A 5 per cent measurement of the Hubble-Lemaître constant from Type II supernovae

The most stringent local measurement of the Hubble-Lemaître constant from Cepheid-calibrated Type Ia supernovae (SNe Ia) differs from the value inferred via the cosmic microwave background radiation (Planck+ΛCDM) by ∼5σ. This so-called Hubble tension has been confirmed by other independent methods, and thus does not appear to be a possible consequence of systematic errors. Here, we continue upon our prior work of using Type II supernovae to provide another, largely independent method to measure the Hubble-Lemaître constant. From 13 SNe II with geometric, Cepheid, or tip of the red giant branch (TRGB) host-galaxy distance measurements, we derive H$_0= 75.4^{+3.8}_{-3.7}$ km s-1 Mpc-1 (statistical errors only), consistent with the local measurement but in disagreement by ∼2.0σ with the Planck+ΛCDM value. Using only Cepheids (N = 7), we find H$_0 = 77.6^{+5.2}_{-4.8}$ km s-1 Mpc-1, while using only TRGB (N = 5), we derive H$_0 = 73.1^{+5.7}_{-5.3}$ km s-1 Mpc-1. Via 13 variants of our data set, we derive a systematic uncertainty estimate of 1.5 km s-1 Mpc-1. The median value derived from these variants differs by just 0.3 km s-1 Mpc-1 from that produced by our fiducial model. Because we only replace SNe Ia with SNe II - and we do not find statistically significant difference between the Cepheid and TRGB H0 measurements - our work reveals no indication that SNe Ia or Cepheids could be the sources of the 'H0 tension.' We caution, however, that our conclusions rest upon a modest calibrator sample; as this sample grows in the future, our results should be verified.NSF grants AST-1908952 and AST-1911074. LG acknowledges financial support from the Spanish Ministerio de Ciencia e Innovación (MCIN), the Agencia Estatal de Investigación (AEI) 10.13039/501100011033, and the European Social Fund (ESF) ‘Investing in your future’ under the 2019 Ramón y Cajal program RYC2019-027683-I and the PID2020-115253GA-I00 HOSTFLOWS project, from Centro Superior de Investigaciones Científicas (CSIC) under the PIE project 20215AT016, and the program Unidad de Excelencia María de Maeztu CEX2020-001058-M. Support for AVF’s supernova research at U.C. Berkeley has been provided by the NSF through grant AST-1211916, the TABASGO Foundation, Gary and Cynthia Bengier, Marc J. Staley (whose fellowship partially funded B.E.S. while contributing to the work presented herein as a graduate student), the Christopher R. Redlich Fund, the Sylvia and Jim Katzman Foundation, and the Miller Institute for Basic Research in Science (AVF was a Miller Senior Fellow). BJS was supported by U.S. NSF grants AST-1907570, AST-1908952, AST-1920392, and AST-1911074. The work of the CSP-I has been supported by the U.S. NSF under grants AST-0306969, AST-0607438, and AST-1008343