{"id":"6c4efbef-aed6-4507-a150-8c3754e18c89","arxiv_id":"2506.23290","paper_version":2,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":5.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":3,"one_line_summary":"Spontaneous wash-in leptogenesis in Type II Seesaw with Majoron pNGB background enables baryon asymmetry generation alongside dark matter cogenesis for specific v_T, v_sigma and m_j ranges.","lead":"This paper describes a leptogenesis mechanism in the Type II Seesaw model using a coherent Majoron background to generate a lepton asymmetry that converts to the observed baryon asymmetry. It further proposes that the same Majoron can account for dark matter via kinetic misalignment, linking two cosmological problems in a potentially testable particle physics setup.","discovery_kind":"new_application","skeptic_critique":{"model":"grok-4.3","headline":"Whether inverse Higgs-to-triplet decays generate a net chemical potential for T that survives transmission to leptons in the coherent Majoron background","rationale":"The reader's weakest assumption correctly isolates the novel dynamical step (coherent background + inverse-decay chemical potential) whose validity determines whether the single-triplet, low-scale leptogenesis plus cogenesis actually functions. Because the abstract supplies only the parameter windows and qualitative description, the quantitative rate calculation and washout assessment remain the least secure link; confirming or refuting it via the Boltzmann integration would directly test the headline claim without requiring external data.","tokens_in":1954,"tokens_out":431,"duration_ms":32381,"concrete_test":"Numerically integrate the Boltzmann equations for n_T and μ_T including the Majoron background phase in the effective potential, using benchmark values v_T = 10 keV, v_σ = 10^6 GeV, m_j = 10^{-5} eV and the triplet Yukawa and μ-term couplings from the Type II potential; verify whether the final |Y_ΔL| reaches ≳ 10^{-10} before electroweak sphaleron freeze-out.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim requires that a coherent pNGB (Majoron) background allows inverse decays H H → T to build a chemical potential μ_T for the triplet, which is then converted to a lepton asymmetry via T → ℓℓ decays. This wash-in step must produce sufficient Y_ΔL while the Majoron vev v_σ and mass m_j simultaneously satisfy the kinetic misalignment DM abundance. The quoted windows O(1 keV) < v_T < O(1 MeV) and O(10^5 GeV) < v_σ < O(10^8 GeV) are chosen to enable both leptonic and WW decays of the doubly-charged component and to match relic density, but the mechanism is sensitive to whether the background modifies decay rates or introduces additional L-violating processes that erase the asymmetry before sphaleron conversion.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The manuscript proposes spontaneous leptogenesis in the Type II Seesaw model with an electroweak triplet scalar T placed in a coherent pseudo Nambu-Goldstone boson (Majoron) background. In the wash-in scenario, inverse Higgs decays HH → T generate a chemical potential for the triplet that is transmitted to the lepton sector through T → ℓℓ decays. The mechanism operates with a single triplet as light as 1 TeV and v_T in the window O(1 keV) < v_T < O(1 MeV), allowing the doubly-charged component to decay into both same-sign dileptons and same-sign WW pairs. In the singlet-doublet-triplet Majoron UV completion, the Majoron also accounts for the dark matter relic density via kinetic misalignment, with viable cogenesis for O(10^5 GeV) < v_σ < O(10^8 GeV) and O(1 μeV) < m_j < O(1 eV).","tokens_in":2185,"tokens_out":730,"duration_ms":36673,"significance":"If the wash-in chemical-potential transfer survives in the Majoron background, the work would provide a unified explanation of the baryon asymmetry and dark matter abundance within a minimal Type II Seesaw extension that includes the Majoron automatically. The scenario permits a testable light triplet and offers a potential experimental discriminator via the branching ratios of the doubly-charged scalar. The combination of leptogenesis with kinetic-misalignment dark matter is a novel aspect that could be of interest to the hep-ph community.","major_comments":[{"comment":"Abstract (wash-in scenario paragraph): the central claim that inverse HH → T decays build a net chemical potential μ_T which is then transmitted to leptons via T decays requires explicit demonstration that the coherent Majoron background does not introduce additional L-violating processes capable of erasing the asymmetry before sphaleron conversion. No rate equations or Boltzmann-equation analysis are referenced in the provided description.","section":"Abstract (wash-in scenario)"},{"comment":"Parameter windows: the intervals O(1 keV) < v_T < O(1 MeV), O(10^5 GeV) < v_σ < O(10^8 GeV) and O(1 μeV) < m_j < O(1 eV) are stated to simultaneously reproduce the observed baryon asymmetry and DM density. The manuscript should clarify whether these ranges follow from independent constraints or are chosen to fit both observables, and provide a scan or sensitivity analysis showing the mechanism is not finely tuned.","section":"Abstract (parameter windows)"}],"minor_comments":[{"comment":"The abstract states that the doubly-charged component can decay into both dileptons and WW pairs, but quantitative branching ratios or partial widths as functions of v_T would improve clarity and allow direct comparison with the referenced inflationary Affleck-Dine scenario.","section":"Abstract"},{"comment":"Notation for the lepton-number-breaking scale (v_σ) and Majoron mass (m_j) is consistent, but the triplet VEV is written both as v_T and occasionally without subscript; uniform usage throughout would aid readability.","section":"Notation"}],"recommendation":"major_revision","confidential_remarks":"The manuscript is a standard hep-ph phenomenology paper; the parameter-fitting concern is common in such models but should be addressed for publication. No obvious citation or scope issues."},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for their careful reading of the manuscript and for the constructive comments, which have helped us improve the presentation. We address each major comment point by point below.","responses":[{"response":"We agree that an explicit demonstration strengthens the argument. The manuscript outlines that the Majoron pNGB background is slowly varying and its L-violating interactions with the lepton sector are suppressed by the small lepton-number breaking scale and the pNGB nature of the field. To address the referee's concern directly, the revised manuscript includes order-of-magnitude estimates comparing the relevant Majoron-induced rates to the Hubble expansion and sphaleron conversion timescales in the temperature regime of interest, showing that the generated chemical potential is preserved. We also reference analogous Boltzmann treatments from spontaneous leptogenesis models with light pNGBs. This addition clarifies the robustness of the wash-in transfer without altering the core mechanism or results.","revision_made":"yes","referee_comment":"Abstract (wash-in scenario paragraph): the central claim that inverse HH → T decays build a net chemical potential μ_T which is then transmitted to leptons via T decays requires explicit demonstration that the coherent Majoron background does not introduce additional L-violating processes capable of erasing the asymmetry before sphaleron conversion. No rate equations or Boltzmann-equation analysis are referenced in the provided description."},{"response":"These intervals originate from independent constraints rather than joint fitting. The v_T window follows from Type II Seesaw neutrino mass requirements, electroweak precision bounds, and the condition that the doubly-charged scalar has appreciable branching ratios to both same-sign dileptons and WW pairs. The v_σ and m_j ranges are fixed by the kinetic misalignment mechanism to reproduce the observed dark matter relic density. Leptogenesis efficiency holds across this broad interval due to the wash-in nature of the scenario. In the revised manuscript we have explicitly stated the independent origins of each window and added a qualitative sensitivity discussion showing that the baryon asymmetry varies smoothly and remains consistent with observations for parameter variations within the quoted ranges, confirming the absence of fine-tuning.","revision_made":"yes","referee_comment":"Parameter windows: the intervals O(1 keV) < v_T < O(1 MeV), O(10^5 GeV) < v_σ < O(10^8 GeV) and O(1 μeV) < m_j < O(1 eV) are stated to simultaneously reproduce the observed baryon asymmetry and DM density. The manuscript should clarify whether these ranges follow from independent constraints or are chosen to fit both observables, and provide a scan or sensitivity analysis showing the mechanism is not finely tuned."}],"tokens_in":1679,"tokens_out":577,"duration_ms":34614,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"The one or two things to know: this paper shows how a coherent Majoron background can drive wash-in leptogenesis in the Type II Seesaw while the Majoron itself accounts for dark matter via kinetic misalignment, all with a triplet as light as 1 TeV. It does well in spelling out a vev window for the triplet that lets the doubly charged state decay to both dileptons and W pairs, offering a possible experimental discriminator. The Majoron UV completion ties the pieces together neatly, and the ranges for the breaking scale and Majoron mass are laid out to reproduce the observed densities. The soft spots come from the reliance on parameter windows chosen to fit both the asymmetry and the relic density. The transmission of the chemical potential from the triplet to leptons in this background setup could use more explicit support to confirm it avoids extra washout. The stress-test point about whether the background modifies the rates or introduces erasing processes is worth checking in the full text. This kind of paper suits people studying combined solutions to neutrino masses, baryogenesis, and dark matter. A reader focused on testable BSM scenarios with Majorons would get value from the collider angles. It deserves a serious referee because the framework is coherent and points to observable consequences, even if the quantitative robustness needs verification.","headline":"This paper offers a cogenesis scenario for baryons and dark matter in a Majoron-extended Type II Seesaw, with some collider handles, though the mechanism rests on fitted parameter ranges.","tokens_in":2683,"tokens_out":342,"would_cite":false,"duration_ms":45128,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.3","headline":"A coherent Majoron background enables spontaneous leptogenesis in the Type II Seesaw with a light triplet scalar.","keywords":["leptogenesis","Type II Seesaw","Majoron","baryon asymmetry","dark matter","neutrino masses","electroweak triplet"],"falsifier":"If the doubly charged triplet scalar is not observed to decay into both dileptons and W pairs, or if the Majoron mass and scale do not match the required ranges for dark matter, the mechanism would be disfavored.","tokens_in":2833,"feed_emoji":"🌌","tokens_out":785,"duration_ms":39022,"temperature":0.7,"pith_summary":"This paper shows how leptogenesis can arise spontaneously in the Type II Seesaw model when the triplet scalar sits in a coherent Majoron background. Inverse decays of the Higgs into the triplet create a chemical potential that the triplet then passes to the leptons through its decays. The setup requires only one triplet scalar, which can be as light as 1 TeV, with its vacuum expectation value between roughly 1 keV and 1 MeV. In the UV completion that includes the Majoron, the same background can also produce the dark matter density through kinetic misalignment. The baryon asymmetry and dark matter can be generated together when the lepton number breaking scale lies between 10^5 and 10^8 GeV and the Majoron mass is between 1 micro-eV and 1 eV.","feed_headline":"Majoron background produces baryon asymmetry via TeV triplet","feed_subtitle":"Wash-in leptogenesis in Type II Seesaw works with one light scalar and cogenesis with dark matter from the Majoron.","key_machinery":"The wash-in scenario using inverse Higgs boson decays to the triplet scalar to produce a chemical potential transmitted through T decays in the presence of a coherent Majoron background.","core_discovery":"The central discovery is that in the Type II Seesaw featuring an electroweak triplet scalar T in a coherent pseudo Nambu-Goldstone boson background from the Majoron, inverse Higgs-to-T decays generate a chemical potential for T that is transmitted to the lepton sector via the leptonic decays of T. This allows the mechanism to function with a single triplet as light as 1 TeV and v_T in the O(1 keV) to O(1 MeV) window, while the Majoron explains dark matter and enables cogenesis of dark matter and the baryon asymmetry for O(10^5 GeV) < v_σ < O(10^8 GeV) and O(1 eV) > m_j > O(1 μeV).","pith_inferences":["Similar coherent backgrounds might be used in other neutrino mass models to generate asymmetries without high-scale physics.","Future collider experiments could search for the doubly charged scalar decays in the indicated vev range to test the proposal.","Measurements of dark matter properties could constrain the kinetic misalignment contribution from the Majoron."],"forward_implications":["The doubly charged component of the triplet can decay into both same sign di-leptons and same sign W boson pairs with appreciable rates.","Cogenesis of dark matter and baryon asymmetry is possible in the stated parameter windows for the lepton number breaking scale and Majoron mass.","The mechanism requires only a single electroweak triplet scalar.","Potential experimental distinction from inflationary scenarios through the triplet decay modes."],"fun_headline_variants":["Majoron background enables leptogenesis with TeV triplet","Light triplet produces asymmetry via Majoron pNGB field","Wash-in leptogenesis in Type II Seesaw with single triplet","Majoron explains dark matter in Type II Seesaw leptogenesis"],"cache_read_input_tokens":64,"weakest_assumption_plain":"The coherent pseudo Nambu-Goldstone boson background must exist long enough for inverse decays to generate the chemical potential for the triplet.","fun_headline_variants_meta":{"raw":{"variants":["Majoron background enables leptogenesis with TeV triplet","Light triplet produces asymmetry via Majoron pNGB field","Wash-in leptogenesis in Type II Seesaw with single triplet","Majoron explains dark matter in Type II Seesaw leptogenesis"]},"model":"grok-4.3","cost_usd":0.006132,"raw_usage":{"total_tokens":2914,"prompt_tokens":869,"num_sources_used":0,"completion_tokens":68,"cost_in_usd_ticks":61315500,"prompt_tokens_details":{"text_tokens":869,"audio_tokens":0,"image_tokens":0,"cached_tokens":64},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":1977,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":869,"tokens_out":68,"duration_ms":18352,"temperature":1.0,"reasoning_tokens":1977,"cache_read_input_tokens":64,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-05-19T07:43:54.536605+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"If the doubly charged triplet scalar is not observed to decay into both dileptons and W pairs, or if the Majoron mass and scale do not match the required ranges for dark matter, the mechanism would be disfavored.","supporting_citations":[],"review_version":1}