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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - A galaxy-driven model of type Ia supernova luminosity variations
AU - Dark Energy Survey Collaboration
AU - Wiseman, P.
AU - Vincenzi, M.
AU - Sullivan, M.
AU - Kelsey, L.
AU - Popovic, B.
AU - Rose, B.
AU - Brout, D.
AU - Davis, T. M.
AU - Frohmaier, C.
AU - Galbany, L.
AU - Lidman, C.
AU - Möller, A.
AU - Scolnic, D.
AU - Smith, M.
AU - Aguena, M.
AU - Allam, S.
AU - Andrade-Oliveira, F.
AU - Annis, J.
AU - Bertin, E.
AU - Bocquet, S.
AU - Brooks, D.
AU - Burke, D. L.
AU - Carnero Rosell, A.
AU - Carrasco Kind, M.
AU - Carretero, J.
AU - Castander, F. J.
AU - Costanzi, M.
AU - Pereira, M. E. S.
AU - Desai, S.
AU - Diehl, H. T.
AU - Doel, P.
AU - Everett, S.
AU - Ferrero, I.
AU - Friedel, D.
AU - Frieman, J.
AU - García-Bellido, J.
AU - Gatti, M.
AU - Gaztanaga, E.
AU - Gruen, D.
AU - Gschwend, J.
AU - Gutierrez, G.
AU - Hinton, S. R.
AU - Hollowood, D. L.
AU - Honscheid, K.
AU - James, D. J.
AU - March, M.
AU - Menanteau, F.
AU - Miquel, R.
AU - Morgan, R.
AU - Palmese, A.
PY - 2022/9/30
Y1 - 2022/9/30
N2 - Type Ia supernovae (SNe Ia) are used as standardizable candles to measure cosmological distances, but differences remain in their corrected luminosities which display a magnitude step as a function of host galaxy properties such as stellar mass and rest-frame U-R colour. Identifying the cause of these steps is key to cosmological analyses and provides insight into SN physics. Here we investigate the effects of SN progenitor ages on their light-curve properties using a galaxy-based forward model that we compare to the Dark Energy Survey 5-yr SN Ia sample. We trace SN Ia progenitors through time and draw their light-curve width parameters from a bimodal distribution according to their age. We find that an intrinsic luminosity difference between SNe of different ages cannot explain the observed trend between step size and SN colour. The data split by stellar mass are better reproduced by following recent work implementing a step in total-to-selective dust extinction ratio (RV) between low- and high-mass hosts, although an additional intrinsic luminosity step is still required to explain the data split by host galaxy U-R. Modelling the RV step as a function of galaxy age provides a better match overall. Additional age versus luminosity steps marginally improve the match to the data, although most of the step is absorbed by the width versus luminosity coefficient α. Furthermore, we find no evidence that α varies with SN age....
AB - Type Ia supernovae (SNe Ia) are used as standardizable candles to measure cosmological distances, but differences remain in their corrected luminosities which display a magnitude step as a function of host galaxy properties such as stellar mass and rest-frame U-R colour. Identifying the cause of these steps is key to cosmological analyses and provides insight into SN physics. Here we investigate the effects of SN progenitor ages on their light-curve properties using a galaxy-based forward model that we compare to the Dark Energy Survey 5-yr SN Ia sample. We trace SN Ia progenitors through time and draw their light-curve width parameters from a bimodal distribution according to their age. We find that an intrinsic luminosity difference between SNe of different ages cannot explain the observed trend between step size and SN colour. The data split by stellar mass are better reproduced by following recent work implementing a step in total-to-selective dust extinction ratio (RV) between low- and high-mass hosts, although an additional intrinsic luminosity step is still required to explain the data split by host galaxy U-R. Modelling the RV step as a function of galaxy age provides a better match overall. Additional age versus luminosity steps marginally improve the match to the data, although most of the step is absorbed by the width versus luminosity coefficient α. Furthermore, we find no evidence that α varies with SN age....
U2 - 10.1093/mnras/stac1984
DO - 10.1093/mnras/stac1984
M3 - Journal article
VL - 515
SP - 4587
EP - 4605
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 3
ER -