{"id":"cda0c12a-dcc1-44e7-b18d-b9bab3ed6151","arxiv_id":"2607.05335","paper_version":1,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":6.0,"correctness_risk":"unknown","formal_verification":"none","parameter_count":5,"one_line_summary":"ANTARES Galactic Ridge neutrino observations constrain DM-nucleon elastic scattering cross sections down to keV-scale DM masses via cosmic ray–dark matter deep inelastic scattering.","lead":"This paper uses neutrino observations from the Galactic Ridge to set new upper limits on how strongly light dark matter interacts with ordinary matter, extending sensitivity down to keV-scale dark matter masses. A smart generalist might read it because it demonstrates a new way to search for dark matter using neutrino telescopes, a channel that probes regions other experiments cannot reach.","discovery_kind":"new_application","skeptic_critique":{"model":"glm-5.2","headline":"The CR transport model choice (γ-optimized Min vs. Base-Minimal) is the dominant systematic, and the paper's claim of probing new parameter space at keV-scale masses depends on the γ-optimized model being closer to reality.","rationale":"The reader correctly identified the single most load-bearing concern: the dependence on the γ-optimized Min CR transport model, which the paper itself shows weakens limits by ~10× when replaced with the Base-Minimal model. This is the dominant systematic, exceeding the DM profile uncertainty (factor 2-3), PDF uncertainty (≤30%), and neutrino yield model dependence.\n\nThe paper handles this concern responsibly: it presents both CR models in the Supplemental Material, uses the 99% C.L. (most conservative) ANTARES limits, does not subtract astrophysical backgrounds (further conservative), and provides extensive systematic variation studies. The γ-optimized model has independent support from Fermi-LAT gamma-ray data and IceCube neutrino observations. These are real mitigating factors.\n\nThe verdict of CONDITIONAL with MODERATE confidence is appropriate. The condition is that the γ-optimized Min model is a reasonable description of the inner Galaxy CR distribution — a condition the paper cannot fully verify but which is supported by external multi-messenger data. The lack of reproducible code is a legitimate secondary concern but does not affect the soundness of the argument as presented.\n\nI do not adjust the verdict because: (1) the reader already weighted this concern appropriately in setting CONDITIONAL rather than ACCEPT; (2) the paper's own systematic treatment is thorough and transparent; (3) the ANTARES-based limits are defensible as a legitimate new constraint even under the conservative CR model. The IceCube-Gen2 and KM3NeT projections are correctly flagged as indicative rather than rigorous, which the reader also noted.","tokens_in":19719,"tokens_out":6453,"duration_ms":141535,"concrete_test":"Recompute the limits in Fig. 2 using the Base-Minimal CR model (the most conservative scenario shown in Fig. 6) and overlay all existing constraints (Lyman-α, MW satellites, direct detection, CRDM). If the Base-Minimal limits at m_χ ≲ 10 keV still fall below existing constraints, the headline claim of probing new parameter space is robust to the CR model choice. If they do not — i.e., if the Base-Minimal limits are already excluded by Lyman-α or MW satellite bounds at these masses — then the claim of 'previously unexplored parameter space' at the lowest masses depends entirely on the γ-optimized model being correct, and the headline should be qualified accordingly.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The reader correctly identifies the most load-bearing concern. The central claim — that ANTARES Ridge neutrino observations constrain DM-nucleon scattering into previously unexplored keV-scale parameter space — depends on the predicted neutrino flux from CR-DM interactions (Eq. 1), which is directly proportional to the CR density in the Galactic Ridge. The paper uses the γ-optimized Min transport model (Ref. [33, 39]) as its fiducial case, which features a spatially non-uniform diffusion coefficient that hardens the CR spectrum and increases the CR density toward the Galactic Center. The Supplemental Material (Fig. 6) shows that switching to the Base-Minimal (uniform diffusion) model weakens the cross-section limits by approximately an order of magnitude at low DM masses (m_χ ≲ 0.1 MeV). This is the single largest systematic uncertainty in the analysis.\n\nThe γ-optimized model is physically motivated — it reproduces the Fermi-LAT observation of progressive spectral hardening of diffuse γ-ray emission toward the Galactic Center — and the paper notes it is also consistent with IceCube Galactic Plane neutrino hints. This provides some independent support. However, the model is not independently verified by this paper, and the inner Galaxy CR transport remains an active research area with degeneracies between CR transport parameters, source distributions, and gas density modeling. The concern is not that the γ-optimized model is wrong, but that the headline claim of probing 'previously unexplored parameter space' at the lowest DM masses may not survive if the more conservative Base-Minimal model is adopted. At m_χ ~ 1 keV, the γ-optimized Min limits reach ~10^{-35} cm² (m_V = 5 GeV), while the Base-Minimal limits would be ~10^{-34} cm² — still potentially competitive with cosmological constraints (~10^{-29} cm² from Lyman-α at 10 keV), but the margin is narrower.\n\nThe MadGraph5/Pythia8 neutrino yield calculation and the PDF uncertainties (Supplemental Material, Fig. 8) a","agreement_with_reader":"agree"},"referee_report":{"model":"glm-5.2","summary":"This Letter proposes using Galactic Ridge neutrino observations from ANTARES to constrain dark matter (DM)–nucleon elastic scattering cross sections at sub-GeV masses. The mechanism is deep inelastic scattering of cosmic rays (CRs) off DM in the Galactic halo, producing secondary neutrinos from meson decay. The predicted neutrino flux (Eq. 1) is computed using a line-of-sight integral over the Ridge region, with CR densities from the gamma-optimized Min transport model and an NFW DM profile. The neutrino energy spectrum per interaction is obtained via a MadGraph5 + Pythia 8 Monte Carlo pipeline. Upper limits on the coupling G_D are derived by requiring the predicted flux not exceed ANTARES 99% C.L. upper limits in any energy bin (Eq. 3), then converted to sigma_el via Eq. 4. The main results (Fig. 2) show constraints spanning m_chi from ~1 keV to ~1 GeV for two benchmark mediator masses, with projections for IceCube-Gen2 and KM3NeT. Systematic uncertainties from CR transport, DM profile, PDFs, and cross-section parameterization are explored in the Supplemental Material.","tokens_in":20544,"tokens_out":1296,"duration_ms":140611,"significance":"The paper opens a genuinely new observational channel for light DM: using Galactic Center neutrinos to constrain DM-nucleon scattering. The methodology is well-implemented: the line-of-sight integral, the Monte Carlo pipeline for dN_nu/dE_nu, and the limit-setting procedure are all standard and correctly executed. The systematic uncertainty treatment is commendable in scope — the authors bracket CR transport uncertainties (gamma-optimized Min/Max vs. Base-Minimal, Fig. 6), DM profile choices (NFW, Burkert, Einasto, Moore, Fig. 7), PDF systematics (Fig. 8), and cross-section model dependence (Fig. 4). The use of realistic spatially-dependent CR maps, rather than a constant CR density, is a substantive improvement over prior work. The falsifiable predictions for next-generation detectors (IceCube-Gen2, KM3NeT) add value. The central claim — that these observations probe previously unexplored keV-scale parameter space — is defensible but, as discussed below, depends on the fiducial CR transport model in a way that should be more transparently reflected in the headline statements.","major_comments":[{"comment":"Main text, paragraph following Eq. (1): the paper states that astrophysical uncertainties 'introduce an uncertainty of a factor of a few,' but the Supplemental Material (Fig. 6) shows that switching from the gamma-optimized Min model to the Base-Minimal scenario weakens constraints by approximately an order of magnitude at low DM masses (m_chi < 0.1 MeV). This is the single largest systematic in the analysis and is load-bearing for the claim of probing 'previously unexplored parameter space' at keV-scale masses. The 'factor of a few' statement in the main text appears to refer to the DM profile variation (Fig. 7) and the spread between gamma-optimized Min and Max, but it does not encompass the Base-Minimal comparison. The main text should explicitly acknowledge the order-of-magnitude systematic from CR transport model choice and clarify which uncertainties are included in the 'factor ofa","section":null}],"minor_comments":[{"comment":"The abstract states limits 'extend down to keV-scale masses' without qualification. Given the order-of-magnitude systematic from CR transport at the lowest masses, a brief qualifier (e.g., 'under the gamma-optimized CR transport model') would be appropriate.","section":null},{"comment":"Section 'Existing Constraints': the discussion of N_eff constraints (Ref. [62]) notes cross sections bounded down to 10^-49 cm^2 for masses below a few MeV, but does not show these in Fig. 2. A brief explanation of why N_eff bounds are excluded from the figure, or inclusion of them, would help the reader assess the novelty for keV-scale DM.","section":null},{"comment":"Supplemental Material, cross-section comparison (right panel of Fig. 4): the Kamae and AAfrag parameterizations are scaled by 0.1, but the physical motivation for this specific scaling factor is not stated. A one-sentence justification would be appropriate.","section":null},{"comment":"Figure 1 caption: 'am DM' appears twice and should be 'm_DM'. Similarly, 'am DM = 10 MeV' and 'am DM = 10 keV' should be 'm_DM'.","section":null},{"comment":"The projected KM3NeT sensitivity uses a factor of 3.5 (sqrt(10) rounded up), while the text states the effective area is 10-100 times larger than ANTARES. Using only the lower bound is conservative, but the range of possible improvement (3.5 to ~10) should be noted for context.","section":null},{"comment":"Reference [32] is cited as 'JHEAp 53, 100565 (2026)' with a 2025 arXiv number; the year consistency should be checked.","section":null},{"comment":"The paper would benefit from a brief statement in the Conclusions acknowledging that the gamma-optimized CR model, while supported by gamma-ray and IceCube data, is not yet independently confirmed, and that the Base-Minimal scenario provides a conservative lower bound on the achievable constraints.","section":null}],"recommendation":"minor_revision","confidential_remarks":"The reader's report and stress-test note correctly identify the CR transport model choice as the dominant systematic. On reading the paper, I find this concern partially but not fully addressed: the Supplemental Material is thorough, but the main text understates the systematic ('factor of a few') when the actual spread including Base-Minimal is an order of magnitude. This is a presentation issue rather than a substantive error — the analysis itself is sound and the systematic is properly bracketed. The paper is a good fit for a Letter: it opens a new probe, the methodology is solid, and the systematic treatment is above average for the subfield. I recommend minor revision with the main text corrected to accurately represent the CR transport systematic."},"author_rebuttal":{"model":"glm-5.2","summary":"We thank the referee for a careful and constructive report. We address the major comment below.","responses":[{"response":"The referee is correct. The statement in the main text that astrophysical uncertainties 'introduce an uncertainty of a factor of a few' was intended to refer to the variation among the gamma-optimized Min/Max models and the DM profile choices (NFW vs. Burkert, Einasto, Moore), which indeed produce factor-of-few variations. However, this statement as written does not encompass the comparison to the Base-Minimal CR transport scenario, which, as shown in Fig. 6 of the Supplemental Material, weakens the constraints by approximately an order of magnitude at m_chi < 0.1 MeV. This is the largest single systematic in the analysis and is load-bearing for our claim of probing previously unexplored parameter space at keV-scale masses. We will revise the main text to explicitly acknowledge this order-of-magnitude systematic from CR transport model choice and to clarify which uncertainties are included in the 'factor of a few' statement (namely, the spread among gamma-optimized models and DM profile variations). We will also add a sentence noting that the Base-Minimal scenario, which does not reproduce the gamma-ray data toward the Galactic Center, represents a conservative lower bound on the CR density and correspondingly weakens the constraints by up to an order of magnitude at the lowest masses. This revision will make the headline claims more transparent without altering our central conclusion: even under the conservative Base-Minimal scenario, the constraints remain competitive with existing bounds across much of the mass range, and the gamma-optimized models — which are favored by multi-messenger gamma-ray and neutrino data — provide the stronger limits we quote as our fiducial results.","revision_made":"yes","referee_comment":"Main text states astrophysical uncertainties introduce 'a factor of a few,' but Supplemental Material Fig. 6 shows switching from gamma-optimized Min to Base-Minimal weakens constraints by ~order of magnitude at low DM masses (m_chi < 0.1 MeV). The 'factor of a few' statement does not encompass the Base-Minimal comparison and should be corrected, especially given its importance for the claim of probing previously unexplored parameter space at keV-scale masses."}],"tokens_in":19332,"tokens_out":702,"duration_ms":36132,"standing_objections":[]},"desk_editor":{"model":"glm-5.2","letter":"Here's the short version: this paper derives 99% C.L. upper limits on DM-nucleon elastic scattering using ANTARES Galactic Ridge neutrino observations, applied to CR-DM deep inelastic scattering for the first time. The methodology is sound and the systematic exploration is thorough. The main soft spot is the dependence on the γ-optimized CR transport model, which the authors themselves show weakens the limits by an order of magnitude under a more conservative diffusion setup. The paper deserves a serious referee. What's genuinely new is the application to ANTARES Ridge data — nobody has used Galactic Center neutrinos to constrain CR-DM interactions before. The MadGraph5/Pythia8 pipeline for computing neutrino yields from CR-DM DIS is a step up from the constant-cross-section or scaled p-p parameterizations used in prior work, and the supplemental comparison (Fig. 4, right panel) shows these choices matter: the dynamical model can differ from the Kamae/AAfrag baselines by 2-3 orders of magnitude at low neutrino energies. The limit-setting procedure (Eq. 3) is standard and the treatment of astrophysical uncertainties is honest — they check DM profiles (NFW, Burkert, Einasto, Moore), CR transport scenarios, PDF sets, and cross-section parameterizations. The PDF analysis (Fig. 8) shows their benchmark choice is the most conservative among the sets tested, which is the right direction for an upper-limit analysis. The dominant systematic is the CR transport model. The γ-optimized Min model is physically motivated — it reproduces Fermi-LAT spectral hardening toward the Galactic Center and is consistent with IceCube Galactic Plane hints — but it's not independently verified here, and inner Galaxy CR transport remains an active research area with known degeneracies. Fig. 6 in the supplement shows the Base-Minimal (uniform diffusion) scenario weakens the low-mass limits by roughly an order of magnitude. The headline claim of probing 'previously unexplored parameter space' at keV scales is safest under the γ-optimized model; under the conservative model the limits are still below cosmological constraints (Lyman-α, MW satellites at ~10^{-29} cm²), but the margin narrows. The authors are transparent about this, which is good, but the abstract and conclusions could state more clearly that the most aggressive limits depend on a specific propagation model. Two minor points: no code or data is provided for reproducibility, and the IceCube-Gen2/KM3NeT projections use rough effective-area scalings rather than full detector simulations — fine for indicating potential, but they shouldn't be read as rigorous sensitivity estimates. Neither of these undermines the ANTARES-based result, which stands on its own. This is a well-executed paper that opens a genuinely new observational channel for light DM. The core result is defensible and the systematic treatment is above average for the field. Recommend sending to a serious referee who can scrutinize the CR transport model dependence and whether the claims are appropriately qualified throughout.","headline":"New ANTARES Galactic Ridge neutrino limits on sub-GeV DM-nucleon scattering; solid methodology but limits hinge on CR transport model choice","tokens_in":20638,"tokens_out":1558,"would_cite":true,"duration_ms":69293,"reading_group":"yes","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":["95.85.Ry","95.35.+d","98.35.Gi"],"model":"glm-5.2","headline":"Neutrino telescope data bounds dark matter down to keV masses","keywords":[],"falsifier":"If the cosmic-ray density or spectral hardness in the Galactic Ridge is significantly lower than predicted by the gamma-optimized transport model—for instance, if the observed gamma-ray and neutrino emission is explained by a different mechanism—then the predicted DM-induced neutrino flux would be overestimated and the derived cross-section limits would be too stringent. The Base-Minimal uniform-diffusion scenario already demonstrates roughly an order-of-magnitude weakening at low masses, and any future revision of inner-Galaxy cosmic-ray transport that reduces the predicted high-energy proton","tokens_in":19895,"feed_emoji":"🔭","tokens_out":1084,"duration_ms":101172,"temperature":0.7,"pith_summary":"This paper proposes that high-energy neutrinos observed from the Galactic Ridge by the ANTARES telescope can be used to constrain light dark matter (DM) in the sub-GeV to keV mass range, a regime where traditional direct detection experiments lose sensitivity. The core mechanism is deep inelastic scattering between Galactic cosmic rays and ambient DM particles in the inner Galaxy: when a cosmic-ray proton collides with a DM particle, the interaction produces mesons that decay into neutrinos. Because both cosmic-ray density and DM density are highest toward the Galactic Center, this region produces the strongest expected signal. The authors compute the predicted neutrino flux using a detailed cosmic-ray transport model calibrated to gamma-ray data, a Monte Carlo pipeline for the particle-level scattering and hadronization, and a standard Navarro-Frenk-White dark matter density profile. They then require that the predicted DM-induced neutrino flux does not exceed the observed 99% confidence-level upper limits from ANTARES in any energy bin. This procedure yields upper limits on the DM-nucleon elastic scattering cross section that extend down to keV-scale DM masses, probing parameter space that is complementary to direct detection, cosmological, and other indirect searches. The paper also projects that next-generation neutrino telescopes (IceCube-Gen2 and KM3NeT) will improve these limits by roughly an order of magnitude or more.","feed_headline":"Neutrino telescope data bounds dark matter down to keV masses","feed_subtitle":"Cosmic rays colliding with dark matter in the Galactic Center produce neutrinos that ANTARES already constrains, with IceCube-Gen2 and KM3Ne","key_machinery":"The key machinery is the line-of-sight integral (Eq. 1) that convolves the Galactic dark matter density, the spatially-dependent cosmic-ray distribution from the gamma-optimized Min transport model, and the deep inelastic scattering cross section and neutrino yield from a MadGraph5 + Pythia 8 Monte Carlo pipeline. The coupling bound is set by the bin-by-bin comparison with ANTARES 99% C.L. upper limits (Eq. 3), then converted to the elastic DM-nucleon cross section via the reduced-mass relation (Eq. 4).","core_discovery":"The central result is a set of 99% confidence-level upper limits on the DM-nucleon elastic scattering cross section derived entirely from Galactic Center neutrino observations. By requiring that the neutrino flux produced by cosmic-ray dark matter deep inelastic scattering not exceed ANTARES measurements of the Galactic Ridge in any energy bin, the authors obtain constraints valid for DM masses from approximately 1 keV up to nearly 1 GeV. These limits are derived using a vector-mediator simplified model with benchmark mediator masses of 100 MeV and 5 GeV, and the authors demonstrate that the neutrino yield is computed from first-principles particle-level simulations rather than the constant-","pith_inferences":[],"forward_implications":["Next-generation neutrino telescopes IceCube-Gen2 and KM3NeT could improve these cross-section limits by at least an order of magnitude, potentially reaching sensitivity competitive with collider-based searches for light dark matter mediators.","A joint analysis combining Galactic neutrino data with future TeV-PeV gamma-ray observations of the Galactic Center could disentangle a potential dark matter signal from astrophysical backgrounds, since the same cosmic-ray DM interactions produce a correlated neutral-pion gamma-ray flux.","The method is sensitive to the dark matter density profile in the innermost Galaxy; if DM spikes exist near the supermassive black hole, the constraints could strengthen significantly, while cored profiles would weaken them by up to an order of magnitude.","The approach is largely insensitive to the spin or mediator type of the DM candidate, since the large cosmic-ray energies compensate for velocity suppressions that affect low-velocity scattering, making this a broadly applicable probe across DM model space."],"fun_headline_variants":["ANTARES Galactic Center neutrinos constrain sub-GeV dark matter scattering","Cosmic ray–dark matter collisions produce neutrino signal bounded by ANTARES","Neutrino telescopes set 99% C.L. limits on keV-scale dark matter cross section","Galactic Ridge neutrino data restricts light dark matter-nucleon interactions","ANTARES observations cap dark matter scattering from keV to GeV masses"],"cache_read_input_tokens":0,"weakest_assumption_plain":"The derived limits depend on the gamma-optimized Min cosmic-ray transport model, which uses a spatially non-uniform diffusion coefficient tuned to reproduce Fermi-LAT gamma-ray data from the inner Galaxy. The paper itself shows that switching to a uniform-diffusion model weakens the constraints by roughly an order of magnitude at low DM masses. The correctness of this specific propagation model in the Galactic Center is not independently verified here and remains an open ast","fun_headline_variants_meta":{"raw":{"variants":["ANTARES Galactic Center neutrinos constrain sub-GeV dark matter scattering","Cosmic ray–dark matter collisions produce neutrino signal bounded by ANTARES","Neutrino telescopes set 99% C.L. limits on keV-scale dark matter cross section","Galactic Ridge neutrino data restricts light dark matter-nucleon interactions","ANTARES observations cap dark matter scattering from keV to GeV masses"]},"model":"glm-5.2","effort":"high","cost_usd":0.0,"raw_usage":{"total_tokens":592,"prompt_tokens":486,"completion_tokens":106,"prompt_tokens_details":null},"tokens_in":486,"tokens_out":106,"duration_ms":47621,"temperature":1.0,"reasoning_tokens":null,"cache_read_input_tokens":0,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-07-07T16:30:39.515664+00:00","model_set":{"reader":"glm-5.2"},"falsifier":"If the cosmic-ray density or spectral hardness in the Galactic Ridge is significantly lower than predicted by the gamma-optimized transport model—for instance, if the observed gamma-ray and neutrino emission is explained by a different mechanism—then the predicted DM-induced neutrino flux would be overestimated and the derived cross-section limits would be too stringent. The Base-Minimal uniform-diffusion scenario already demonstrates roughly an order-of-magnitude weakening at low masses, and any future revision of inner-Galaxy cosmic-ray transport that reduces the predicted high-energy proton","supporting_citations":[],"review_version":1}