The Hubble Constant from Infrared Surface Brightness Fluctuation Distances

Abstract

We present a measurement of the Hubble constant H 0 from surface brightness fluctuation (SBF) distances for 63 bright, mainly early-type galaxies out to 100 Mpc observed with the Wide Field Camera 3 Infrared Channel (WFC3/IR) on the Hubble Space Telescope (HST ). The sample is drawn from several independent HST imaging programs that all used the WFC3/IR F110W (1.1 µm) bandpass. The distances reach the Hubble flow, with the majority of galaxies being in the 50-80 Mpc range. The median statistical uncertainty on individual measurements is 4%. We construct the IR SBF Hubble diagram with these distances and constrain H 0 using three different treatments of the galaxy velocities. For the SBF zero point calibration, we use both the existing tie to Cepheid variables, updated for consistency with the latest determination of the distance to the Large Magellanic Cloud from detached eclipsing binaries, and a new tie to the tip of the red giant branch (TRGB) calibrated from the maser distance to NGC 4258. These two SBF calibrations are consistent with each other and with theoretical predictions from stellar population models. From a weighted average of the Cepheid and TRGB calibrations, we derive H 0 = 73.3 ± 0.7 ± 2.4 km s −1 Mpc −1 , where the error bars reflect the statistical and systematic uncertainties. This result accords well with recent measurements of H 0 from Type Ia supernovae, time delays in multiply lensed quasars, and water masers. The systematic uncertainty could be reduced to below 2% by calibrating the SBF method with precision TRGB distances for a statistical sample of massive early-type galaxies out to the Virgo cluster measured with the James Webb Space Telescope.

On Larger $H_0$ Values in the CMB Dipole Direction

“…Evidently, a large Ω m causes the most immediate concern. However, this is an inference within flat ΛCDM and the latter is under scrutiny [1][2][3][4][5][6][7]. Note also that SN become sparse above z = 1, so the waters are largely uncharted, and we are reliant on QSO and Lyman-α BAO for guidance.…”

“…To that end, we retain the local QSOs, z < 0.1, which we combine with QSOs in the redshift range 0.7 < z < 1.479. 4 Throughout we use the flat priors 0 ≤ Ω m ≤ 1, 0 < β < 15, 0 < γ < 1 and 0 < δ < 1. As is clear from Table I, the results of extremisation and MCMC agree well, modulo the fact that Ω m is displaced to smaller values.…”

“…2 Note, within FLRW the value of H 0 is insensitive to the number of observables in any given direction, but of course the number of observables impacts the errors. Finally, a variation in H 0 across the sky recasts the Hubble tension discussion [1][2][3][4][5] as a symptom of a deeper issue.…”

“…Persistent cosmological tensions [1][2][3][4][5][6][7] suggest that it is timely to reflect on the success of the flat ΛCDM cosmology based on Planck values [8]. In particular, a ∼ 10% discrepancy in the scale of the Hubble parameter in the post Planck era, if true, belies the moniker "precision cosmology".…”

“…Without doubt, the bread and butter of FLRW cosmology is the Hubble parameter H(z). In particular, Hubble tension [1][2][3][4][5] casts a spotlight on H 0 = H(z = 0). Here, we build on earlier observations for strongly lensed QSOs [10] and Type Ia SN [34] that H 0 values in the direction of the CMB dipole, loosely defined, are larger.…”