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**Construction and interpretation of the 200-object tSZ candidate catalog are under-specified and not quantitatively validated against spatially varying noise or external catalogs (Sec.** III.A–C, Sec. IV.A, Sec. XII.C). A single global 5σ threshold is applied to a filtered NILC y-map despite strong noise inhomogeneity (factor ≳3 variation in σ_y, Sec. IV.A). There is no completeness/purity or false-detection assessment, no positional uncertainty estimates, and only a qualitative comparison to the official ACT cluster catalog beyond the Bullet Cluster example (Sec. III.D). This makes the scientific meaning of the 200 “candidates above 5σ” unclear and limits the catalog’s utility. *Recommendation:* In Sec. III–IV, quantitatively characterize the catalog and its selection function. (i) Use the measured local σ_y map (Sec. IV.A) to simulate mock y-maps with realistic spatially varying noise and, if possible, foregrounds, and run the same detection pipeline to estimate completeness and false-positive rates as a function of y and position. (ii) Explicitly state whether ν is defined with a global or local σ_y; if currently global, repeat the detection using a local-threshold definition and compare candidate counts and properties. (iii) Cross-match all 200 candidates with the ACT DR6/DR5 cluster catalog and, where feasible, external optical/X-ray catalogs, reporting match fractions, positional offsets, positional uncertainties, and unmatched objects in a table (Sec. III.C, Sec. XII.C). (iv) Clearly state in Sec. III.C whether the catalog is intended as a cosmological sample or as a high-S/N diagnostic list, and summarize basic completeness/purity metrics.
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**The spectral diagnostics for both the top 20 tSZ candidates and the compact source at (291.2°, −29.2°) rely on single-pixel intensities in non-component-separated maps (Sec.** V.A–B, Sec. VI.A–C). There is no defined aperture, beam correction, or robust error budget (noise, CMB variance, foreground structures), yet the paper draws strong conclusions that only 1–2 of 20 bright candidates are spectrally tSZ-like and that the compact source has a synchrotron-like spectral index α≈−0.4 and a 41σ Compton-y detection. Without proper photometry and uncertainties, these quantitative claims and classifications are not well supported. *Recommendation:* Upgrade the spectral analyses in Sec. V and Sec. VI. (i) Replace or supplement single-pixel values with aperture photometry or matched-filter fluxes at each frequency, using fixed angular or physical apertures, local background subtraction, and beam deconvolution. (ii) Propagate instrumental noise and CMB variance to flux errors and spectral-index uncertainties, for example via simulations or bootstrapping. (iii) Recompute the fraction of tSZ-consistent candidates and the spectral index α and its uncertainty for the compact source, updating Figs. 9–13 and the corresponding text. (iv) If a full upgrade is not feasible, present explicit error budgets and robustness tests (e.g., varying aperture and pixel choice), soften language in Sec. V.B, Sec. VI.C, and Sec. XIII, and clearly label these diagnostics as qualitative rather than quantitative.
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**The non-Gaussianity analysis of the temperature field reports extremely large kurtosis κ≈47 and a formal significance quoted as ">100σ" relative to Gaussian simulations (Sec.** VII.A). However, the simulation setup is only briefly described (≈100 Gaussian noise realizations with matched variance), with unclear treatment of CMB signal, beams, anisotropic noise, and unresolved sources. The test statistic distribution is not characterized beyond a simple σ estimate, and there is limited exploration of how much κ is driven by bright sources versus a diffuse population. This combination of sparse methodology and very large quoted significance undermines the credibility and interpretability of the result. *Recommendation:* Substantially clarify and temper the non-Gaussianity analysis in Sec. VII.A. (i) Provide a detailed description of the simulations: specify whether they include CMB, beam smoothing, anisotropic noise, and realistic foreground populations, and increase the number of realizations (preferably ≥1000) to robustly estimate the distribution of κ. (ii) Avoid using ">100σ"; instead, report empirical p-values or a lower bound on the significance if κ lies beyond the simulated range. (iii) Quantitatively dissect the signal by recomputing κ after masking bright sources at several thresholds and comparing to simulations with point-source and SZ populations consistent with ACT DR6. (iv) Explicitly state the sky area, mask, and effective multipole range of the 2000×2000-pixel patch. Use these diagnostics to refine the physical interpretation (unresolved extragalactic sources vs. potential systematics) and update the summary in Sec. XIII accordingly.
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**Several high-significance quantitative claims—such as the 41σ Compton-y detection of the compact source (Sec.** VI.A), the extreme κ significance (Sec. VII.A), and the very tight birefringence limit |β|<0.01° with vanishing TB/EB (Sec. X.B–C)—are presented with minimal methodological detail about noise modeling, covariance estimation, and systematics. For example, it is unclear how the y significance at the compact source incorporates local noise inhomogeneity or beam smoothing, and the birefringence analysis lacks discussion of estimators, foregrounds, and instrumental uncertainties. This mismatch between strong numerical claims and sparse methodology makes it difficult to gauge robustness. *Recommendation:* For each major high-significance result, add concise but complete methodological descriptions. (i) In Sec. VI.A, specify how the Compton-y significance is defined (global vs. local σ_y, role of filtering, use of split-map cross-estimators) and how anisotropic noise is accounted for. (ii) In Sec. VII.A, clearly describe how uncertainties in κ are derived from simulations (as per the previous issue). (iii) In Sec. X.B–C, state the birefringence and isocurvature estimators used (e.g., TB/EB quadratic estimators), how covariance matrices are obtained (analytic vs. simulations), and which systematics (beam mismatch, calibration, E/B leakage, foregrounds) are included. Where systematics are not incorporated, explicitly label the quoted limits as statistical only and compare them with existing Planck/ACT constraints to set expectations.
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**The cross-frequency correlation analysis that identifies four cells with anomalously low 90×150 GHz pixel-space correlation (ρ<0.12) and a median ρ≈0.69 (Sec.** VII.C) is only briefly described, with key methodological choices (masking, resolution/smoothing, pixel selection, noise debiasing, CMB vs. foreground separation) left implicit. Without simulations or error estimates, it is unclear whether these low-ρ regions are statistically significant anomalies or expected fluctuations due to foregrounds and noise, which weakens their interpretation as prioritized follow-up targets (Sec. VII.C, Sec. XII.A). *Recommendation:* Expand Sec. VII.C to fully specify the correlation calculation: (i) state the map resolution and any smoothing applied, the masks used (e.g., NILC footprint, point-source/Galactic masks), and how means are removed within each cell; (ii) indicate whether pixels are inverse-variance weighted and whether any noise debiasing is applied; and (iii) define the grid (RA/Dec bin edges, cell size) and clarify that quoted coordinates are cell centers. Then, use simulations (CMB+noise+foreground templates, with ACT-like coverage) to estimate the expected distribution of ρ per cell, quantify p-values for the four ρ<0.12 regions, and, if possible, test correlations separately in low-ℓ vs. high-ℓ filtered maps. Update Sec. VII.C and Sec. XII.A to distinguish between statistically significant anomalies and features consistent with expected fluctuations.
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**The compact source at (291.2°, −29.2°), highlighted as a key discovery and follow-up target (Sec.** VI, Sec. XII.A, Sec. XIII), is only minimally characterized. The derivation of its synchrotron-like spectral index α≈−0.4 lacks detailed documentation (uncertainties, bandpass corrections, use of all three bands), and there is no reported cross-match with existing radio or cluster catalogs. Without robust SED fitting and positional cross-identification, it is hard to assess whether this is a known radio source coincident with a cluster, a mis-characterized foreground fluctuation, or a genuinely new system. *Recommendation:* In Sec. VI, add a more complete characterization of the compact source. (i) Perform a quantitative SED fit using aperture/matched-filter photometry in all three ACT bands, including error bars and proper treatment of effective bandpasses when inferring α; provide a small table of fluxes/temperatures and uncertainties. (ii) Use the local σ_y map to compute a more realistic y significance at this position, consistent with the definitions in Sec. III–IV. (iii) Systematically cross-match the source position with public radio and cluster catalogs (e.g., NVSS, SUMSS, optical/X-ray cluster catalogs, ACT SZ catalogs) within a few-arcminute radius, and report any matches or upper limits. Discuss in Sec. VI.C and Sec. XII.A how these results affect its interpretation as a synchrotron source, cluster, or composite system.
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**Coordinate and catalog inconsistencies, especially in the radial-profile outlier table and some follow-up target descriptions, compromise reproducibility and can confuse readers.** In particular, Table III (Sec. VIII) lists declinations like +166.3 and +173.8, which are unphysical for equatorial coordinates, and coordinates for low-ρ regions (Sec. VII.C) are given without clear definition of whether they correspond to cell centers or boundaries. There are also inconsistencies in Bullet Cluster significance and candidate numbering between Sec. III.C, Sec. IV.D, Sec. XII.A, and Tables II–III (e.g., 49σ vs. 51.2σ for the Bullet, ambiguous association with “candidate 1” or “candidate 2”). *Recommendation:* Systematically audit and correct all coordinates and catalog references. (i) In Sec. VIII and Table III, verify declinations fall within −90° to +90°; if current values are typos or placeholders, replace them with correct equatorial coordinates or clearly state an alternative coordinate system and relabel columns. (ii) In Sec. VII.C and the corresponding figure, define the 12×8 RA/Dec grid, giving bin edges and specifying whether quoted positions are cell centers; provide a small table (in the main text or an appendix) listing the four low-ρ regions with explicit RA/Dec ranges. (iii) Clarify in Sec. III.C, Sec. IV.D, Sec. XII.A, and associated tables which catalog entry corresponds to the Bullet Cluster, and ensure its ν-significance (e.g., ~49σ) and candidate number are consistently quoted. Check RA/Dec and significance for the compact source and all high-profile candidates. Correct any discrepancies in the final manuscript so that readers can reliably cross-identify all reported objects.
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**Several figures (e.g., Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 7, Figure 8, Figure 10, Figure 11, Figure 12, Figure 13, Figure 14, Figure 17, Figure 18) exhibit missing or incomplete panels, ambiguous or inconsistent labeling (axes, units, or panel references), lack of uncertainty quantification, and insufficient methodological detail (e.g., sample definitions, processing steps, or normalization).** These issues collectively hinder reproducibility, interpretation, and the ability to assess the statistical significance or physical meaning of the results. *Recommendation:* For all affected figures, ensure that all referenced panels are present and clearly labeled; provide explicit axis units, colorbar labels, and panel annotations; add uncertainty estimates (error bars, confidence bands, or statistical summaries) where relevant; and update captions to specify sample definitions, processing steps, and normalization or masking procedures. Where applicable, reconcile figure content with text descriptions and catalog numbers, and clarify any selection or filtering criteria.
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**Color scaling, masking, and normalization are inconsistent or ambiguous in several figures (notably Figures 5, 7, 8, 10, 11, 12, 14, 17, 18), leading to potential misinterpretation of dynamic range, signal significance, or spatial coverage.** In some cases, no-data regions are indistinguishable from low-signal areas, and color choices may not be accessible to all readers. *Recommendation:* Adopt consistent, zero-centered, and clearly annotated color scales across related panels; explicitly mask or distinguish no-data regions; use colorblind-safe, perceptually uniform palettes; and provide shared colorbars where possible. Annotate or overlay survey boundaries, noise/depth contours, and beam/PSF information to clarify spatial coverage and resolution. Ensure that all colorbar units and scaling conventions are documented in captions.
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**Non-Gaussianity verification is internally inconsistent: the paper reports a very large excess kurtosis for the f150 coadded map (κ ≈ 47) but then states split-map verification yields κ ≈ 1.66 per split (Sec.** VII.A, p.6–7). These values differ by ~O(10–30×) without any analytic explanation (e.g., different estimator, masking, filtering, window size, or normalization). *Recommendation:* Explicitly state whether κ is computed on the same pixels/patches, with the same preprocessing (mean subtraction, masking, smoothing, apodization) and the same estimator for coadds vs splits. If different, provide the exact estimator definitions for each and explain why κ should change by that amount; otherwise correct the reported κ values.
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**Positive-tail Compton-y extent (y ≈ 5.5×10−4) is ~12.0× larger than the maximum y reported for the highest-significance Table II candidate (y = 4.57×10−5), raising a potential definition/unit mismatch or a mismatch between what Table II summarizes versus what the tail describes.** *Recommendation:* Clarify whether the Section IV.B 'positive tail' y uses the same map, smoothing, units, and statistic as the Table II y values; if they differ, explicitly state the definition and scaling for each and reconcile why the global tail maximum does not appear in the top-significance list.
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**Inconsistent trials factor used for multiple-testing correction: one section states eleven parallel analyses (divide by 11), while another states twelve parallel analyses (multiply p-value by 12).** *Recommendation:* Standardize the effective trials factor throughout (choose 11 or 12) and update all Bonferroni/p-value corrections accordingly; if the number changed due to inclusion/exclusion of an analysis, describe that decision and ensure all corrected significances reflect the final count.