Improving PNLF Distance Measures with MUSE

The tension between the Hubble Constant derived from the distance ladder and that inferred from the early Universe has revitalized efforts to measure precise distances to galaxies in the Local Universe. Consequently, we have begun a program of using the ESO Multi Unit Spectroscopic Explorer (MUSE) integral-field unit spectrograph to measure [O III] 5007A Planetary Nebula Luminosity Function (PNLF) distances to galaxies as far away as ~ 50 Mpc. This would be more than twice the distance of any previous narrow-band PNLF measurement. In this initial investigation, we use archival MUSE data to measure the distances to 8 early-type galaxies between ~15 Mpc and ~30 Mpc using PN sample sizes between ~15 and ~150. We construct difference images in wavelength slices surrounding the [OIII] 5007A line, identify the PN, measure their [O III] line fluxes, and pay special attention to system uncertainties such as point-source aperture correction. Our goal is to demonstrate the accuracy of MUSE data for deriving PNLF distances in hopes of using the instrument to obtain a highly accurate and independent measurement of the Hubble Constant.