Kavli Affiliate: Wendy L. Freedman
| First 5 Authors: Wendy L. Freedman, Barry F. Madore, In Sung Jang, Taylor J. Hoyt, Abigail J. Lee
| Summary:
We present the latest results from the Chicago-Carnegie Hubble Program
(cchp) to measure the Hubble constant, using data from the James Webb Space
Telescope (JWST). The overall program aims to calibrate three independent
methods: (1) Tip of the Red Giant Branch (TRGB) stars, (2) JAGB (J-Region
Asymptotic Giant Branch) stars, and (3) Cepheids. To date, our program includes
10 nearby galaxies, hosting 11 Type Ia supernovae (SNe Ia) suitable for
measuring the Hubble constant ($H_0$). It also includes the galaxy NGC 4258,
whose geometric distance provides the zero-point calibration. In this paper we
discuss our results from the TRGB and JAGB methods. Our current best (highest
precision) estimate is $H_0$ = 70.39 $pm$ 1.22 (stat) $pm$ 1.33 (sys) $pm$
0.70 ($sigma_{SN}$), based on the TRGB method alone, with a total of 24 SN Ia
calibrators from both HST and JWST data. Based on our new JWST data only, and
tying into SNe Ia, we find values of $H_0$ = 68.81 $pm$ 1.79 (stat) $pm$ 1.32
(sys) for the TRGB, and $H_0$ = 67.80 $pm$ 2.17 (stat) $pm$ 1.64 (sys)
km/s/Mpc for the JAGB method. The distances measured using the TRGB and the
JAGB method agree, on average, at a level better than 1%, and with the SH0ES
Cepheid distances at just over the 1% level. Our results are consistent with
the current standard LambdaCDM model, without the need for the inclusion of
additional new physics. Future JWST data will be required to increase the
precision and accuracy of the local distance scale.
| Search Query: ArXiv Query: search_query=au:”Wendy L. Freedman”&id_list=&start=0&max_results=3