Quasi-universal Behavior of the Threshold Mass in Unequal-mass, Spinning Binary Neutron Star Mergers
Abstract
The lifetime of the remnant produced by the merger of two neutron stars can provide a wealth of information on the equation of state of nuclear matter and on the processes leading to the electromagnetic counterpart. Hence, it is essential to determine when this lifetime is the shortest, corresponding to when the remnant has a mass equal to the threshold mass, Mₜₕ, to prompt collapse to a black hole. We report on the results of more than 360 simulations of merging neutron-star binaries covering 40 different configurations differing in mass ratio and spin of the primary. Using this data, we have derived a quasi-universal relation for Mₜₕ and expressed its dependence on the mass ratio and spin of the binary. The new expression recovers the results of Koeppel et al. for equal-mass, irrotational binaries and reveals that Mₜₕ can increase (decrease) by 5% (10%) for binaries that have spins aligned (antialigned) with the orbital angular momentum and provides evidence for a nonmonotonic dependence of Mₜₕ on the mass asymmetry in the system. Finally, we extend to unequal masses and spinning binaries the lower limits that can be set on the stellar radii once a neutron star binary is detected, illustrating how the merger of an unequal-mass, rapidly spinning binary can significantly constrain the allowed values of the stellar radii.
Additional Information
© 2021. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. L.R. acknowledges the support by the State of Hesse within the Research Cluster ELEMENTS (Project ID 500/10.006). E.R.M. acknowledges support from the Princeton Center for Theoretical Science, the Princeton Gravity Initiative, and the Institute for Advanced Study. The simulations were performed on HPE Apollo Hawk at the High Performance Computing Center Stuttgart (HLRS) under the grants BBHDISKS and BNSMIC, and on SuperMUC at the Leibniz Supercomputing Centre. Software: Einstein Toolkit (Loeffler et al. 2012), Carpet (Schnetter et al. 2004), FIL (Etienne et al. 2015; Most et al. 2019b), FUKA (Papenfort et al. 2021), Kadath (Grandclement 2010).Attached Files
Published - Tootle_2021_ApJL_922_L19.pdf
Files
Name | Size | Download all |
---|---|---|
md5:5d7cc971f9259703d0f24554f80639b4
|
1.5 MB | Preview Download |
Additional details
- Eprint ID
- 121216
- Resolver ID
- CaltechAUTHORS:20230501-297157000.32
- 500/10.006
- State of Hesse
- Princeton University
- Institute for Advanced Study
- Created
-
2023-05-04Created from EPrint's datestamp field
- Updated
-
2023-05-04Created from EPrint's last_modified field