Chronos: A NIR spectroscopic survey to target the most important phases of galaxy evolution across cosmic time

I. Ferreras; M. Cropper; R. Sharples; J. Bland-Hawthorn; G. Bruzual; S. Charlot; C. J. Conselice; S. Driver; J. Dunlop; A. M. Hopkins; S. Kaviraj; T. Kitching; F. La Barbera; O. Lahav; A. Pasquali; S. Serjeant; J. Silk; R. Windhorst

doi:10.1007/s10686-021-09702-2

arXiv · 1908.08795

Chronos: A NIR spectroscopic survey to target the most important phases of galaxy evolution across cosmic time

I. Ferreras·M. Cropper·R. Sharples·J. Bland-Hawthorn·G. Bruzual·S. Charlot·C. J. Conselice·S. Driver·J. Dunlop·A. M. Hopkins·S. Kaviraj·T. Kitching·F. La Barbera·O. Lahav·A. Pasquali·S. Serjeant·J. Silk·R. Windhorst

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Abstract

(Abridged summary) Responding to ESA's Voyage 2050 call to define the long-term plan for the future space missions that will address the astrophysics science questions during the 2035-2050 cycle, we propose a dedicated, ultra-deep spectroscopic survey in the near infrared (NIR), that will target a mass-limited sample of galaxies during two of the most fundamental epochs of cosmic evolution: the formation of the first galaxies (at z>6; cosmic dawn), and at the peak of galaxy formation activity (between redshift z=1 and 3; cosmic noon). By way of NIR observations, it is possible to study the Lyman-alpha region in the former, and the optical rest-frame in the latter, allowing us to extract fundamental observables such as gas and stellar kinematics, chemical abundances, and ages, providing a unique legacy database covering these two crucial stages of cosmic evolution. A dedicated, space-based facility will overcome the challenges faced by ground-based telescopes, no matter how large the aperture, or the reduced field of view and low multiplex factor of the best space-based instrument in the near future, namely NIRSpec at the JWST. Our project (codename Chronos) aims to produce about 1 million high quality spectra, with a high S/N in the continuum, where information about the underlying stellar populations is encoded.

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I. Ferreras, M. Cropper, R. Sharples, J. Bland-Hawthorn, G. Bruzual, S. Charlot, C. J. Conselice, S. Driver, J. Dunlop, A. M. Hopkins, S. Kaviraj, T. Kitching, F. La Barbera, O. Lahav, A. Pasquali, S. Serjeant, J. Silk, R. Windhorst. 2019-08-22. Chronos: A NIR spectroscopic survey to target the most important phases of galaxy evolution across cosmic time. https://doi.org/10.1007/s10686-021-09702-2

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