Maximizing the science return of SITELLE with applications to the evolution of galaxies near and far

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Over the past decade, my team has developped, in collaboration with the Québec City-based company ABB, a novel type of imaging spectrometers for visible-light astronomy, Imaging Fourier Transform Spectrometers (iFTS). After having worked on SpIOMM, a prototype IFTS attached to the 1.6-m telescope of the Observatoire du Mont Mégantic, this work will culminate in 2014 with the commissioning of SITELLE as a guest instrument at the Canada-France-Hawaii Telescope; it will be available to the entire CFHT community in the summer of 2014. SITELLE is an iFTS designed to obtain a spectrum for every pixel (0.32'') in a 11' x 11' field of view, in selected bandpasses of the visible band (350 - 900 nm), with a spectral resolution varying between R = 10 and 20 000. This instrument will be used to determine the physical characteristics of comets, nebulae in the Milky Way, nearby galaxies, as well as to characterize the star-formation rate in the more distant Universe. In this proposal, I present a plan to optimize the science return of SITELLE, and use it to study the process of star formation and chemical evolution in galaxies.I see it as a prime objective of my work in the next five years to make sure that SITELLE is used at its full potential by a large fraction of the CFHT community. Continuous support for SITELLE and its users is of prime importance for the success of this instrument, especially given its non-conventional approach to hyperspectral imagery. Data simulation, acquisition, processing and post-processing softwares are now being developped and tested on SpIOMM and simulated SITELLE data cubes; they will however need to be tested on real SITELLE data, and constantly updated throughout the lifetime of the instrument in order to maximize its scientific output. I will also use SITELLE for three projects that oriented its design from the beginning and emphasize its full potential: - The Survey for Nebular Abundances in Galaxies with SITELLE (SNAGS) is mostly aimed at determining the abundance distribution in the disks of several dozen nearby galaxies. I intend to take advantage of SITELLE's high resolution (seeing-limited) to concentrate on evidences of local fluctuations related to the presence of massive stars and their effect on their surrounding ISM, in particular nitrogen enrichement, ionization and kinematics. SITELLE data will be supplemented with long-slit spectra from 8-m class telescopes, archival HST & Galex and UVIT data. - In collaboration with Iglesias (IAA, Spain) and Plana (LATO - Brazil), I will observe with SpIOMM and SITELLE a sample of low-redshift (z < 0.1) compact groups of galaxies, all of them with clear signs of interactions, in order to understand the phenomena at play in such groups, and in particular star formation in the tidal tails. Measurements of the most conspicuous emission lines will allow us to study the properties (density, metallicity, excitation, kinematics) of the ionized gas, and thus of the young stellar populations not only in the main bodies of the galaxies, but also in the tidal features associated to the interactions thoughout the virial region of the group. - SITELLE is an ideal instrument to detect, with relatively low biases, very distant star-forming galaxies through their [OII] (up to z ~ 1) or Lya (z ~ 2 - 5) emission. In collaboration with Simard (NRC) and Willis (Uvic) I will use SITELLE to undergo a deep survey for emission-line galaxies in a wide cosmological volume in order to study the star-formation process at different redshifts.