*Dρ} etc. and the cutoff Λ are introduced without a dedicated calibration subsection that compares the resulting K^{(*)}D^{(*)} scattering lengths or phase shifts to lattice QCD or experimental data. Because the headline claim—that coupled channels generate new states absent in single-channel runs—depends on the attractive/repulsive balance encoded in this kernel, an explicit validation against independent low-energy observables is required."},{"response":"We concur that a sensitivity study is needed to confirm the robustness of the new states. In the revised version we will include an explicit variation of Λ over a physically motivated interval (approximately 0.8–1.2 GeV) and demonstrate that the additional bound states generated by coupled-channel dynamics persist, thereby supplying the requested indication of stability.","revision_made":"yes","referee_comment":"[Table I/II] Table of bound-state masses (presumably Table I or II): the reported binding energies for the new coupled-channel states are given without error bands arising from variation of Λ within a range that still reproduces known thresholds or from alternative regularization schemes. This makes it impossible to judge whether the appearance of the new states is robust or an artifact of the specific cutoff choice."}],"tokens_in":1443,"tokens_out":457,"duration_ms":19080,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"This paper runs the usual one-boson-exchange potential through the K(*)D(*) and K(*)bar D(*) channels, includes S-D mixing and full coupled-channel dynamics, and then uses the resulting wave functions to compute M1 radiative widths and magnetic moments in the constituent quark model. The central claim is that coupled channels both deepen existing bindings and produce new loosely bound states absent from single-channel runs, yielding several candidate molecular tetraquarks.\n\nThe calculation is a straightforward extension of the method already used for other heavy-light systems. Systematically covering these specific flavor combinations and adding electromagnetic observables is a reasonable step; the EM numbers could in principle help experiments distinguish molecular from other interpretations, especially for the four-flavor exotic states.\n\nThe soft spot is the one flagged in the stress test. The OBE couplings and cutoff are free parameters whose overall strength sets the attraction. The abstract and model description give no indication that these were fixed by reproducing known low-energy K D scattering lengths, phase shifts, or lattice spectra. Without that check, both the reported enhancement and the appearance of new states rest on the chosen parametrization rather than on an independently validated kernel. The concern holds up on the available information.\n\nThe work is aimed at readers who follow phenomenological studies of near-threshold exotics in the charmed-strange sector. It supplies concrete mass and decay numbers that could be compared with future data, but it does not move the field beyond the standard OBE framework.\n\nI would send it for peer review. Referees can examine the numerical implementation and press for explicit validation of the potential against independent observables before the new states are treated as robust predictions.","headline":"Standard OBE plus coupled-channel scan for K(*)D(*) molecules that adds EM observables, but the kernel parameters receive no calibration to scattering or lattice data so the new states may be tuning artifacts.","tokens_in":2452,"tokens_out":419,"would_cite":false,"duration_ms":20032,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.3","headline":"Coupled-channel dynamics generates new loosely bound K(*)D(*) molecular tetraquarks absent from single-channel calculations.","keywords":["molecular tetraquarks","one-boson-exchange","coupled channels","charmed-strange hadrons","mass spectra","radiative decays","magnetic moments"],"falsifier":"Experimental searches that either detect or rule out narrow states at the specific masses and with the predicted M1 decay patterns near the K(*)D(*) thresholds.","tokens_in":2664,"feed_emoji":"⚛","tokens_out":634,"duration_ms":13725,"temperature":0.7,"pith_summary":"The paper examines the mass spectra of charmed-strange states near the K(*) bar D(*) and K(*) D(*) thresholds by solving the one-boson-exchange potential in a coupled-channel framework that includes S-D wave mixing. It shows that the inter-channel couplings both deepen existing bindings and create additional shallow bound states that single-channel treatments miss. Electromagnetic quantities such as M1 radiative widths and magnetic moments are then computed from the resulting wave functions inside the constituent quark model, providing observables that can distinguish molecular interpretations from other structures. The work singles out the four-flavor exotic combinations as especially clear targets for experiment.","feed_headline":"Coupled channels create new molecular tetraquarks near K D thresholds","feed_subtitle":"Dynamics generate loosely bound states absent in single-channel calculations; electromagnetic widths help confirm their nature.","key_machinery":"One-boson-exchange potential solved in a coupled-channel Schrödinger equation with S-D wave mixing","core_discovery":"The one-boson-exchange model with explicit coupled-channel effects and S-D mixing yields several K(*) bar D(*) and K(*) D(*) molecular tetraquarks as loosely bound states. The coupled-channel dynamics is essential: it strengthens binding where single-channel solutions already exist and produces new bound states where they do not. Electromagnetic decay widths and magnetic moments calculated from the spatial wave functions serve as discriminants for the molecular nature of these states.","pith_inferences":["Similar coupled-channel enhancements may appear in other heavy-light meson-meson systems near thresholds.","If confirmed, the states would supply new benchmarks for testing effective potentials in the charm-strange sector.","Non-observation of the predicted electromagnetic signatures would constrain the size of the cutoff parameters used in the model."],"forward_implications":["Several new molecular candidates appear only when channels are allowed to couple.","Electromagnetic observables calculated from the wave functions can distinguish molecular tetraquarks from conventional states.","The four-flavor exotic combinations \bar c \bar s u d are predicted as especially clean molecular candidates.","Mass spectra and decay widths are obtained for both charged and neutral members of the multiplets."],"fun_headline_variants":["Coupled channels bind new K bar D molecular tetraquarks","One-boson exchange yields K(*)D(*) loosely bound states","S-D mixing and channels create extra tetraquark candidates","Electromagnetic widths distinguish charmed-strange molecules","Mass spectra show K(*) bar D(*) molecular states near thresholds"],"cache_read_input_tokens":2112,"weakest_assumption_plain":"The chosen coupling constants and cutoff parameters in the one-boson-exchange potential correctly reproduce the low-energy meson-meson scattering in the relevant channels.","fun_headline_variants_meta":{"raw":{"variants":["Coupled channels bind new K bar D molecular tetraquarks","One-boson exchange yields K(*)D(*) loosely bound states","S-D mixing and channels create extra tetraquark candidates","Electromagnetic widths distinguish charmed-strange molecules","Mass spectra show K(*) bar D(*) molecular states near thresholds"]},"model":"grok-4.3","cost_usd":0.004487,"raw_usage":{"total_tokens":2259,"prompt_tokens":713,"num_sources_used":0,"completion_tokens":79,"cost_in_usd_ticks":44874500,"prompt_tokens_details":{"text_tokens":713,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":1467,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":713,"tokens_out":79,"duration_ms":9840,"temperature":1.0,"reasoning_tokens":1467,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-06-27T06:41:02.039735+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"Experimental searches that either detect or rule out narrow states at the specific masses and with the predicted M1 decay patterns near the K(*)D(*) thresholds.","supporting_citations":[],"review_version":1}