We present the HOLISMOKES programme on strong gravitational lensing of supernovae (SNe) as a probe of SN physics and cosmology. We investigate the effects of microlensing on early-phase SN Ia spectra using four different SN explosion models. We find that distortions of SN Ia spectra due to microlensing are typically negligible within ten rest-frame days after a SN explosion (< 1% distortion within the 1σ spread and ≲ 10% distortion within the 2σ spread). This shows the great prospects of using lensed SNe Ia to obtain intrinsic early-phase SN spectra for deciphering SN Ia progenitors. As a demonstration of the usefulness of lensed SNe Ia for cosmology, we simulate a sample of mock lensed SN Ia systems that are expected to have accurate and precise time-delay measurements in the era of the Rubin Observatory Legacy Survey of Space and Time (LSST). Adopting realistic yet conservative uncertainties on their time-delay distances and lens angular diameter distances, of 6.6% and 5%, respectively, we find that a sample of 20 lensed SNe Ia would allow us to constrain the Hubble constant (H0) with 1.3% uncertainty in the flat ΛCDM cosmology. We find a similar constraint on H0 in an open ΛCDM cosmology, while the constraint degrades to 3% in a flat wCDM cosmology. We anticipate lensed SNe to be an independent and powerful probe of SN physics and cosmology in the upcoming LSST era.
Bibliographical noteFunding Information:
Acknowledgements. We thank M. Oguri and P. Marshall for the useful lens catalog from Oguri & Marshall (2010), E. Komatsu, S. Jha and S. Rodney for helpful discussions, and the anonymous referee for the constructive comments. S.H.S. thanks M. Barnabè for the animated discussion in conjuring up the programme acronym. S.H.S., R.C., S.S. and A.Y. thank the Max Planck Society for support through the Max Planck Research Group for S.H.S. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (LENSNOVA: grant agreement No 771776; COSMICLENS: Grant agreement No. 787886). This research is supported in part by the Excellence Cluster ORIGINS which is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence Strategy – EXC-2094 – 390783311. This work is supported by the Swiss National Science Foundation (SNSF).
© S. H. Suyu et al. 2020.
Copyright 2020 Elsevier B.V., All rights reserved.
- Cosmological parameters
- Galaxies: distances and redshifts
- Galaxies: kinematics and dynamics
- Gravitational lensing: micro
- Gravitational lensing: Strong
- Supernovae: general
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science