Results 21 to 30 of about 114,518 (203)
Andromeda’s Parachute: Time Delays and Hubble Constant
The Astrophysical Journal, 2023 The gravitational lens system PS J0147+4630 (Andromeda’s Parachute) consists of four quasar images ABCD and a lensing galaxy. We obtained r -band light curves of ABCD in the 2017−2022 period from monitoring with two 2 m class telescopes.
Vyacheslav N. Shalyapin +3 more
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The Astrophysical Journal Letters, 2023 We establish a cosmological-model-independent method to determine the Hubble constant H _0 from the localized fast radio bursts (FRBs) and the Hubble parameter measurements from cosmic chronometers and obtain a first such determination H _0 = 71 ± 3 km s
Yang Liu, Hongwei Yu, Puxun Wu
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The Unsettled Number: Hubble’s Tension
Universe, 2023 One of main sources of uncertainty in modern cosmology is the present rate of the universe’s expansion, H0, called the Hubble constant. Once again, different observational techniques bring about different results, causing new “Hubble tension”.
Jorge L. Cervantes-Cota +2 more
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THE 1% CONCORDANCE HUBBLE CONSTANT [PDF]
The Astrophysical Journal, 2014 9 pages, 4 figures, v2 reformatted in emulateapj, updated to match accepted ...
Bennett, C. L. +3 more
openaire +2 more sources
Why reducing the cosmic sound horizon alone can not fully resolve the Hubble tension
Communications Physics, 2021 It is generally accepted that the Universe is dominated by dark energy but the different methods to measure the Hubble constant disagree, giving origin to what is known as the "Hubble tension”. The authors demonstrate that the sole reduction of the sound
Karsten Jedamzik +2 more
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Hubble Tension: The Evidence of New Physics
Universe, 2023 The ΛCDM model provides a good fit to most astronomical observations but harbors large areas of phenomenology and ignorance. With the improvements in the precision and number of observations, discrepancies between key cosmological parameters of this ...
Jian-Ping Hu, Fa-Yin Wang
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The redshift of the gravitationally lensed radio source PKS1830-211 [PDF]
, 1999 We report on the spectroscopic identification and the long awaited redshift measurement of the heavily obscured, gravitationally lensed radio source PKS 1830-211, which was first observed as a radio Einstein ring.
B. Frye +11 more
core +2 more sources
Publications of the Astronomical Society of Australia, 2000 AbstractWith the completion of the Hubble Space Telescope (HST) Key Project on the Extragalactic Distance Scale, it is interesting to form the dimensionless quantity H0t0 by multiplying the Hubble Constant by the age of the Universe. In a matter dominated decelerating Universe with a density exceeding 0·26 of the critical value, H0t0 < 1; in an ...
openaire +2 more sources
Hubble constant hunter’s guide [PDF]
Physical Review D, 2020 Measurements of the Hubble constant and, more generally, measurements of the expansion rate and distances over the interval $0lzl1$ appear to be inconsistent with the predictions of the standard cosmological model ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) given observations of cosmic microwave background temperature and polarization anisotropies ...
L. Knox, M. Millea
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Galaxy Clusters: Oblate or Prolate? [PDF]
, 1999 It is now well known that a combined analysis of the Sunyaev-Zel'dovich (SZ) effect and the X-ray emission observations can be used to determine the angular diameter distance to galaxy clusters, from which the Hubble constant is derived.
Asantha R. Cooray +23 more
core +4 more sources