The Most Massive Binary Black Hole Detections and the Identification of Population Outliers

Abstract

Advanced LIGO and Virgo detected ten binary black holes (BBHs) in their first two observing runs (O1 and O2). Analysis of these events found strong evidence for a dearth of BBHs with component masses greater than $\sim 45M_{\odot }$, as would be expected from a pair-instability mass gap. Meanwhile, a standalone analysis of the merger GW170729 found its primary mass $m_1=51.2_{-11.0}^{+16.2}{M}_{\odot }$, with the majority of its posterior support at $m_1>45M_{\odot }$. Although this appears to be in contradiction with the existence of a limit at $\sim 45M_{\odot }$, we argue that individual events cannot be evaluated without reference to the entire population. When GW170729 is analyzed jointly with the rest of the detections, as part of a full hierarchical population analysis, its inferred primary mass tightens considerably, to $m_1=38.9_{-4.5}^{+7.3}{M}_{\odot }$. For a large sample of events in the presence of noise, apparent outliers in the detected distribution are inevitable, even if the underlying population forbids outliers. We discuss methods of distinguishing between statistical fluctuations and population outliers using posterior predictive tests. Applying these tests to the primary mass distribution in O1 and O2, we find that the ten detections are consistent with even the simplest power-law plus maximum-mass model considered by the LVC. This supports the claim that GW170729 is not a population outlier. We also provide non-parametric constraints on the rate of high-mass mergers and conservatively bound the rate of mergers with $m_1>45M_{\odot }$ at $2.8_{-2.0}^{+5.4}\%$ of the total merger rate. After 100 detections like those of O1 and O2 from a population with a maximum primary mass of $45M_{\odot }$, it would be common for the most massive system to have an observed maximum-likelihood mass $m_1\gtrsim 70M_{\odot }$.

References in corpus (14)

• Advanced Virgo: a 2nd generation interferometric gravitational wave detector
• Robust parameter estimation for compact binaries with ground-based gravitational-wave observations using the LALInference software library
• Double Compact Objects III: Gravitational Wave Detection Rates
• MOCCA-SURVEY Database I: Coalescing Binary Black Holes Originating From Globular Clusters
• Illuminating Black Hole Binary Formation Channels with Spins in Advanced LIGO
• Exoplanet population inference and the abundance of Earth analogs from noisy, incomplete catalogs
• The Masses and Spins of Neutron Stars and Stellar-Mass Black Holes
• Inferring the eccentricity distribution
• A Future Percent-Level Measurement of the Hubble Expansion at Redshift 0.8 With Advanced LIGO
• Where are LIGO's Big Black Holes?
• Search for gravitational lensing signatures in LIGO-Virgo binary black hole events
• Model-independent inference on compact-binary observations
• Dynamical Formation of Low-Mass Merging Black Hole Binaries like GW151226
• A dynamical gravitational wave source in a dense cluster

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• You Can't Always Get What You Want: The Impact of Prior Assumptions on Interpreting GW190412
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• Astrophysical implications of GW190412 as a remnant of a previous black-hole merger
• Lensing or luck? False alarm probabilities for gravitational lensing of gravitational waves
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• A Search for Gravitational Waves from Binary Mergers with a Single Observatory
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• Sampling the full hierarchical population posterior distribution in gravitational-wave astronomy
• The astrophysical odds of GW151216
• Targeted modeling of GW150914's binary black hole source with dart_board
• Assessing gravitational-wave binary black hole candidates with Bayesian odds
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• Detection of LIGO-Virgo binary black holes in the pair-instability mass gap
• One to many: comparing single gravitational-wave events to astrophysical populations
• Calibrating signal-to-noise ratio detection thresholds using gravitational-wave catalogs
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• Measurement prospects for the pair-instability mass cutoff with gravitational waves
• Gravitational-wave astronomy requires population-informed parameter estimation
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• Inferring binary black holes stellar progenitors with gravitational wave sources
• Vanishing Compactness Gap and Fermionic Compact Dark Matter in Hořava-Lifshitz Gravity
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