# Calibrating the standard candles with strong lensing

## TL;DR

This paper introduces a model-independent method using strong lensing observations to calibrate Type Ia supernova distances, improving the accuracy of intrinsic property measurements like absolute magnitude.

## Contribution

It presents a novel approach leveraging future strong lensing data to calibrate supernovae without relying on cosmological models, enhancing distance measurement precision.

## Key findings

- Calibrated the supernova absolute magnitude with ~0.24 mag uncertainty using angular diameter distances.
- Achieved ~0.03 mag uncertainty in calibration with time delay distances.
- Demonstrated the method's robustness even with evolving distance relations such as cosmic opacity.

## Abstract

We propose a new model-independent strategy to calibrate the distance relation in Type Ia supernova (SN) observations and to probe the intrinsic properties of SNe Ia, especially the absolute magnitude $M_B$, basing on strong lensing observations in the upcoming Large Synoptic Survey Telescope (LSST) era. The strongly lensed quasars can provide the Time Delay Distances (TDD) and the Angular Diameter Distances (ADD) to the lens galaxies. These absolute distance measurements can model-independently anchor the SNe Ia at cosmological distances. We simulated 55 high-quality lensing systems with $5\%$ uncertainties for both TDD and ADD measurements basing on future observation conditions. For the time delay distances and the angular diameter distances as the calibration standards, the calibrated $1\sigma$ uncertainties of $M_{B}$ are approximately 0.24 mag and 0.03 mag, respectively. Besides, we also consider an evolving distance relation, for example, caused by the cosmic opacity. In this case, the $1\sigma$ uncertainties of $M_B$ calibrated with TDD and ADD are approximately 0.31 mag and 0.06 mag, respectively. The results show that the ADD method will be a promising tool for calibrating supernovae.