Project

Rationale

Ninety percent of normal matter in the Universe is in gaseous form whereas luminous matter (stars) only account for 10% of the atoms. In ARCTOMO we seek to advance the frontier of knowledge in galaxy evolution by deciphering observationally the role of this diffuse gas in galaxy evolution (a.k.a., the cosmic baryon cycle of galaxies). Specifically, we want to establish for the first time the spatial and kinematical structure of the absorbing circumgalactic medium (CGM) around intermediate-redshift galaxies combining observations from the traditional quasar absorption line technique with those from our novel gravitational-arc tomography.


Giant gravitational arcs can extend over up to a few 100 kpc on the sky at intervening redshifts z~1, thus offering a unique opportunity to probe the CGM of intervening absorbers. In ARCTOMO we work with IFU and echelle observations of some of the brightest arcs known, designed to map the spatial and kinematic distribution of the cool CGM at z~1. These novel observations offer new and independent boundary conditions to models and simulations.

Data

We could not carry out this project without the terrific combination of VLT/MUSE intergal field spectroscopy, HST imaging, and Magellan/MagE spectroscopy.

ESO Very Large Telescope
NASA Hubble Space Telescope
Carnegie Magellan Telescopes