SITELLE: An Imaging Fourier Transform Spectrometer for the Canada-France-Hawaii Telescope

Laurent Drissen; Thomas Martin; Laurie Rousseau-Nepton; Carmelle Robert; R. Pierre Martin; Marc Baril; Simon Prunet; Gilles Joncas; Simon Thibault; Denis Brousseau; Julie Mandar; Frédéric Grandmont; Howard Yee; Luc Simard

doi:10.1093/mnras/stz627

arXiv · 1811.06644

SITELLE: An Imaging Fourier Transform Spectrometer for the Canada-France-Hawaii Telescope

Laurent Drissen·Thomas Martin·Laurie Rousseau-Nepton·Carmelle Robert·R. Pierre Martin·Marc Baril·Simon Prunet·Gilles Joncas·Simon Thibault·Denis Brousseau·Julie Mandar·Frédéric Grandmont·Howard Yee·Luc Simard

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Abstract

We present an overview of SITELLE, an Imaging Fourier Transform Spectrometer (iFTS) available at the 3.6-meter Canada-France-Hawaii Telescope. SITELLE is a Michelson-type interferometer able to reconstruct the spectrum of every light source within its 11' field of view in filter-selected bands of the visible (350 to 900 nm). The spectral resolution can be adjusted up to R = 10 000 and the spatial resolution is seeing-limited and sampled at 0.32 arcsec per pixel. We describe the design of the instrument as well as the data reduction and analysis process. To illustrate SITELLE's capabilities, we present some of the data obtained during and since the August 2015 commissioning run. In particular, we demonstrate its ability to separate the components of the [OII] $\lambda\lambda$ 3726,29 doublet in Orion and to reach R = 9500 around H-alpha; to detect diffuse emission at a level of 4 x 10e-17 erg/cm2/s/arcsec2; to obtain integrated spectra of stellar absorption lines in galaxies despite the well-known multiplex disadvantage of the iFTS; and to detect emission-line galaxies at different redshifts.

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Laurent Drissen, Thomas Martin, Laurie Rousseau-Nepton, Carmelle Robert, R. Pierre Martin, Marc Baril, Simon Prunet, Gilles Joncas, Simon Thibault, Denis Brousseau, Julie Mandar, Frédéric Grandmont, Howard Yee, Luc Simard. 2018-11-16. SITELLE: An Imaging Fourier Transform Spectrometer for the Canada-France-Hawaii Telescope. https://doi.org/10.1093/mnras/stz627

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