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Title: Science-driven Tunable Design of Cosmic Explorer Detectors
Abstract

Ground-based gravitational-wave detectors like Cosmic Explorer (CE) can be tuned to improve their sensitivity at high or low frequencies by tuning the response of the signal extraction cavity. Enhanced sensitivity above 2 kHz enables measurements of the post-merger gravitational-wave spectrum from binary neutron star mergers, which depends critically on the unknown equation of state of hot, ultra-dense matter. Improved sensitivity below 500 Hz favors precision tests of extreme gravity with black hole ringdown signals and improves the detection prospects while facilitating an improved measurement of source properties for compact binary inspirals at cosmological distances. At intermediate frequencies, a more sensitive detector can better measure the tidal properties of neutron stars. We present and characterize the performance of tuned CE configurations that are designed to optimize detections across different astrophysical source populations. These tuning options give CE the flexibility to target a diverse set of science goals with the same detector infrastructure. We find that a 40 km CE detector outperforms a 20 km in all key science goals other than access to post-merger physics. This suggests that CE should include at least one 40 km facility.

Authors:
; ; ; ; ; ; ; ;
Award ID(s):
2110441 2012083 2006384 1836779 1806962
Publication Date:
NSF-PAR ID:
10367137
Journal Name:
The Astrophysical Journal
Volume:
931
Issue:
1
Page Range or eLocation-ID:
Article No. 22
ISSN:
0004-637X
Publisher:
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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