Papers
Topics
Authors
Recent
Gemini 2.5 Flash
Gemini 2.5 Flash
173 tokens/sec
GPT-4o
7 tokens/sec
Gemini 2.5 Pro Pro
46 tokens/sec
o3 Pro
4 tokens/sec
GPT-4.1 Pro
38 tokens/sec
DeepSeek R1 via Azure Pro
28 tokens/sec
2000 character limit reached

Unbiased estimation of gravitational-wave anisotropies from noisy data (2312.09110v2)

Published 14 Dec 2023 in astro-ph.CO and gr-qc

Abstract: One of the most exciting targets of current and future gravitational-wave observations is the angular power spectrum of the astrophysical GW background. This cumulative signal encodes information about the large-scale structure of the Universe, as well as the formation and evolution of compact binaries throughout cosmic time. However, the finite rate of compact binary mergers gives rise to temporal shot noise, which introduces a significant bias in measurements of the angular power spectrum if not explicitly accounted for. Previous work showed that this bias can be removed by cross-correlating GW sky maps constructed from different observing times. However, this work considered an idealised measurement scenario, ignoring detector specifics and in particular noise contributions. Here we extend this temporal cross-correlation method to account for these difficulties, allowing us to implement the first unbiased anisotropic search pipeline for LIGO-Virgo-KAGRA data. In doing so, we show that the existing pipeline is biased even in the absence of shot noise, due to previously neglected sub-leading contributions to the noise covariance. We apply our pipeline to mock LIGO data, and find that our improved analysis will be crucial for stochastic searches from the current observing run (O4) onwards.

Definition Search Book Streamline Icon: https://streamlinehq.com
References (27)
  1. LIGO Scientific Collaboration and Virgo Collaboration, GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs, Phys. Rev. X 9, 031040 (2019).
  2. LIGO Scientific Collaboration and Virgo Collaboration, GWTC-2: Compact Binary Coalescences Observed by LIGO and Virgo during the First Half of the Third Observing Run, Phys. Rev. X 11, 021053 (2021).
  3. LIGO Scientific Collaboration and Virgo Collaboration and KAGRA Collaboration, GWTC-3: Compact Binary Coalescences Observed by LIGO and Virgo During the Second Part of the Third Observing Run, arXiv e-prints , arXiv:2111.03606 (2021a), arXiv:2111.03606 [gr-qc] .
  4. LIGO Scientific Collaboration and Virgo Collaboration and KAGRA Collaboration, Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA, Living Rev. Rel. 21, 3 (2018), arXiv:1304.0670 [gr-qc] .
  5. B. Allen, The Stochastic Gravity-Wave Background: Sources and Detection, in Relativistic Gravitation and Gravitational Radiation, edited by J.-A. Marck and J.-P. Lasota (1997) pp. 373–417, arXiv:gr-qc/9604033 [gr-qc] .
  6. N. Christensen, Stochastic gravitational wave backgrounds, Reports on Progress in Physics 82, 016903 (2018).
  7. EPTA Collaboration and InPTA Collaboration, The second data release from the european pulsar timing array - iii. search for gravitational wave signals, A&A 678, A50 (2023).
  8. NANOGrav Collaboration, The nanograv 15 yr data set: Evidence for a gravitational-wave background, The Astrophysical Journal Letters 951, L8 (2023).
  9. PPTA Collaboration, Search for an isotropic gravitational-wave background with the parkes pulsar timing array, The Astrophysical Journal Letters 951, L6 (2023).
  10. C. Caprini and D. G. Figueroa, Cosmological backgrounds of gravitational waves, Classical and Quantum Gravity 35, 163001 (2018).
  11. T. Regimbau, The astrophysical gravitational wave stochastic background, Research in Astronomy and Astrophysics 11, 369 (2011).
  12. C. R. Contaldi, Anisotropies of Gravitational Wave Backgrounds: A Line Of Sight Approach, Phys. Lett. B 771, 9 (2017), arXiv:1609.08168 [astro-ph.CO] .
  13. G. Cusin, C. Pitrou, and J.-P. Uzan, Anisotropy of the astrophysical gravitational wave background: Analytic expression of the angular power spectrum and correlation with cosmological observations, Phys. Rev. D 96, 103019 (2017), arXiv:1704.06184 [astro-ph.CO] .
  14. A. C. Jenkins and M. Sakellariadou, Shot noise in the astrophysical gravitational-wave background, Phys. Rev. D 100, 063508 (2019).
  15. S. Mukherjee and J. Silk, Time-dependence of the astrophysical stochastic gravitational wave background, Mon. Not. Roy. Astron. Soc. 491, 4690 (2020), arXiv:1912.07657 [gr-qc] .
  16. M. R. Sah and S. Mukherjee, Non-stationary astrophysical stochastic gravitational-wave background: a new probe to the high-redshift population of binary black holes, Monthly Notices of the Royal Astronomical Society 527, 4100 (2023), https://academic.oup.com/mnras/article-pdf/527/2/4100/53789042/stad3365.pdf .
  17. A. C. Jenkins, J. D. Romano, and M. Sakellariadou, Estimating the angular power spectrum of the gravitational-wave background in the presence of shot noise, Phys. Rev. D 100, 083501 (2019b), arXiv:1907.06642 [astro-ph.CO] .
  18. LIGO Scientific Collaboration and Virgo Collaboration and KAGRA Collaboration, Upper limits on the isotropic gravitational-wave background from advanced ligo and advanced virgo’s third observing run, Phys. Rev. D 104, 022004 (2021b).
  19. L. Valbusa Dall’Armi, A. Ricciardone, and D. Bertacca, The dipole of the astrophysical gravitational-wave background, JCAP 11, 040, arXiv:2206.02747 [astro-ph.CO] .
  20. A. Ain, J. Suresh, and S. Mitra, Very fast stochastic gravitational wave background map making using folded data, Phys. Rev. D 98, 024001 (2018), arXiv:1803.08285 [gr-qc] .
  21. J. Suresh, A. Ain, and S. Mitra, Unified mapmaking for an anisotropic stochastic gravitational wave background, Phys. Rev. D 103, 083024 (2021), arXiv:2011.05969 [gr-qc] .
  22. A. Ain, P. Dalvi, and S. Mitra, Fast gravitational wave radiometry using data folding, Phys. Rev. D 92, 022003 (2015).
  23. E. S. Phinney, A practical theorem on gravitational wave backgrounds (2001), arXiv:astro-ph/0108028 [astro-ph] .
  24. LIGO Scientific Collaboration and Virgo Collaboration and KAGRA Collaboration, Folded data for first three observing runs of Advanced LIGO and Advanced Virgo, 10.5281/zenodo.6326656 (2022).
  25. LIGO Scientific Collaboration and Virgo Collaboration, Updated Advanced LIGO sensitivity design curve (2018).
  26. B. Allen and J. D. Romano, Detecting a stochastic background of gravitational radiation: Signal processing strategies and sensitivities, Phys. Rev. D 59, 102001 (1999).
  27. Planck Collaboration, Planck 2018 results. VI. Cosmological parameters, A&A 641, A6 (2020), arXiv:1807.06209 [astro-ph.CO] .
Citations (1)
View on Semantic Scholar

Summary

We haven't generated a summary for this paper yet.

Ai Sparkles Streamline Icon: https://streamlinehq.com Summarize Now