6 papers
Chromatic Effects Across the Roman Focal Plane: Implications for Supernova Photometry and Measurements of Cosmological Parameters
Rujuta Purohit, Dillon Brout, Daniel Scolnic +14
Calibration uncertainties are the leading systematics in cosmological analyses using Type Ia supernovae (SNe Ia). For the \textit{Nancy Grace Roman Space Telescope (Roman)}, we qua…
Converging on the Cepheid Metallicity Dependence: Implications of Non-Standard Gaia Parallax Recalibration on Distance Measures
Louise Breuval, Gagandeep S. Anand, Richard I. Anderson +20
By comparing Cepheid brightnesses with geometric distance measures including Gaia EDR3 parallaxes, most recent analyses conclude metal-rich Cepheids are brighter, quantified as $γ…
The Perfect Host: JWST Cepheid Observations in a Background-Free SN Ia Host Confirm No Bias in Hubble-Constant Measurements
Adam G. Riess, Siyang Li, Gagandeep S. Anand +8
Cycle 1 JWST observations of Cepheids in SN Ia hosts resolved their red-giant-dominated NIR backgrounds, sharply reducing crowding and showing that photometric bias in lower-resolu…
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…
JAGB 2.0: Improved Constraints on the J-region Asymptotic Giant Branch-based Hubble Constant from an Expanded Sample of JWST Observations
Siyang Li, Adam G. Riess, Daniel Scolnic +2
The J-region Asymptotic Giant Branch (JAGB) is an overdensity of stars in the near-infrared, attributed to carbon-rich asymptotic giant branch stars, and recently used as a standar…
JWST Validates HST Distance Measurements: Selection of Supernova Subsample Explains Differences in JWST Estimates of Local H0
Adam G. Riess, Dan Scolnic, Gagandeep S. Anand +16
JWST provides new opportunities to cross-check the HST Cepheid/SNeIa distance ladder, which yields the most precise local measure of H0. We analyze early JWST subsamples (~1/4 of t…