The Dark Energy Survey Supernova Program: slow supernovae show cosmological time dilation out to z ~ 1.
ABSTRACT We present a precise measurement of cosmological time dilation using the light curves of 1504 Type Ia supernovae from the Dark Energy Survey spanning a redshift range $$0.1\lesssim z\lesssim 1.2$$. We find that the width of supernova light curves is proportional to $(1+z)$, as expected for time dilation due to the expansion of the Universe. Assuming Type Ia supernovae light curves are emitted with a consistent duration $$\Delta t_{\rm em}$$, and parametrizing the observed duration as $$\Delta t_{\rm obs}=\Delta t_{\rm em}(1+z)^b$$, we fit for the form of time dilation using two methods. First, we find that a power of $$b \approx 1$$ minimizes the flux scatter in stacked subsamples of light curves across different redshifts. Secondly, we fit each target supernova to a stacked light curve (stacking all supernovae with observed bandpasses matching that of the target light curve) and find $$b=1.003\pm 0.005$$ (stat) $$\pm \, 0.010$$ (sys). Thanks to the large number of supernovae and large redshift-range of the sample, this analysis gives the most precise measurement of cosmological time dilation to date, ruling out any non-time-dilating cosmological models at very high significance.
- Research Organization:
- ARC, Canberra; Australian Astron. Observ.; Australian Natl. U., Canberra; Australian Natl. U., Canberra (main); Barcelona, Autonoma U.; Barcelona, IEEC; Barcelona, IFAE; Caltech, JPL; Carnegie Mellon U.; Cerro-Tololo InterAmerican Obs.; Chicago U., Astron. Astrophys. Ctr.; Chicago U., EFI; Chicago U., KICP; Duke U.; Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Hamburg Observ.; Harvard-Smithsonian Ctr. Astrophys.; IAC, La Laguna; ICREA, Barcelona; Illinois U., Urbana (main); Illinois U., Urbana, Astron. Dept.; Indian Inst. Tech., Hyderabad; LIneA, Rio de Janeiro; LPSC, Grenoble; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Lowell Observ.; Madrid U.; Madrid, CIEMAT; Madrid, IFT; Munich U.; Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Ohio State U.; Ohio State U., CCAPP; Oslo U.; Pennsylvania U.; Portsmouth U., ICG; Princeton U., Astrophys. Sci. Dept.; Queensland U.; Rio de Janeiro Observ.; SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Sao Paulo U., Sao Carlos; Southampton U.; Sussex U., Astron. Ctr.; Swinburne U. Tech., Hawthorn; Sydney U.; Texas A-M; Trieste Observ.; U. Michigan, Ann Arbor; UC, Berkeley, Astron. Dept.; UC, Santa Cruz; University Coll. London
- Sponsoring Organization:
- US Department of Energy; USDOE
- Grant/Contract Number:
- 89243024CSC000002; AC02-07CH11359
- OSTI ID:
- 2439655
- Report Number(s):
- DES-2024-0831; FERMILAB-PUB-24-0293-PPD
- Journal Information:
- Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 3 Vol. 533; ISSN 0035-8711
- Publisher:
- Oxford University PressCopyright Statement
- Country of Publication:
- United Kingdom
- Language:
- English
Similar Records
PHOTOMETRIC ESTIMATES OF REDSHIFTS AND DISTANCE MODULI FOR TYPE Ia SUPERNOVAE
Carnegie Supernova Project-II: Extending the Near-infrared Hubble Diagram for Type Ia Supernovae to z ~0.1