An improved standardization framework for Type II-P supernovae using a hierarchical Bayesian approach
Year: 2026
Type: article
Abstract: We used observed as part of the experiment as standardizable candles to develop an improved standardization framework. These candles consist of spectrophotometric measurements of low-redshift SNe in the wavelength range 3200 < łambda < 10000,Å using a two-channel integral field optical spectrograph, featuring host galaxy subtraction through follow-up observations and an accurate flux calibration. The quality and homogeneous nature of the measured dataset makes it unique and well suited for use in the SN II-P sneIIp snfactory scm . We developed an improved method for determining the expansion velocities of based on Gaussian process regression. We extended the conventional by an additional correction term containing the H_α absorption-to-emission ratio and a hierarchical Bayesian framework. The additional correction improved the quality of the standardization, particularly around 30 to 40 days after the explosion. We were also able to reduce the scatter of the Hubble-flow from 0.28,mag to 0.18,mag compared to previous work. As an example application of this method, we measured H_0 using a preexisting calibrator sample of SNe II with Cepheid- or sneIIp scm sneIIp trgb -based distance moduli. We found a value of H_0 = 70.6^ +4.5 _ -4.3 ,km,s-1,Mpc^-1, which only includes the statistical uncertainty and corresponds to a precision of 6.2,%. We found variations of 1.4,km,s-1,Mpc^ -1 between hierarchical model variations. This is well within our quoted statistical uncertainty. In contrast, without the additional correction term, we obtained H_0 = 73.0^ +6.9 _ -6.1 ,km,s-1,Mpc^-1 (a reduced precision of 8.9,%), which highlights the improved precision of our new method. We identify and discuss inconsistencies between the measured parent populations of the calibrator and Hubble-flow standardization characteristics that are present in this and literature samples that are not explained by a simple selection on magnitude and that will need to be improved upon as sneIIp samples grow.
Source: Astronomy and Astrophysics
Authors: A. Holas, S. Taubenberger, C. Vogl, D. Rubin, M. Vincenzi, W. Hillebrandt, G. Aldering, P. Antilogus, C. Aragon, S. Bailey, C. Baltay, S. Benitez-Herrera, S. Bongard, K. Boone, C. Buton, G. Csörnyei, Y. Copin, S. Dixon, M. Fink, D. Fouchez, E. Gangler, R. Gupta, B. Hayden, E. E. O. Ishida, A. G. Kim, M. Klauser, M. Kowalski, M. Kromer, D. K. Küsters, J. Nordin, R. Pain, E. Pecontal, R. Pereira, S. Perlmutter, K. A. Ponder, D. Rabinowitz, M. Rigault, K. Runge, M. Sasdelli, C. Saunders, G. Smadja, N. Suzuki, C. Tao, R. C. Thomas
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
Funders: U.S. Department of Energy, National Aeronautics and Space Administration, Gordon and Betty Moore Foundation, California Institute of Technology, International Max Planck Research School for Environmental, Cellular and Molecular Microbiology, European Commission, Deutsche Forschungsgemeinschaft, Universität Heidelberg, Agence Nationale de la Recherche, National Natural Science Foundation of China, Tsinghua University, Centre National de la Recherche Scientifique, Klaus Tschira Stiftung, International Max Planck Research School for Advanced Methods in Process and Systems Engineering, Office of Science, Jet Propulsion Laboratory, Institut National de Physique Nucléaire et de Physique des Particules, High Energy Physics
OpenAlex ID: W7215119453