Spectral sirens: cosmology from the full mass distribution of compact binaries

Abstract

We explore the use of the mass spectrum of neutron stars and black holes in gravitational-wave compact binary sources as a cosmological probe. These standard siren sources provide direct measurements of luminosity distance. In addition, features in the mass distribution, such as mass gaps or peaks, will redshift, and thus provide independent constraints on their redshift distribution. We argue that the mass spectrum of LIGO/Virgo/KAGRA events introduces at least five independent mass "features": the upper and lower edges of the pair instability supernova (PISN) gap, the upper and lower edges of the neutron star-black hole gap, and the minimum neutron star mass. We find that the PISN gap dominates the cosmological inference with current detectors (2G), as shown in previous work. We further argue that the lower mass gap will provide the most powerful constraints in the era of Cosmic Explorer and Einstein Telescope (3G). We demonstrate that degeneracies between redshift evolution of the source masses and cosmology can be broken, unless an astrophysical conspiracy shifts all features of the full mass distribution simultaneously following the (non-trivial) Hubble diagram evolution. We find that this "spectral siren" method has the potential to constrain both cosmology and the evolution of the mass distribution, with 2G achieving better than 10% precision on H(z) at z 1 within a year, and 3G reaching 1% at z 2 within one month.

Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies

“…Among the sources without electromagnetic counterpart (called dark standard sirens), either by using the statistical host identification technique [1821,1822], or using the spatial cross-correlation [1823][1824][1825] of the GW sources with spectroscopic galaxies detectable from DESI and SPHEREx [1826], one can achieve a similar precision with a few thousands of dark sirens from the future detector network. The dark siren measurement of the expansion history may also be possible from the mass spectrum of binary black holes by using a few hundreds of sources, if the mass spectrum can be standardized [1827][1828][1829][1830].…”

“…It follows that for the success of dark GWSS appropriate full sky galaxy catalogs that cover the redshift range of GW sources are required. Alternatively, it is possible to use features in the mass spectrum of binary black holes to infer redshift, providing a powerful and independent standard siren probe of cosmology [211,1827,1829,1830,1979,1980]. These "spectral sirens" may provide percent-level constraints on the expansion history at z ∼ 1 and beyond.…”

Binary black holes population and cosmology in new lights: Signature of PISN mass and formation channel in GWTC-3

“…The mass distribution of the BBHs can also play an important role in inferring the cosmic expansion history (Taylor et al 2012;Farr et al 2019;Mastrogiovanni et al 2021a;You et al 2021;Mancarella et al 2021;Mukherjee 2021;Leyde et al 2022;Ezquiaga & Holz 2022). As the masses of the GW sources are redshifted (m det = (1 + z)m), one can expect to infer the redshift from the mass distribution of the GW sources, if the mass distribution of the BBHs can exhibit a universal property or at least a standardized behavior.…”

“…We can break the mass-redshift degeneracy and infer the cosmic expansion history from dark standard sirens without applying the cross-correlation technique (Oguri 2016;Mukherjee & Wandelt 2018;Mukherjee et al 2020Mukherjee et al , 2021aBera et al 2020;Scelfo et al 2020;Mukherjee et al 2021b;Cañas-Herrera et al 2021;Scelfo et al 2022;Cigarrán Díaz & Mukherjee 2022;Mukherjee et al 2022) or statistical host identification technique (Schutz 1986;MacLeod & Hogan 2008;Del Pozzo 2012;Arabsalmani et al 2013;Gray et al 2020;Fishbach et al 2019;Abbott et al 2021e;Soares-Santos et al 2019;Finke et al 2021;Abbott et al 2020b;Palmese et al 2021). However, if BBHs mass distribution exhibits redshift dependence due to its intrinsic dependence on the delay time distribution, then cosmic redshifts cannot be accurately inferred (Mukherjee 2021;Ezquiaga & Holz 2022), and it can bias the results if the redshift dependence of the mass distribution is not considered. Exploring the merger rate distribution to explore cosmology from dark sirens is also studied for the third generation GW detectors (Ding et al 2019;Ye & Fishbach 2021;Leandro et al 2022).…”

Uncertainty and bias of cosmology and astrophysical population model from statistical dark sirens

“…Initially, the statistical inference was done by comparing a BBH event catalog with galaxy catalogs (e.g., Schutz 1986;Chen et al 2018;Fishbach et al 2019;Finke et al 2021). Later, people realized that features in the mass distribution of BBH events could also be used to constrain the cosmological parameters (e.g., Chernoff & Finn 1993;Taylor et al 2012;Farr et al 2019;Mastrogiovanni et al 2021;LIGO Scientific Collaboration et al 2021d;María Ezquiaga & Holz 2022). In both cases, one computes the likelihood of each event to happen given a set of cosmological parameters as well as an assumed astrophysical population model.…”