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Wide parameter-space O3 search for continuous gravitational waves from unknown neutron stars in binary systems

T0 review · 1 major / 0 minor · reviewed 2026-06-30 · grok-4.3

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Pith's one-line read No continuous gravitational wave signals from unknown binary neutron stars detected in O3 data, setting new upper limits on amplitudes.

desk verdict This O3 search extends continuous-wave binary coverage to frequencies above 520 Hz and orbital periods under 3 days for the first time with advanced detectors, producing new upper limits on ellipticities and r-modes, though the exclusions depend on unshown pipeline completeness in those regimes. read the letter →

arxiv 2605.14728 v1 pith:C7TBAQX5 submitted 2026-05-14 gr-qc astro-ph.HE

P. B. Covas , M. A. Papa , R. Prix This is my paper · ORCID
classification gr-qcastro-ph.HE
keywords continuousgravitationalwavesneutronstarsbinarysystemsLIGOO3upperlimitsellipticityr-modeswavesearches
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper reports on a comprehensive search for continuous gravitational waves from unknown neutron stars in binary systems using LIGO O3 data. It covers a wide range of gravitational-wave frequencies from 50 to 1000 Hz and orbital periods shorter than 3 days for the first time with advanced detectors. No signals are found, allowing the authors to place the most stringent constraints to date on the possible amplitudes of such signals. These results are important because binary systems are common among fast-spinning pulsars, and accretion in binaries can create the asymmetry needed for gravitational wave emission. A sympathetic reader would care because it narrows down the properties neutron stars must have if they are to produce detectable continuous waves.

What carries the argument

The matched-filtering search over a large template bank covering frequency, frequency derivative, and binary orbital parameters.

What would settle it

A confirmed detection of a continuous gravitational wave from a neutron star in a binary system within 100 pc, with rotation frequency above 495 Hz and ellipticity exceeding 5.2×10^{-8}, would contradict the exclusion limits.

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Extended reading notes

Core claim

The search of the O3 dataset finds no evidence for continuous gravitational waves from unknown neutron stars in binary systems. It excludes with 95% confidence that neutron stars within 100 pc rotating faster than approximately 495 Hz have ellipticities above 5.2 × 10^{-8}. Similarly, it excludes r-mode amplitudes above 1.5 × 10^{-6} for stars rotating faster than approximately 740 Hz within the same distance.

Load-bearing premise

The template bank and analysis pipeline are complete enough to detect any signal above the reported amplitude thresholds without significant losses from approximations or data quality issues.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

1 major / 0 minor

Summary. The manuscript reports results from a wide parameter-space search for continuous gravitational waves from unknown neutron stars in binary systems using LIGO O3 data. It covers gravitational-wave frequencies from 50 to 1000 Hz and, for the first time with advanced detectors, orbital periods shorter than 3 days. No signals are detected. The authors set the most stringent constraints to date, excluding with 95% confidence neutron stars within 100 pc rotating faster than ~495 Hz from having ellipticities above 5.2×10^{-8}, and excluding r-mode amplitudes above 1.5×10^{-6} for stars rotating faster than ~740 Hz.

Significance. If the search completeness and sensitivity are validated, the work provides the tightest limits to date on continuous-wave signals from binary neutron stars by extending coverage into previously unexplored high-frequency and short-orbital-period regimes. This is valuable for constraining neutron-star asymmetries and accretion mechanisms. The computational scope of the search is a notable strength.

major comments (1)
  1. [Results and Methods sections (validation of template bank and sensitivity)] The 95% confidence exclusion limits on ellipticity and r-mode amplitude (stated in the abstract and results) rest on the assumption that the template bank and pipeline are complete and sensitive across the full 50-1000 Hz range and all orbital periods down to <3 days with low mismatch. The manuscript must include explicit validation (e.g., mismatch calculations or recovery fractions from injections) specifically for the newly explored regimes above 520 Hz and below 3-day periods; without this, the robustness of the quoted thresholds cannot be verified and the central claim is not fully supported.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their careful reading of the manuscript and for highlighting the need for explicit validation in the newly explored parameter space. We address the comment below.

read point-by-point responses

  1. Referee: [Results and Methods sections (validation of template bank and sensitivity)] The 95% confidence exclusion limits on ellipticity and r-mode amplitude (stated in the abstract and results) rest on the assumption that the template bank and pipeline are complete and sensitive across the full 50-1000 Hz range and all orbital periods down to <3 days with low mismatch. The manuscript must include explicit validation (e.g., mismatch calculations or recovery fractions from injections) specifically for the newly explored regimes above 520 Hz and below 3-day periods; without this, the robustness of the quoted thresholds cannot be verified and the central claim is not fully supported.

    Authors: We agree that explicit validation for the high-frequency and short-orbital-period regimes is essential to support the quoted limits. Although the Methods section describes the general construction of the template bank with mismatch bounds and the sensitivity estimation procedure, we acknowledge that specific demonstrations for the new regimes (f > 520 Hz and P_orb < 3 days) were not included. In the revised version, we will add a dedicated paragraph or subsection presenting mismatch histograms and injection recovery fractions for representative points in these regimes, confirming that the pipeline performs as designed. revision: yes

Circularity Check

0 steps flagged · score 0.0 of 10

Observational matched-filter search yields data-driven upper limits with no circular derivation.

full rationale

This is a standard gravitational-wave search paper that applies matched filtering to real LIGO O3 detector data over an expanded parameter space (50-1000 Hz, orbital periods <3 days). The central results—no detected signals and 95% confidence exclusion limits on ellipticity (5.2e-8) and r-mode amplitude (1.5e-6) for d<100 pc—are extracted empirically from the lack of candidates above threshold. No equations, predictions, or uniqueness claims reduce by construction to fitted inputs, self-citations, or ansatzes; the pipeline completeness assumption is an external methodological claim, not a self-referential loop. The derivation chain is self-contained against external data.

Assumptions & free parameters 0 free parameters · 2 assumptions · 0 invented entities

Review based on abstract only; the work rests on standard domain assumptions of gravitational-wave astronomy rather than new postulates.

assumptions (2)
  • domain assumption LIGO O3 strain data can be searched for continuous-wave signals via matched filtering after standard noise subtraction and vetoes.
    Standard assumption invoked whenever a continuous-wave search reports upper limits from real detector data.
  • domain assumption Neutron stars in binaries can sustain the ellipticities or r-modes needed to produce detectable continuous gravitational waves.
    Background assumption from general relativity and neutron-star astrophysics used to interpret non-detections as constraints on those quantities.

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Cite this review

Pith. "Pith review of Wide parameter-space O3 search for continuous gravitational waves from unknown neutron stars in binary systems." pith.science (2026). https://pith.science/paper/C7TBAQX5

@misc{pith2026260514728,
  author       = {Pith},
  title        = {Pith review of: Wide parameter-space O3 search for continuous gravitational waves from unknown neutron stars in binary systems},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/C7TBAQX5}},
  note         = {Machine review of arXiv:2605.14728}
}
abstract

Continuous gravitational waves, i.e., persistent and nearly-monochromatic signals emitted by asymmetric spinning neutron stars, remain elusive. Searches for these signals from unknown binary systems are the most computationally challenging, but they are essential, given that binary accretion provides a natural mechanism for creating the required asymmetry, and around half of the known pulsars rotating above 25 Hz are part of a binary system. Here we report on a search of a large uncharted parameter-space region: for the first time we cover gravitational-wave frequencies above 520 Hz (from 50 to 1000 Hz), and, for the first time with advanced detectors, orbital periods lower than 3 days are explored. No signal is detected, and we set the most stringent constraints to date on the amplitude of signals of this kind. Our results exclude with $95\%$ confidence neutron stars within 100 pc and rotating faster than $\sim$ 495 Hz from having ellipticities above $5.2 \times 10^{-8}$. Within the same distance our results also exclude r-mode amplitudes above $1.5 \times 10^{-6}$ for stars rotating faster than $\sim$ 740 Hz.

Figures

Figures reproduced from arXiv: 2605.14728 by the authors.

Figure 1
Figure 1. The black boxes show the signal-parameter regions covered by this search (left plot shows {Porb, ap}, right plot shows {Porb, ν0}). The circles show the known pulsars in binary systems from the ATNF catalog version 2.6.3 (Manchester et al. 2005) and the color encodes ν0 (left plot) and ap (right plot). The dashed boxes show the ranges covered by previous searches using O3 or O4 Advanced LIGO data. The different gray… view at source ↗
Figure 2
Figure 2. Square root of the harmonic mean power spectral density √ Sn of the data used in this search as a function of frequency. The upper blue curve shows H1, the middle green curve shows H1+L1, and the lower orange curve shows L1. (Manchester et al. 2005) have eccentricities outside of the range defined by equations (2) and (3). 2.3. Initial search We use the BinarySkyHouF (Covas & Prix 2022a) semi-coherent search method … view at source ↗
Figure 3
Figure 3. Maximum significance s0 of the initial stage in each 0.1 Hz frequency band as a function of the gravitation￾al-wave frequency. The black lines show the threshold to consider a band non-Gaussian. A few bands with negative maximum s0 values are not shown on the plot. ceptance/rejection regions in the s0 − s1 and s0 − log10 Bˆ 1;S/GLtL planes for the candidates. Our criteria has a false dismissal probability of about 1… view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: Distribution of significance values s1 (left plot) and log10 Bˆ 1;S/GLtL (right plot) for the follow-up. In the right plot we use a “symlog” scale, i.e., linear between -1 and 1. The blue circles show the 7 200 simulated test-signals, and the crosses indicate the 127 5…
Figure 5
Figure 5. Figure 5: Estimated upper limits on the gravitational-wave amplitude h 95% 0 (left plot), on the neutron star ellipticity ϵ (upper right plot), and on the r-mode amplitude α (lower right plot) at the 95% confidence level as a function of the gravitational-wave frequency. Left pl…
Figure 6
Figure 6. Figure 6: Mismatch distribution of this search at two differ￾ent frequencies, in the 200 Hz and 800 Hz region, respectively. The other parameters that describe the CW signal span the ranges given in table 1. The legend shows the mean of each distribution for each different regio…
Figure 8
Figure 8. Figure 8: Illustrative example of the detection probability as a function of the normalized inverse signal-amplitude (D) for signals at ≈ 803.4 Hz and with orbital parameters from region A. The top axis shows the corresponding values of the signal amplitude (h0). The error bars …

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Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. First Constraints on the Ellipticities of Self-Interacting Fermionic Dark Matter Admixed Neutron Stars from Continuous Gravitational-Wave Searches

    astro-ph.CO 2026-06 unverdicted novelty 7.0 of 10

    Using LIGO O3 continuous-wave search data, the authors place the first constraints on ellipticities of self-interacting fermionic dark matter admixed neutron stars and exclude regions of the DM parameter space for mas...

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Works this paper leans on

43 extracted references · 43 canonical work pages · cited by 1 Pith paper

  1. [1]

    P., Abbott, R., et al

    Aasi, J., Abbott, B. P., Abbott, R., et al. 2014, Phys. Rev. D, 90, 062010, doi: 10.1103/PhysRevD.90.062010

    work page doi:10.1103/physrevd.90.062010 2014

  2. [2]

    G., Abouelfettouh, I., Acernese, F., et al

    Abac, A. G., Abouelfettouh, I., Acernese, F., et al. 2025, arXiv, 2511.16863, doi: 10.48550/arXiv.2511.16863

    work page doi:10.48550/arxiv.2511.16863 2025

  3. [3]

    2007, Phys

    Abbott, B., Abbott, R., Adhikari, R., et al. 2007, Phys. Rev. D, 76, 042001, doi: 10.1103/PhysRevD.76.042001

    work page doi:10.1103/physrevd.76.042001 2007

  4. [4]

    D., Abraham, S., et al

    Abbott, R., Abbott, T. D., Abraham, S., et al. 2021, Phys. Rev. D, 103, 064017, doi: 10.1103/PhysRevD.103.064017

    work page doi:10.1103/physrevd.103.064017 2021

  5. [5]

    2022, Phys

    Abbott, R., Abe, H., Acernese, F., et al. 2022, Phys. Rev. D, 106, 102008, doi: 10.1103/PhysRevD.106.102008 —. 2023, Astrophys. J. Supplement Series, 267, 29, doi: 10.3847/1538-4365/acdc9f

    work page doi:10.1103/physrevd.106.102008 2022

  6. [6]

    2004, Tech

    Allen, B., & Mendell, G. 2004, Tech. Rep. T040164. https://dcc.ligo.org/LIGO-T040164/public

    work page 2004

  7. [7]

    I., & Prix, R

    Ashton, G., Jones, D. I., & Prix, R. 2015, Phys. Rev. D, 91, 062009, doi: 10.1103/PhysRevD.91.062009

    work page doi:10.1103/physrevd.91.062009 2015

  8. [8]

    Ashton, G., Prix, R., & Jones, D. I. 2017, Phys. Rev. D, 96, 063004, doi: 10.1103/PhysRevD.96.063004

    work page doi:10.1103/physrevd.96.063004 2017

Show all 43 references
  1. [9]

    D., et al

    Ashton, G., H¨ ubner, M., Lasky, P. D., et al. 2019, Astrophys. J. Supplement Series, 241, 27, doi: 10.3847/1538-4365/ab06fc

    2019 doi

  2. [10]

    A., & Prix, R

    Behnke, B., Papa, M. A., & Prix, R. 2015, Phys. Rev. D, 91, 064007, doi: 10.1103/PhysRevD.91.064007

    2015 doi

  3. [11]

    C., et al

    Biwer, C., Barker, D., Batch, J. C., et al. 2017, Phys. Rev. D, 95, 062002, doi: 10.1103/PhysRevD.95.062002

    2017 doi

  4. [12]

    1996, A&A, 312, 675, doi: 10.48550/arXiv.astro-ph/9602107

    Bonazzola, S., & Gourgoulhon, E. 1996, A&A, 312, 675, doi: 10.48550/arXiv.astro-ph/9602107

    1996 doi arXiv

  5. [13]

    A., & Wasserman, I

    Bondarescu, R., Teukolsky, S. A., & Wasserman, I. 2007, Phys. Rev. D, 76, 064019, doi: 10.1103/PhysRevD.76.064019

    2007 doi

  6. [14]

    L., et al

    Buikema, A., Cahillane, C., Mansell, G. L., et al. 2020, Phys. Rev. D, 102, 062003, doi: 10.1103/PhysRevD.102.062003

    2020 doi

  7. [15]

    I., Gusakov, M

    Chugunov, A. I., Gusakov, M. E., & Kantor, E. M. 2014, MNRAS, 445, 385, doi: 10.1093/mnras/stu1772

    2014 doi

  8. [16]

    B., Papa, M

    Covas, P. B., Papa, M. A., & Prix, R. 2025, Astrophys. J., 985, 192, doi: 10.3847/1538-4357/adcc2b —. 2026, https: //www.aei.mpg.de/continuouswaves/O3AllSkyBinary2

    2025 doi

  9. [17]

    B., Papa, M

    Covas, P. B., Papa, M. A., Prix, R., & Owen, B. J. 2022, Astrophys. J. Lett., 929, L19, doi: 10.3847/2041-8213/ac62d7

    2022 doi

  10. [18]

    B., & Prix, R

    Covas, P. B., & Prix, R. 2022a, Phys. Rev. D, 106, 084035, doi: 10.1103/PhysRevD.106.084035 —. 2022b, Phys. Rev. D, 105, 124007, doi: 10.1103/PhysRevD.105.124007 10

    doi

  11. [19]

    B., Prix, R., & Martins, J

    Covas, P. B., Prix, R., & Martins, J. 2024, Phys. Rev. D, 110, 024053, doi: 10.1103/PhysRevD.110.024053

    2024 doi

  12. [20]

    B., & Sintes, A

    Covas, P. B., & Sintes, A. 2020, Phys. Rev. Lett., 124, 191102, doi: 10.1103/PhysRevLett.124.191102

    2020 doi

  13. [21]

    B., & Sintes, A

    Covas, P. B., & Sintes, A. M. 2019, Phys. Rev. D, 99, 124019, doi: 10.1103/PhysRevD.99.124019

    2019 doi

  14. [22]

    B., Effler, A., Goetz, E., et al

    Covas, P. B., Effler, A., Goetz, E., et al. 2018, Phys. Rev. D, 97, 082002, doi: 10.1103/PhysRevD.97.082002

    2018 doi

  15. [23]

    2018, Phys

    Dreissigacker, C., Prix, R., & Wette, K. 2018, Phys. Rev. D, 98, 084058, doi: 10.1103/PhysRevD.98.084058

    2018 doi

  16. [24]

    F., Zdunik, J

    Fantina, A. F., Zdunik, J. L., Chamel, N., et al. 2022, A&A, 665, A74, doi: 10.1051/0004-6361/202243715

    2022 doi

  17. [25]

    2019, MNRAS, 488, 99–110, doi: 10.1093/mnras/stz1719 —

    Gittins, F., & Andersson, N. 2019, MNRAS, 488, 99–110, doi: 10.1093/mnras/stz1719 —. 2021, MNRAS, 507, 116, doi: 10.1093/mnras/stab2048

    2019 doi

  18. [26]

    E., Chugunov, A

    Gusakov, M. E., Chugunov, A. I., & Kantor, E. M. 2014a, Phys. Rev. Lett., 112, 151101, doi: 10.1103/PhysRevLett.112.151101 —. 2014b, Phys. Rev. D, 90, 063001, doi: 10.1103/PhysRevD.90.063001

    doi

  19. [27]

    Horowitz, C. J. 2010, Phys. Rev. D, 81, 103001, doi: 10.1103/PhysRevD.81.103001

    2010 doi

  20. [28]

    J., & Jones, D

    Hutchins, T. J., & Jones, D. I. 2023, MNRAS, 522, 226, doi: 10.1093/mnras/stad967

    2023 doi

  21. [29]

    Jaranowski, P., Kr´ olak, A., & Schutz, B. F. 1998, Phys. Rev. D, 58, 063001, doi: 10.1103/PhysRevD.58.063001

    1998 doi

  22. [30]

    I., & Riles, K

    Jones, D. I., & Riles, K. 2025, Class. Quant. Grav., 42, 033001, doi: 10.1088/1361-6382/ada244

    2025 doi

  23. [31]

    2016, Phys

    Keitel, D. 2016, Phys. Rev. D, 93, 084024, doi: 10.1103/PhysRevD.93.084024

    2016 doi

  24. [32]

    2015, Phys

    Leaci, P., & Prix, R. 2015, Phys. Rev. D, 91, 102003, doi: 10.1103/PhysRevD.91.102003

    2015 doi

  25. [33]

    N., Hobbs, G

    Manchester, R. N., Hobbs, G. B., Teoh, A., & Hobbs, M. 2005, Astronom. J., 129, 1993–2006, doi: 10.1086/428488

    2005 doi

  26. [34]

    2018, Phys

    Mukherjee, A., Messenger, C., & Riles, K. 2018, Phys. Rev. D, 97, 043016, doi: 10.1103/PhysRevD.97.043016

    2018 doi

  27. [35]

    Owen, B. J. 2005, Phys. Rev. Lett., 95, 211101, doi: 10.1103/PhysRevLett.95.211101 —. 2010, Phys. Rev. D, 82, 104002, doi: 10.1103/PhysRevD.82.104002

    2005 doi

  28. [36]

    Patruno, A., & Watts, A. L. 2020, Accreting Millisecond X-ray Pulsars (Springer Berlin Heidelberg), 143–208, doi: 10.1007/978-3-662-62110-3 4

    2020 doi

  29. [37]

    2023, Liv

    Riles, K. 2023, Liv. Rev. in Relat., 26, 1, doi: 10.1007/s41114-023-00044-3

    2023 doi

  30. [38]

    Rossetto, P. H. B., Frauendiener, J., & Melatos, A. 2025, Astrophys. J., 979, 10, doi: 10.3847/1538-4357/ada276

    2025 doi

  31. [39]

    2020, MNRAS, 493, 3866, doi: 10.1093/mnras/staa442

    Singh, N., Haskell, B., Mukherjee, D., & Bulik, T. 2020, MNRAS, 493, 3866, doi: 10.1093/mnras/staa442

    2020 doi

  32. [40]

    2022, Phys

    Steltner, B., Papa, M., & Eggenstein, H. 2022, Phys. Rev. D, 105, 022005, doi: 10.1103/PhysRevD.105.022005

    2022 doi

  33. [41]

    A., Eggenstein, H.-B., et al

    Steltner, B., Papa, M. A., Eggenstein, H.-B., et al. 2021, Astrophys. J., 909, 79, doi: 10.3847/1538-4357/abc7c9

    2021 doi

  34. [42]

    Tenorio, R., Keitel, D., & Sintes, A. M. 2021, Universe, 7, 474, doi: 10.3390/universe7120474

    2021 doi

  35. [43]

    2023, Astroparticle Physics, 153, 102880, doi: 10.1016/j.astropartphys.2023.102880

    Wette, K. 2023, Astroparticle Physics, 153, 102880, doi: 10.1016/j.astropartphys.2023.102880

    2023 doi

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