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Title: Expectations for Horizon-Scale Supermassive Black Hole Population Studies with the ngEHT
We present estimates for the number of supermassive black holes (SMBHs) for which the next-generation Event Horizon Telescope (ngEHT) can identify the black hole “shadow”, along with estimates for how many black hole masses and spins the ngEHT can expect to constrain using measurements of horizon-resolved emission structure. Building on prior theoretical studies of SMBH accretion flows and analyses carried out by the Event Horizon Telescope (EHT) collaboration, we construct a simple geometric model for the polarized emission structure around a black hole, and we associate parameters of this model with the three physical quantities of interest. We generate a large number of realistic synthetic ngEHT datasets across different assumed source sizes and flux densities, and we estimate the precision with which our defined proxies for physical parameters could be measured from these datasets. Under April weather conditions and using an observing frequency of 230 GHz, we predict that a “Phase 1” ngEHT can potentially measure ∼50 black hole masses, ∼30 black hole spins, and ∼7 black hole shadows across the entire sky.  more » « less
Award ID(s):
2034306 1935980
PAR ID:
10390980
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Galaxies
Volume:
10
Issue:
6
ISSN:
2075-4434
Page Range / eLocation ID:
109
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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