Apr 222013

The dust is settling after last week’s whirlwind of talks and discussions at the Cluster Lensing Workshop and our half day seminar on the Frontier Fields.   We’ve learned a lot about the exciting work going on in the lensing community.    It is particularly exciting to hear about the plans people have for the Frontier Fields.   Not surprisingly,  people are anticipating science beyond the original goals set out by the HDFI science working group.

There were many great talks…  here are just a few  highlights –

Johan Richard talked about using the new panoramic integral-field spectrograph “MUSE” at the VLT to obtain spectroscopy of the lensed galaxies in the Frontier Fields.

Maruša Bradac gave an overview of the Spitzer UltRa Faint SUrvey (SURF’s Up) to obtain very deep Spitzer observations of 10 clusters (including some FF clusters).

Priya Natarajan and Zoltan Haiman both presented (different) ideas about how the Frontier Fields may help constrain the nature of dark matter and dark energy.

Priya talked about how multiple images of lensed galaxies at different redshifts depended upon the distances to those objects, and therefore could be used constrain the matter density of the universe Ωm and the dark energy equation of state w.   From Priya’s slides:



Zoltan and Priya both talked about how the Frontier Fields would provide probes of the nature of dark matter.   If dark matter is warm,  then small dark matter halos cannot form.   The mass of the dark matter particle can be constrained by measuring either the distribution of “substructure” (low mass halos) in the Frontier Fields clusters themselves,  or by counting the number of lensed galaxies living in low mass halos at very high redshift (z~10).  The detection of two good z~10 galaxy candidates from the CLASH survey already imply a lower limit for the warm dark matter mass >~ 1 keV.   From Zoltan’s slides: