Speaker
Description
The observation of highly magnified individual stars at cosmological distances, such as Icarus and Earendel, has opened a new window to study the small-scale distribution of matter within galaxy clusters. Near cluster critical lines, extreme magnification factors make sub-critical dark matter fluctuations (such as axion minihaloes or cold dark matter subhaloes) potentially detectable.
When a background source crosses the corrugated caustic network of a foreground galaxy cluster, the resulting magnification light curve is highly sensitive to the local composition of the lens. This includes both intracluster stars acting as point masses and potential dark matter substructure. In this work, we investigate the distinct phenomenological imprints of extended dark matter perturbations on the light curves of these highly magnified stars, as opposed to the effect of point masses, and use 2D ray-shooting simulations to study simulated lightcurves and investigate possible statistical discriminators.
| Main Contribution topic | Cosmology Dark Matter |
|---|---|
| Secondary contribution topic | Astrophysical observations |