{"id":"3ef0058f-6c33-4878-a103-990aca4141ad","arxiv_id":"2508.11891","paper_version":2,"verdict":"CONDITIONAL","confidence":"MODERATE","novelty_score":5.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":6,"one_line_summary":"Cosmic-ray boosted supernova neutrinos could be detectable in optimistic astrophysical scenarios and yield a bound of about 30 TeV on the extra-dimensional scale.","lead":"Cosmic-ray protons scattering off the roughly ten-million-electronvolt neutrinos emitted by supernovae can accelerate those neutrinos to extremely high energies. This paper calculates the resulting fluxes, finds that optimistic sources could be visible to future telescopes, and derives a bound on extra-dimensional physics from the absence of such events.","discovery_kind":"new_application","skeptic_critique":{"model":"deepseek-v4-flash","headline":"The M*>30 TeV bound from TXS 0506+056 rests on an unmeasured UHE proton luminosity and spectral index; at the soft end of the allowed range the excluded scale is not robust.","rationale":"After reading the paper and the reader's verdict, the mechanism-level calculation (Eq. 3 plus SM cross sections) is transparent and the SM flux predictions for the specific sources in Table I are conservative in the sense that they lie well below current limits. The claim that is load-bearing for the paper's novelty is the M* ≳ 30 TeV bound, and that bound inherits every astrophysical assumption in the TXS flux. The reader's weakest_assumption identifies exactly this: the unmeasured UHE proton luminosity and spectral index. My concrete test would settle it by recomputing the exclusion at the soft edge of the allowed α range and a lower L_CR. I do not see an internal inconsistency in the cross-section treatment, though a full recast of ANITA's exposure (including Earth attenuation for enhanced σ) would be a useful additional check. The novelty claim 'first obtained with astrophysical high-energy neutrino data' also needs qualification relative to the CNB-boost literature and ref [69], but that does not change the correctness of the mechanism. The verdict CONDITIONAL remains appropriate, and no adjustment is needed.","tokens_in":11045,"tokens_out":23870,"duration_ms":271170,"concrete_test":"Recompute the TXS M* exclusion with the same code and assumptions but set α = 2.4 (soft edge of the IceCube time-dependent range in [7]) and L_CR = 10^48 erg/s, leaving R_SN = 10 yr^-1, d = 1762 Mpc, and T_p^max fixed. If the derived lower limit on M* falls below ~10 TeV or the ANITA curve no longer intersects the predicted flux, the headline bound is not robust to the allowed astrophysical parameter space. Also run α = 1.8 and L_CR = 10^49 to confirm the upper edge; the sensitivity of the bound to these inputs is the test.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central new-physics claim is the exclusion M* ≳ 30 TeV from ANITA's non-observation of boosted supernova neutrinos from TXS 0506+056 (Fig. 3). This exclusion inherits the TXS flux calculation, which assumes the cosmic-ray luminosity L_CR ≈ 10^49 erg/s (Table I) is carried by protons in an unbroken power law dΦ_p/dT_p ∝ T_p^{-α} up to T_p^max = 5×10^11 GeV, with α in the IceCube time-dependent range 1.8–2.4. The flux at ANITA-relevant energies is produced by protons at T_p ∼ 10^8–10^10 GeV, where the spectrum is not directly measured for TXS. Fig. 2 (right) shows that varying α across that range changes the TXS boosted flux by orders of magnitude at Eν ≳ 10^8 GeV. Since the M* curves in Fig. 3 are proportional to this flux (after the σ_BSM/σ_SM detection-side recast), choosing α = 2.4 or a more conservative L_CR = 10^48 erg/s will lower the expected signal enough that the ANITA limit no longer excludes M* = 30 TeV. The paper's own Conclusions acknowledge the 'strong dependence on the cosmic-ray energy spectrum'; the bound is therefore an upper-limit-driven forecast rather than a robust measurement. The mechanism calculation itself is standard and not in question.","agreement_with_reader":"agree"},"referee_report":{"model":"deepseek-v4-flash","summary":"The manuscript proposes a new mechanism for high-energy neutrino production: cosmic-ray protons scattering with the ~10 MeV neutrinos emitted by core-collapse supernovae boost those neutrinos to energies of 10^6–10^10 GeV. The authors compute the resulting flux for a set of external galaxies and for optimistic benchmark parameters, finding that under the latter the flux could be within reach of current or near-future neutrino telescopes, while for specific sources with estimated parameter bounds the predicted fluxes lie roughly 4–8 orders of magnitude below current sensitivity. The paper then considers extra-dimensional new physics in which the proton-neutrino cross section grows as s^2 above a scale M*, and uses the non-observation of ultra-high-energy neutrinos from TXS 0506+056 by ANITA to derive M* ≳ 30 TeV, which the authors describe as the first bound on this scale from astrophysical high-energy neutrino data.","tokens_in":11345,"tokens_out":5906,"duration_ms":71157,"significance":"If the calculation is sound, the proposed mechanism is a genuinely new contribution to the discussion of high-energy neutrino production in astrophysical sources, complementing the usual pp and pγ channels and the previously studied cosmic-neutrino-background boosting. The paper is transparent about its parameter choices, uses standard cross-section inputs (including NUANCE for deep inelastic scattering), and the resulting flux predictions are falsifiable in the sense that they can be compared with existing and projected limits. The derived M* bound, if robust, would be competitive with the SN1987A graviton-emission bound and would demonstrate a new use of high-energy neutrino telescopes. However, the significance of the headline new-physics result is substantially moderated by its strong dependence on source parameters that are not directly measured at the relevant ultra-high energies, as detailed below.","major_comments":[{"comment":"The central new-physics claim, M* ≳ 30 TeV from the ANITA non-observation of TXS 0506+056, is not robust against the assumed cosmic-ray spectrum and luminosity. The predicted boosted flux at Eν ≳ 10^8 GeV is produced by protons with T_p ∼ 10^8–10^10 GeV, where the TXS spectrum is not directly measured; the calculation adopts an unbroken proton power law with L_CR ≈ 10^49 erg/s and α in the range 1.8–2.4 taken from time-dependent IceCube analyses. The right panel of Fig. 2 shows that varying α across this allowed range changes the flux by orders of magnitude, and the paper itself acknowledges the strong spectral-index dependence in the Conclusions. Consequently, for α = 2.4 or a lower conservative L_CR, the ANITA limit would no longer exclude M* = 30 TeV. The bound should therefore be either recast as a conditional sensitivity forecast or supplemented with a conservative exclusion derived from the softest allowed spectrum and lowest plausible luminosity.","section":"Upper limits on the ultra-high energy proton-neutrino cross section, Fig. 3"},{"comment":"Equation (3) appears to omit the integration over the angle between the cosmic-ray proton direction and the supernova neutrino direction. The scattering rate per target neutrino is proportional to ∫dΩ (dΦp/dT_p dΩ) σνp(s(θ)), where the center-of-mass energy depends on the relative angle through s = m_p^2 + 2Eν(E_p − p_p cosθ). As written, the equation uses dΦp/dT_p dΩ without specifying the angle or performing the dΩ integral. This ambiguity matters particularly for the blazar model of Eq. (5), which is explicitly angle-dependent through μ, and it affects the normalization and energy distribution of the TXS flux used in the M* bound. The authors should specify the angular prescription (e.g., head-on approximation, isotropic averaging, or full angle integration) or include the missing integral.","section":"Boosted supernova neutrino flux, Eq. (3)"},{"comment":"The 'potentially detectable flux' statement in the abstract and the left panel of Fig. 1 is an illustrative scenario that combines parameter values taken from different objects: L_CR = 10^49 erg/s is inferred for TXS 0506+056, R_SN = 10 yr^-1 is inferred for Arp 220, and d = 3 Mpc corresponds to nearby starburst galaxies. No known source simultaneously realizes these values, as the right panel of Fig. 1 demonstrates for the four sources with available parameter estimates. The text does label this as optimistic, but the abstract-level claim should more clearly state that this is a parameter-space illustration rather than a prediction for any specific object, so that readers do not take the detectability claim as applying to an actual known source.","section":"Left panel of Fig. 1 and Abstract"}],"minor_comments":[{"comment":"The notation RSNν in Eq. (2) appears to be a typo for R_SN, and the range '0.1−10 yr−1' should use consistent spacing and units.","section":"Eq. (2) and surrounding text"},{"comment":"The quantities γ'_min,p, γ'_max,p, D, β_B, and μ are used in Eq. (5) but are only partially defined in the text; a complete definition of each symbol and the angular variable μ would improve reproducibility.","section":"Eq. (5)"},{"comment":"The sentence immediately following Table I contains the duplicated phrase 'in this in this work'; this should be corrected.","section":"Table I"},{"comment":"The machine-readable text of the figure captions renders the supernova-rate unit as 'yr□1'; if this reflects the actual manuscript, the superscript minus sign should be corrected.","section":"Fig. 1 and Fig. 2 captions"},{"comment":"The phrase 'the first one obtained with astrophysical high-energy neutrino data' should be checked carefully against the existing literature on ultra-high-energy neutrino cross-section limits, since Ref. [69] and related work may already derive constraints from high-energy neutrino observations.","section":"Conclusions"}],"recommendation":"major_revision","confidential_remarks":"The manuscript's headline result is the M* ≳ 30 TeV bound from TXS 0506+056 and ANITA, but this bound is not robust to the allowed range of the unmeasured ultra-high-energy proton spectrum. I would encourage the editor to require either a conservative exclusion that survives for the softest spectrum and lowest luminosity, or a clear reframing as a sensitivity forecast. The mechanism itself is physically interesting and the SM flux calculation is largely standard, so the paper is likely salvageable through revision rather than rejection."},"author_rebuttal":null,"desk_editor":{"model":"deepseek-v4-flash","letter":"Colleague,\n\nThe headline: Herrera and Horiuchi take the cosmic-ray boosting mechanism already applied to the cosmic neutrino background and point it at supernova neutrinos. That application is new, the flux calculation is transparent, and the paper is honest about the big gap between the optimistic benchmarks and what known sources actually support. The flashy result—M* > 30 TeV from ANITA non-observation of TXS 0506+056—does not survive contact with the spectral-index uncertainty. The paper itself shows this in Fig. 2 and acknowledges it in the conclusions, but the abstract and conclusions still present the bound as a solid new constraint.\n\nWhat is genuinely good: the flux integrals and cross-section treatment are standard; they use NUANCE for DIS and match the high-energy behavior; the parameter dependence is displayed rather than hidden. The Table I comparison is useful: for M82, NGC 253, NGC 1068, Arp 220, and TXS with inferred limits, the boosted flux lands 4–8 orders below current sensitivity. That is an honest negative result for the mechanism in known sources, and it is the most solid part of the paper. The self-citations to the CnuB boost program are appropriate; the authors are extending their own earlier work, and the extra-dimensional parametrization is properly attributed to [39,40,69].\n\nThe weak spot is the M* limit. It assumes TXS's ultra-high-energy proton luminosity is about 1e49 erg/s in an unbroken power law with alpha between 1.8 and 2.4 up to 5e11 GeV. Neither the luminosity nor the spectral index at 1e8–1e10 GeV is measured for TXS; IceCube's time-dependent fit is for the neutrino spectrum, not the proton spectrum. Fig. 2 (right) shows that alpha=2.4 instead of 1.8 drops the boosted flux by orders of magnitude at ANITA-relevant energies, and a lower L_CR would do the same. So the claimed exclusion M* > 30 TeV is better read as an upper-limit-driven forecast: if the source is that bright in UHE protons with a hard spectrum, then ANITA excludes 30 TeV. The 'first bound from astrophysical high-energy neutrino data' line overstates it, especially since the connection to the CnuB-boost program should be checked against earlier work. The paper does include the caveat about strong dependence on the cosmic-ray spectrum, so this is a framing problem rather than a hidden error.\n\nVerdict: the mechanism calculation is fine and the negative results for known sources are worth publishing. The M* bound needs to be qualified or reframed in a revision. I would send this to peer review; a good referee can push for that reframing. I would not cite it for the bound, but I would cite it as a complementary channel in the boosted-neutrino literature.","headline":"Supernova-neutrino boosting is a clean, honestly qualified calculation, but the M*>30 TeV ANITA bound is an upper-limit-driven forecast that does not survive the spectral-index uncertainty in TXS 0506+056.","tokens_in":11895,"tokens_out":3100,"would_cite":false,"duration_ms":34565,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"deepseek-v4-flash","headline":"Cosmic rays scattering off supernova neutrinos can create detectable high-energy neutrinos.","keywords":["boosted supernova neutrinos","cosmic-ray scattering","high-energy neutrino telescopes","TXS 0506+056","ultra-high-energy neutrinos","extra dimensions","active galactic nuclei","neutrino-proton cross section"],"falsifier":"Measure or tightly bound the cosmic-ray proton spectrum of TXS 0506+056 in the $10^{9}$–$10^{11}$ GeV range; if the proton luminosity there is below about $10^{49}$ erg/s or the spectral index is steeper than the $\\alpha = 1.8$–$2.4$ range used, the predicted boosted supernova neutrino flux falls below ANITA's reach and the claimed $M_\\star \\gtrsim 30$ TeV bound does not follow.","tokens_in":10820,"feed_emoji":"🔭","tokens_out":10407,"duration_ms":103860,"temperature":0.7,"pith_summary":"The paper proposes a new production channel for high-energy astrophysical neutrinos: cosmic-ray protons scatter off the around 10 MeV neutrinos released by core-collapse supernovae and boost them to GeV-PeV energies. It argues that in environments with large cosmic-ray and supernova densities, such as some active galactic nuclei, this mechanism can produce a neutrino flux detectable by current or next-generation telescopes using only the Standard Model cross section. Because these collisions can reach $\\sqrt{s} \\sim 10$–$100$ TeV, the same flux is also a probe of new physics that enhances the proton-neutrino cross section, and the absence of ultra-high-energy neutrinos from TXS 0506+056 is used to derive $M_\\star \\gtrsim 30$ TeV for extra-dimensional theories.","feed_headline":"Cosmic rays can boost supernova neutrinos to detectable energies","feed_subtitle":"The same collisions could set the first astrophysical-neutrino bound on extra dimensions, near 30 TeV.","key_machinery":"The load-bearing object is the boosted-supernova-neutrino flux integral of Eq. (3), which folds the source cosmic-ray proton spectrum $d\\Phi_p/dT_p$, the supernova-neutrino density profile $n_{\\mathrm{SN}}(r) = f_{\\mathrm{SN}}(r) R_{\\mathrm{SN}} N_\\nu/(4\\pi r^2 c)$, and the differential neutrino-proton cross section over the galaxy volume up to $T_p^{\\max} = 5\\times 10^{11}$ GeV. The Standard Model cross section is built from the elastic neutral-current formula of Eq. (7) at low energy, deep-inelastic scattering above about 1 GeV, and an $s^{0.363}$ scaling beyond 4 TeV; in extra-dimensional scenarios the same cross section is taken to scale as $s^2$ above a scale $M_\\star$. The mechanism's key feature is that any cross-section enhancement acts both at the production site and at the detector, so new physics enters the observable flux twice.","core_discovery":"The paper computes, from the flux integral of Eq. (3), the high-energy neutrino flux produced when cosmic-ray protons in a galaxy scatter off the supernova neutrino population and kick those neutrinos to much higher energies. For optimistic but individually plausible values of the supernova rate, cosmic-ray luminosity, and distance, the resulting flux approaches current high-energy neutrino telescope sensitivities using only Standard Model neutral-current scattering. For the specific sources with inferred parameter bounds in Table I, the predicted flux lies roughly 4 to 8 orders of magnitude below current experimental sensitivities. The same collisions can reach center-of-mass energies of $\\sqrt{s} \\sim 10$–$100$ TeV, where the proton-neutrino cross section is unmeasured and could grow as $\\sigma \\sim s^2$ in extra-dimensional theories; the non-observation of ultra-high-energy neutrinos from TXS 0506+056 with ANITA is then used to set $M_\\star \\gtrsim 30$ TeV, which the authors describe as the first such limit obtained with astrophysical high-energy neutrino data.","pith_inferences":["The paper leaves implicit that the same mechanism should generate a diffuse cosmic-ray-boosted supernova neutrino background; summing this flux over all star-forming galaxies is a concrete next calculation that would connect to IceCube's diffuse flux.","A direct extension of the $M_\\star$ argument is to recast the projected sensitivities of IceCube-Gen2, GRAND, POEMMA, and TRIDENT with the same cross-section rescaling; if no boosted flux appears, those experiments could push the extra-dimension scale well above 30 TeV.","If the intrinsic ultra-high-energy cosmic-ray luminosity of TXS 0506+056 is hidden by opacity rather than genuinely small, the predicted boosted neutrino flux would be larger than the nominal calculation, turning current upper limits into stricter cross-section tests."],"forward_implications":["Under the benchmark parameters shown in the left panel of Fig. 1, the boosted supernova neutrino flux can reach within reach of existing high-energy neutrino telescopes using only Standard Model neutral-current scattering.","For the specific galaxies and blazar in Table I, the same mechanism predicts fluxes 4 to 8 orders of magnitude below current experimental sensitivity.","The flux depends strongly on the cosmic-ray spectral index; within the $\\alpha = 1.8$–$2.4$ range allowed for TXS 0506+056, the predicted flux varies by orders of magnitude at high energies.","The non-observation of ultra-high-energy neutrinos from TXS 0506+056 by ANITA implies $M_\\star \\gtrsim 30$ TeV for the scale at which an extra-dimensional cross section $\\sigma \\sim s^2$ turns on, a bound comparable to the one from SN1987A and the first claimed from astrophysical high-energy neutrino data."],"supporting_citations":[{"why":"It supplies the earlier boosted cosmic-neutrino-background calculations whose treatment the paper extends to supernova neutrinos.","marker":"[30–33]"},{"why":"It provides the number of neutrinos emitted per supernova used in the target-density estimate.","marker":"[20]"},{"why":"It provides the core-collapse supernova rate range used to set the supernova-neutrino density.","marker":"[36]"},{"why":"It supplies the model parameters used for the blazar TXS 0506+056 in the cosmic-ray flux calculation.","marker":"[58]"},{"why":"It supplies the acceleration radius and the inferred cosmic-ray luminosity for TXS 0506+056 that normalize the predicted flux.","marker":"[50]"},{"why":"It provides the Standard Model neutral-current elastic neutrino-proton cross-section formula used at low energies.","marker":"[59]"},{"why":"It supplies the deep-inelastic scattering cross sections and inelasticities used for center-of-mass energies above about 1 GeV.","marker":"[60, 61]"},{"why":"It provides the high-energy cross-section scaling used to match the deep-inelastic result beyond 4 TeV.","marker":"[62]"},{"why":"It supplies the ultra-high-energy neutrino upper limits from which the extra-dimension scale bound is derived.","marker":"[45]"},{"why":"It supplies the time-dependent IceCube spectral-index range for TXS 0506+056 used to quantify the flux uncertainty.","marker":"[7]"}],"fun_headline_variants":["Cosmic rays kick supernova neutrinos into telescope range","First astrophysical bound on extra dimensions via boosted neutrinos","Supernova neutrinos get a cosmic-ray boost to TeV energies","Cosmic-ray kicked neutrinos could unveil extra dimensions"],"cache_read_input_tokens":3200,"weakest_assumption_plain":"The calculation assumes the cosmic-ray luminosity inferred for TXS 0506+056, about $10^{49}$ erg/s, is carried by an unbroken, proton-dominated power-law spectrum extending to $5\\times10^{11}$ GeV with spectral index $\\alpha$ between 1.8 and 2.4; the source's actual ultra-high-energy cosmic-ray luminosity and spectrum are not directly measured, and a softer spectrum or lower luminosity would reduce the boosted flux and the $M_\\star$ limit by orders of magnitude.","fun_headline_variants_meta":{"raw":{"variants":["Cosmic rays kick supernova neutrinos into telescope range","First astrophysical bound on extra dimensions via boosted neutrinos","Supernova neutrinos get a cosmic-ray boost to TeV energies","Cosmic-ray kicked neutrinos could unveil extra dimensions"]},"model":"deepseek-v4-flash","effort":"low","cost_usd":0.00117,"raw_usage":{"total_tokens":4828,"prompt_tokens":926,"completion_tokens":3902,"prompt_tokens_details":{"cached_tokens":384},"prompt_cache_hit_tokens":384,"prompt_cache_miss_tokens":542,"completion_tokens_details":{"reasoning_tokens":3833}},"tokens_in":542,"tokens_out":3902,"duration_ms":30043,"temperature":1.0,"reasoning_tokens":3833,"cache_read_input_tokens":384,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-08-15T17:27:59.696975+00:00","model_set":{"reader":"deepseek-v4-flash"},"falsifier":"Measure or tightly bound the cosmic-ray proton spectrum of TXS 0506+056 in the $10^{9}$–$10^{11}$ GeV range; if the proton luminosity there is below about $10^{49}$ erg/s or the spectral index is steeper than the $\\alpha = 1.8$–$2.4$ range used, the predicted boosted supernova neutrino flux falls below ANITA's reach and the claimed $M_\\star \\gtrsim 30$ TeV bound does not follow.","supporting_citations":[{"cited_title":"Van Den Bergh, International Astronomical Union Colloquium 145, 1–9 (1996)","cited_arxiv_id":null,"evidence_quote":"It provides the core-collapse supernova rate range used to set the supernova-neutrino density."},{"cited_title":"Constraints on the diffuse high-energy neutrino flux from the third flight of ANITA","cited_arxiv_id":"1803.02719","evidence_quote":"It supplies the ultra-high-energy neutrino upper limits from which the extra-dimension scale bound is derived."}],"review_version":1}