2021/05/21 by Holger Baumgardt, Eugene Vasiliev · 1 citation
Physics and Astronomy · #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stab1474
52 pages,29 figures, accepted for publication in MNRAS, Globular cluster data also available from http://people.smp.uq.edu.au/HolgerBaumgardt/globular/
arxiv created 2021/05/21 · arxiv updated 2021/07/14
We have derived accurate distances to Galactic globular clusters by combining data from the Gaia Early Data Release 3 with distances based on Hubble Space telescope HST data and literature based distances. We determine distances either directly from the Gaia EDR3 parallaxes, or kinematically by combining line-of-sight velocity dispersion profiles with Gaia EDR3 and HST based proper motion velocity dispersion profiles. We furthermore calculate cluster distances from fitting nearby subdwarfs, whose absolute luminosities we determine from their Gaia EDR3 parallaxes, to globular cluster main-sequences. We finally use HST based stellar number counts to determine distances. We find good agreement in the average distances derived from the different methods down to a level of about 2%. Combining all available data, we are able to derive distances to 162 Galactic globular clusters, with the distances to about 20 nearby globular clusters determined with an accuracy of 1% or better. We finally discuss the implications of our distances for the value of the local Hubble constant.