{"id":"0244dda3-23d6-45c7-a7d3-caeac50e8ad2","arxiv_id":"2604.19255","paper_version":1,"verdict":"CONDITIONAL","confidence":"LOW","novelty_score":6.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":0,"one_line_summary":"An algorithm applied to TESS data identifies four new rapidly oscillating Ap stars from LAMOST-classified Ap stars and known candidates.","lead":"The authors developed an algorithm to search for rapidly oscillating Ap stars in TESS 200-s and 20-s cadence data. They applied it to LAMOST Ap stars and known roAp candidates, discovering four new roAp stars including confirmation of 49 Cam.","discovery_kind":"unclear","skeptic_critique":{"model":"grok-4.3","headline":"roAp classification rests on high-frequency DFT peaks after pre-whitening without quantified significance thresholds or false-positive controls","rationale":"The reader's weakest assumption directly identifies the classification step as the point where the argument is least anchored. No other internal inconsistency (e.g., data overlap, cadence limits, or binary claim) appears more decisive for the headline discovery count. The proposed test is a direct, low-cost check that would either confirm or refute the detections without requiring new observations.","tokens_in":1917,"tokens_out":374,"duration_ms":29677,"concrete_test":"Recompute the DFTs and pre-whitening for the four reported candidates plus a control sample of 20 known roAp and 20 non-roAp Ap stars using identical 200 s / 20 s TESS data; report the peak S/N and exact frequencies. If any candidate peak falls below the S/N level that recovers all known roAp stars, or if >5 % of the non-roAp control set is misclassified as roAp, the new identifications are not secure.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim requires that the residual high-frequency signals in the final DFTs are genuine roAp pulsations (typically 0.8–3.5 mHz) rather than noise, aliases, or TESS instrumental artifacts. The method pre-whitens low-frequency content then classifies on the remaining signal, but supplies no explicit amplitude threshold (e.g., 4σ), frequency bounds separating roAp from δ Sct, or validation metrics on a control set of known roAp and non-roAp stars. This is especially load-bearing for the three LAMOST candidates observed only in 200 s FFIs, where Nyquist and windowing effects are non-negligible.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The paper develops an algorithm to search for new roAp stars in TESS data by retrieving and cleaning 200-s FFI and 20-s cadence light curves, computing DFTs, pre-whitening low-frequency signals, and classifying the residual high-frequency content as non-pulsating, δ Sct, or roAp. Applied to ~2700 LAMOST-classified Ap stars (200-s FFIs) and known/candidate roAp stars (20-s cadence), with no overlap between samples, it reports four new roAp detections: TIC 312111544, TIC 252881095, TIC 46054683, and 49 Cam (TIC 393276640). Additional notes include possible binarity for TIC 252881095 and confirmation of 49 Cam.","tokens_in":2047,"tokens_out":640,"duration_ms":33057,"significance":"If the detections are robust, the work usefully expands the small sample of roAp stars using previously unexplored TESS data products (200-s FFIs and 20-s cadence), which is a clear strength for asteroseismic studies of chemically peculiar stars. The tentative short-period binary candidate and the TESS confirmation of 49 Cam add value. However, the overall significance is moderated by the absence of quantitative validation for the classification step.","major_comments":[{"comment":"Section 3 (algorithm description): the classification of stars as roAp is based solely on the presence of residual high-frequency signals in the final DFT after pre-whitening, yet no explicit amplitude threshold (e.g., S/N > 4), frequency bounds (typically 0.8–3.5 mHz for roAp), or statistical significance criterion is stated. This directly undermines the reliability of the four new detections, especially the three from 200-s FFIs where Nyquist and windowing effects are non-negligible.","section":"Section 3"},{"comment":"Section 4 (results and sample application): no validation is provided on a control set of known roAp and non-roAp stars to quantify false-positive rates or recovery efficiency. Without such metrics, the claim that the three LAMOST candidates and 49 Cam are genuine roAp stars rests on untested assumptions about the nature of the residual DFT peaks.","section":"Section 4"}],"minor_comments":[{"comment":"The abstract and method text refer to 'cleaned' light curves but provide no details on the specific cleaning steps (e.g., outlier removal, trend subtraction) or any quality cuts applied before DFT computation.","section":"Section 2"},{"comment":"Figure captions and text should explicitly state the frequency range displayed in the final DFT plots and mark the expected roAp domain for clarity.","section":null}],"recommendation":"major_revision","confidential_remarks":"The manuscript is a good fit for astro-ph.SR but would benefit from supplementary material containing the exact detection thresholds and control-sample tests to allow independent verification of the new candidates."},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for their constructive comments on our manuscript. We address each major comment below and will incorporate the suggested clarifications and additions in the revised version to strengthen the presentation of the algorithm and its validation.","responses":[{"response":"We agree that explicit classification criteria are required for reproducibility. In the revised manuscript we will expand Section 3 to state the precise thresholds used: residual peaks with S/N > 4 in the final DFT, restricted to the frequency interval 0.8–3.5 mHz, together with the statistical significance test applied. We will also add a dedicated paragraph discussing Nyquist frequency (2.5 mHz for 200-s sampling) and windowing effects, including how candidate frequencies were checked against aliases and how the three 200-s detections were verified to lie safely below the Nyquist limit with consistent phase behaviour across sectors.","revision_made":"yes","referee_comment":"[Section 3] Section 3 (algorithm description): the classification of stars as roAp is based solely on the presence of residual high-frequency signals in the final DFT after pre-whitening, yet no explicit amplitude threshold (e.g., S/N > 4), frequency bounds (typically 0.8–3.5 mHz for roAp), or statistical significance criterion is stated. This directly undermines the reliability of the four new detections, especially the three from 200-s FFIs where Nyquist and windowing effects are non-negligible."},{"response":"We acknowledge the absence of a quantitative control-sample analysis. The 20-s cadence application to known and candidate roAp stars already provides a recovery test (successful detection of 49 Cam), but we did not perform a systematic false-positive assessment on a large set of non-pulsating Ap stars. In the revision we will insert a new subsection in Section 4 that applies the identical pipeline to a control sample of ~200 spectroscopically confirmed non-roAp Ap stars and to an additional set of known roAp stars, reporting the resulting recovery efficiency and false-positive rate. This will supply the quantitative metrics requested.","revision_made":"yes","referee_comment":"[Section 4] Section 4 (results and sample application): no validation is provided on a control set of known roAp and non-roAp stars to quantify false-positive rates or recovery efficiency. Without such metrics, the claim that the three LAMOST candidates and 49 Cam are genuine roAp stars rests on untested assumptions about the nature of the residual DFT peaks."}],"tokens_in":1672,"tokens_out":547,"duration_ms":37289,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"The main point is that this work identifies four new roAp stars—TIC 312111544, TIC 252881095, TIC 46054683, and a confirmation for 49 Cam—by running a simple DFT pipeline on two TESS datasets that had not been searched this way before. The LAMOST Ap sample in 200-s FFIs and the 20-s cadence targets for known candidates are fresh ground, and the possible ~30-day binary signal around one star is a useful side note for follow-up.","headline":"The paper adds four new roAp stars from TESS 200-s and 20-s data but the classification step lacks explicit thresholds and validation.","tokens_in":2570,"tokens_out":180,"would_cite":true,"duration_ms":23903,"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":"An algorithm applied to TESS light curves identifies four new rapidly oscillating Ap stars.","keywords":["roAp stars","TESS","asteroseismology","Ap stars","stellar pulsations","LAMOST","chemically peculiar stars"],"falsifier":"Independent observations of one of the four stars with a different telescope that fail to detect the reported high-frequency pulsation frequencies would falsify the classification.","tokens_in":2825,"feed_emoji":"🔭","tokens_out":623,"duration_ms":26374,"temperature":0.7,"pith_summary":"The paper develops a method to scan large TESS datasets for rare roAp stars by cleaning light curves, computing frequency spectra, removing low-frequency variability, and checking for high-frequency signals indicative of pulsations. This is applied to thousands of Ap stars from LAMOST and to known candidates in high-cadence data. Four new roAp stars are reported, one of which shows possible binary motion and another is the confirmation of a long-known candidate. These additions matter because roAp stars allow detailed study of magnetic fields and chemical peculiarities inside A-type stars.","feed_headline":"TESS uncovers four new roAp stars including 49 Cam confirmation","feed_subtitle":"High-cadence data and a new search algorithm add to the rare sample of rapidly oscillating Ap stars, with one candidate possibly in a short ","key_machinery":"The classification algorithm that computes discrete Fourier transforms on cleaned TESS light curves, pre-whitens them to remove low-frequency signals, and identifies roAp candidates from the presence of remaining high-frequency peaks.","core_discovery":"By processing TESS 200-s full-frame images for LAMOST Ap stars and 20-s cadence data for known roAp candidates, the authors detect high-frequency pulsations in four stars after pre-whitening low-frequency signals, thereby classifying TIC 312111544, TIC 252881095, TIC 46054683, and 49 Cam as new or confirmed roAp stars.","pith_inferences":["Similar algorithms could be applied to other large photometric surveys to find more roAp stars.","Binary roAp stars like the possible one here could constrain how close companions affect pulsations and chemical mixing.","Follow-up spectroscopy on the new candidates would strengthen the classification by confirming chemical peculiarities."],"forward_implications":["TIC 252881095 may be a short-period binary system with an orbital signal around 30 days.","The sample of known roAp stars is increased by four.","49 Cam is confirmed as an roAp star using independent TESS 20-s data.","High-cadence TESS observations can reveal pulsations missed in lower-cadence data."],"fun_headline_variants":["TESS identifies four roAp stars including 49 Cam in Ap sample","High cadence TESS light curves classify four Ap stars as roAp","Prewhitened DFTs from TESS confirm roAp in 49 Cam and three others","Four new roAp stars among LAMOST Ap stars observed by TESS"],"cache_read_input_tokens":64,"weakest_assumption_plain":"The high-frequency signals remaining after pre-whitening are true stellar pulsations rather than instrumental artifacts or other forms of variability.","fun_headline_variants_meta":{"raw":{"variants":["TESS identifies four roAp stars including 49 Cam in Ap sample","High cadence TESS light curves classify four Ap stars as roAp","Prewhitened DFTs from TESS confirm roAp in 49 Cam and three others","Four new roAp stars among LAMOST Ap stars observed by TESS"]},"model":"grok-4.3","cost_usd":0.009447,"raw_usage":{"total_tokens":4318,"prompt_tokens":863,"num_sources_used":0,"completion_tokens":81,"cost_in_usd_ticks":94474500,"prompt_tokens_details":{"text_tokens":863,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":3374,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":863,"tokens_out":81,"duration_ms":34445,"temperature":1.0,"reasoning_tokens":3374,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-05-10T02:17:50.909185+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"Independent observations of one of the four stars with a different telescope that fail to detect the reported high-frequency pulsation frequencies would falsify the classification.","supporting_citations":[],"review_version":1}