Intrinsic tension in the supernova sector of the local Hubble constant measurement and its implications
arXiv:2206.08160 · doi:10.1093/mnras/stac1878
Abstract
We reanalyse observations of type Ia supernovae (SNe) and Cepheids used in the local determination of the Hubble constant and find strong evidence that SN standardisation in the calibration sample (galaxies with observed Cepheids) require a steeper slope of the colour correction than in the cosmological sample (galaxies in the Hubble flow). The colour correction in the calibration sample is consistent with being entirely due to an extinction correction due to dust with properties similar to that of the Milky Way (R_B~4.6+/-0.4) and there is no evidence for intrinsic scatter in the SN peak magnitudes. An immediate consequence of this finding is that the local measurement of the Hubble constant becomes dependent on the choice of SN reference colour, i.e., the colour of an unreddened SN. Specifically, the Hubble constant inferred from the same observations decreases gradually with the reference colour assumed in the SN standardisation. We recover the Hubble constant measured by SH0ES for the standard choice of reference colour (SALT2 colour parameter c=0) while for a reference colour which coincides with the blue end of the observed SN colour distribution (c~-0.13), the Hubble constant from Planck observations of the CMB (assuming a flat LCDM cosmological model) is recovered. These results are intriguing in that they may provide an avenue for resolving the Hubble tension. However, since there is no obvious physical basis for the differences in colour corrections in the two SN samples, the origin of these require further investigations.
12 pages, 4 figures, 3 tables; accepted for publication in MNRAS
References in corpus (12)
- In the Realm of the Hubble tension a Review of Solutions
- Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics Beyond LambdaCDM
- Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM
- A distance to the Large Magellanic Cloud that is precise to one per cent
- TDCOSMO IV: Hierarchical time-delay cosmography -- joint inference of the Hubble constant and galaxy density profiles
- Cosmological parameters from the comparison of peculiar velocities with predictions from the 2M++ density field
- To H0 or not to H0?
- On the use of the local prior on the absolute magnitude of Type Ia supernovae in cosmological inference
- It's Dust: Solving the Mysteries of the Intrinsic Scatter and Host-Galaxy Dependence of Standardized Type Ia Supernova Brightnesses
- Measuring the Hubble constant with Type Ia supernovae as near-infrared standard candles
- A new measurement of the Hubble constant using Type Ia supernovae calibrated with surface brightness fluctuations
- Testing the Consistency of Dust Laws in SN Ia Host Galaxies: A BayeSN Examination of Foundation DR1