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Title: A measurement of the Hubble constant from angular diameter distances to two gravitational lenses
The local expansion rate of the Universe is parametrized by the Hubble constant, H 0 , the ratio between recession velocity and distance. Different techniques lead to inconsistent estimates of H 0 . Observations of Type Ia supernovae (SNe) can be used to measure H 0 , but this requires an external calibrator to convert relative distances to absolute ones. We use the angular diameter distance to strong gravitational lenses as a suitable calibrator, which is only weakly sensitive to cosmological assumptions. We determine the angular diameter distances to two gravitational lenses, 810 − 130 + 160 and 1230 − 150 + 180 megaparsec, at redshifts z = 0.295 and 0.6304. Using these absolute distances to calibrate 740 previously measured relative distances to SNe, we measure the Hubble constant to be H 0 = 82.4 − 8.3 + 8.4 kilometers per second per megaparsec.  more » « less
Award ID(s):
1907396
NSF-PAR ID:
10185610
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
365
Issue:
6458
ISSN:
0036-8075
Page Range / eLocation ID:
1134 to 1138
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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