%0 Generic %1 pesce2020megamaser %A Pesce, D. W. %A Braatz, J. A. %A Reid, M. J. %A Riess, A. G. %A Scolnic, D. %A Condon, J. J. %A Gao, F. %A Henkel, C. %A Impellizzeri, C. M. V. %A Kuo, C. Y. %A Lo, K. Y. %D 2020 %K tifr %T The Megamaser Cosmology Project. XIII. Combined Hubble constant constraints %U http://arxiv.org/abs/2001.09213 %X We present a measurement of the Hubble constant made using geometric distance measurements to megamaser-hosting galaxies. We have applied an improved approach for fitting maser data and obtained better distance estimates for four galaxies previously published by the Megamaser Cosmology Project: UGC 3789, NGC 6264, NGC 6323, and NGC 5765b. Combining these updated distance measurements with those for the maser galaxies CGCG 074-064 and NGC 4258, and assuming a fixed velocity uncertainty of 250 km s$^-1$ associated with peculiar motions, we constrain the Hubble constant to be $H_0 = 73.9 3.0$ km s$^-1$ Mpc$^-1$ independent of distance ladders and the cosmic microwave background. This best value relies solely on maser-based distance and velocity measurements, and it does not use any peculiar velocity corrections. Different approaches for correcting peculiar velocities do not modify $H_0$ by more than $\pm1\sigma$, with the full range of best-fit Hubble constant values spanning 71.8-76.9 km s$^-1$ Mpc$^-1$. We corroborate prior indications that the local value of $H_0$ exceeds the early-Universe value, with a confidence level varying from 95-99% for different treatments of the peculiar velocities.

@misc{pesce2020megamaser, abstract = {We present a measurement of the Hubble constant made using geometric distance measurements to megamaser-hosting galaxies. We have applied an improved approach for fitting maser data and obtained better distance estimates for four galaxies previously published by the Megamaser Cosmology Project: UGC 3789, NGC 6264, NGC 6323, and NGC 5765b. Combining these updated distance measurements with those for the maser galaxies CGCG 074-064 and NGC 4258, and assuming a fixed velocity uncertainty of 250 km s$^{-1}$ associated with peculiar motions, we constrain the Hubble constant to be $H_0 = 73.9 \pm 3.0$ km s$^{-1}$ Mpc$^{-1}$ independent of distance ladders and the cosmic microwave background. This best value relies solely on maser-based distance and velocity measurements, and it does not use any peculiar velocity corrections. Different approaches for correcting peculiar velocities do not modify $H_0$ by more than ${\pm}1{\sigma}$, with the full range of best-fit Hubble constant values spanning 71.8-76.9 km s$^{-1}$ Mpc$^{-1}$. We corroborate prior indications that the local value of $H_0$ exceeds the early-Universe value, with a confidence level varying from 95-99% for different treatments of the peculiar velocities.}, added-at = {2020-01-28T05:29:02.000+0100}, author = {Pesce, D. W. and Braatz, J. A. and Reid, M. J. and Riess, A. G. and Scolnic, D. and Condon, J. J. and Gao, F. and Henkel, C. and Impellizzeri, C. M. V. and Kuo, C. Y. and Lo, K. Y.}, biburl = {https://www.bibsonomy.org/bibtex/2eee953e91c38389de26bc365439e9e45/citekhatri}, description = {The Megamaser Cosmology Project. XIII. Combined Hubble constant constraints}, interhash = {154033ed3202a4b1d9104414982a1644}, intrahash = {eee953e91c38389de26bc365439e9e45}, keywords = {tifr}, note = {cite arxiv:2001.09213Comment: 13 pages, 1 figure, submitted to ApJL}, timestamp = {2020-01-28T05:29:02.000+0100}, title = {The Megamaser Cosmology Project. XIII. Combined Hubble constant constraints}, url = {http://arxiv.org/abs/2001.09213}, year = 2020 }