A Population II TRGB-SBF Route to H0 with HST and JWST
Brent Tully (University of Hawaii)
Monday 13/05/2024 @ 11:30, Sala Antonio Sollima (IV piano Battiferro)
The Population I cepheid-supernova path to a value of the Hubble constant can be complemented by an equally accurate Population II path coupling the tip of the red giant branch and surface brightness fluctuation methodologies. Programs with HST are now being carried forth with JWST. The linkage between TRGB and SBF can be made with simultaneous observations of the high surface brightness cores and low surface brightness halos on individual early-type galaxies with JWST NIRCam. Further SBF observations can be made to large numbers of targets at redshifts in the Hubble flow regime. Preliminary results will be presented across the full range from zero-point calibration to the TRGB-SBF transfer to distances acquired at z=0.03.