Document Type
Article
Publication Date
12-1-2017
Abstract
On 2017 August 17 the merger of two compact objects with masses consistent with two neutron stars was discovered through gravitational-wave (GW170817), gamma-ray (GRB 170817A), and optical (SSS17a/AT 2017gfo) observations. The optical source was associated with the early-type galaxy NGC 4993 at a distance of just ∼40 Mpc, consistent with the gravitational-wave measurement, and the merger was localized to be at a projected distance of ∼2 kpc away from the galaxy's center. We use this minimal set of facts and the mass posteriors of the two neutron stars to derive the first constraints on the progenitor of GW170817 at the time of the second supernova (SN). We generate simulated progenitor populations and follow the three-dimensional kinematic evolution from binary neutron star (BNS) birth to the merger time, accounting for pre-SN galactic motion, for considerably different input distributions of the progenitor mass, pre-SN semimajor axis, and SN-kick velocity. Though not considerably tight, we find these constraints to be comparable to those for Galactic BNS progenitors. The derived constraints are very strongly influenced by the requirement of keeping the binary bound after the second SN and having the merger occur relatively close to the center of the galaxy. These constraints are insensitive to the galaxy's star formation history, provided the stellar populations are older than 1 Gyr.
Recommended Citation
Abbott, Benjamin P., Robert Abbott, T. D. Abbott, Fausto Acernese, K. Ackley, C. Adams, T. Adams et al. "On the progenitor of binary neutron star merger GW170817." The Astrophysical Journal Letters 850, no. 2 (2017): L40. http://doi.org/10.3847/2041-8213/aa93fc
Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.
Publication Title
Astrophysical Journal Letters
DOI
10.3847/2041-8213/aa93fc
Comments
Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI
Original version available at: http://doi.org/10.3847/2041-8213/aa93fc