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SAURON: Integral-field Spectroscopy of Galaxies

Miller·Bureau·Verlome·de Zeeuw·Bacon·Copin·Emsellem·Davies·Peletier·Allington-Smith·Carollo·Monnet
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Abstract

We present the first results from a new and unique integral-field spectrograph, SAURON. Based upon the TIGER concept, SAURON uses a lens array to obtain two-dimensional spectroscopy with complete spatial coverage over a field of 33"x41" in low-resolution mode (0.94" lenslets) and of 9"x11" in high-resolution mode (0.26" lenslets). The spectra cover the wavelengths from 4800A to 5400A with a spectral resolution of ~3A (sigma~75 km/s. SAURON achieved first light during commissioning on the William Herschel Telescope on 1 February 1999. We are now commencing a systematic survey of the velocity dispersions, velocity fields, and line-strength distributions of nearby ellipticals and spiral bulges. The wide field of SAURON will be crucial for unraveling complicated velocity structures. In combination with available long-slit spectroscopy of the outer regions of the galaxies, HST spectra of the nuclei, HST imaging, and dynamical modeling, we will constrain the intrinsic shapes, mass-to-light ratios, and stellar populations in spheroids.

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Miller, Bureau, Verlome, de Zeeuw, Bacon, Copin, Emsellem, Davies, Peletier, Allington-Smith, Carollo, Monnet. 1999-06-04. SAURON: Integral-field Spectroscopy of Galaxies. https://arxiv.org/abs/astro-ph/9906091

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