---
_id: '17680'
abstract:
- lang: eng
  text: The advent of time domain astronomy is revolutionizing our understanding of
    the universe. Programs such as the Catalina Real-time Transient Survey (CRTS)
    or the Palomar Transient Factory (PTF) surveyed millions of objects for several
    years, allowing variability studies on large statistical samples. The inspection
    of ≈250 k quasars in CRTS resulted in a catalog of 111 potentially periodic sources,
    put forward as supermassive black hole binary (SMBHB) candidates. A similar investigation
    on PTF data yielded 33 candidates from a sample of ≈35 k quasars. Working under
    the SMBHB hypothesis, we compute the implied SMBHB merger rate and we use it to
    construct the expected gravitational wave background (GWB) at nano-Hz frequencies,
    probed by pulsar timing arrays (PTAs). After correcting for incompleteness and
    assuming virial mass estimates, we find that the GWB implied by the CRTS sample
    exceeds the current most stringent PTA upper limits by almost an order of magnitude.
    After further correcting for the implicit bias in virial mass measurements, the
    implied GWB drops significantly but is still in tension with the most stringent
    PTA upper limits. Similar results hold for the PTF sample. Bayesian model selection
    shows that the null hypothesis (whereby the candidates are false positives) is
    preferred over the binary hypothesis at about 2.3σ and 3.6σ for the CRTS and PTF
    samples respectively. Although not decisive, our analysis highlights the potential
    of PTAs as astrophysical probes of individual SMBHB candidates and indicates that
    the CRTS and PTF samples are likely contaminated by several false positives.
article_number: '42'
article_processing_charge: No
article_type: original
author:
- first_name: Alberto
  full_name: Sesana, Alberto
  last_name: Sesana
- first_name: Zoltán
  full_name: Haiman, Zoltán
  id: 7c006e8c-cc0d-11ee-8322-cb904ef76f36
  last_name: Haiman
- first_name: Bence
  full_name: Kocsis, Bence
  last_name: Kocsis
- first_name: Luke Zoltan
  full_name: Kelley, Luke Zoltan
  last_name: Kelley
citation:
  ama: 'Sesana A, Haiman Z, Kocsis B, Kelley LZ. Testing the binary hypothesis: Pulsar
    timing constraints on supermassive black hole binary candidates. <i>The Astrophysical
    Journal</i>. 2018;856(1). doi:<a href="https://doi.org/10.3847/1538-4357/aaad0f">10.3847/1538-4357/aaad0f</a>'
  apa: 'Sesana, A., Haiman, Z., Kocsis, B., &#38; Kelley, L. Z. (2018). Testing the
    binary hypothesis: Pulsar timing constraints on supermassive black hole binary
    candidates. <i>The Astrophysical Journal</i>. American Astronomical Society. <a
    href="https://doi.org/10.3847/1538-4357/aaad0f">https://doi.org/10.3847/1538-4357/aaad0f</a>'
  chicago: 'Sesana, Alberto, Zoltán Haiman, Bence Kocsis, and Luke Zoltan Kelley.
    “Testing the Binary Hypothesis: Pulsar Timing Constraints on Supermassive Black
    Hole Binary Candidates.” <i>The Astrophysical Journal</i>. American Astronomical
    Society, 2018. <a href="https://doi.org/10.3847/1538-4357/aaad0f">https://doi.org/10.3847/1538-4357/aaad0f</a>.'
  ieee: 'A. Sesana, Z. Haiman, B. Kocsis, and L. Z. Kelley, “Testing the binary hypothesis:
    Pulsar timing constraints on supermassive black hole binary candidates,” <i>The
    Astrophysical Journal</i>, vol. 856, no. 1. American Astronomical Society, 2018.'
  ista: 'Sesana A, Haiman Z, Kocsis B, Kelley LZ. 2018. Testing the binary hypothesis:
    Pulsar timing constraints on supermassive black hole binary candidates. The Astrophysical
    Journal. 856(1), 42.'
  mla: 'Sesana, Alberto, et al. “Testing the Binary Hypothesis: Pulsar Timing Constraints
    on Supermassive Black Hole Binary Candidates.” <i>The Astrophysical Journal</i>,
    vol. 856, no. 1, 42, American Astronomical Society, 2018, doi:<a href="https://doi.org/10.3847/1538-4357/aaad0f">10.3847/1538-4357/aaad0f</a>.'
  short: A. Sesana, Z. Haiman, B. Kocsis, L.Z. Kelley, The Astrophysical Journal 856
    (2018).
date_created: 2024-09-06T08:06:14Z
date_published: 2018-03-22T00:00:00Z
date_updated: 2024-09-25T09:02:27Z
day: '22'
doi: 10.3847/1538-4357/aaad0f
extern: '1'
intvolume: '       856'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.3847/1538-4357/aaad0f
month: '03'
oa: 1
oa_version: Published Version
publication: The Astrophysical Journal
publication_identifier:
  issn:
  - 0004-637X
  - 1538-4357
publication_status: published
publisher: American Astronomical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Testing the binary hypothesis: Pulsar timing constraints on supermassive black
  hole binary candidates'
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 856
year: '2018'
...