Julien Guy (LBNL) "The DESI Project, Construction Status and Prospects for Precise Cosmological Distance Measurements with Lyman-Alpha Forests"

Abstract:
The Dark Energy Spectroscopic Instrument is a multi-object spectrograph composed of a wide field corrector, a 5000 robotically positioned fiber system, and 10 3-arms spectrographs. The instrument is installed this year on the Mayall 4-m diameter telescope at Kitt Peak, Arizona. Operations will start next year. In 5 years, DESI will measure spectra and redshifts of more than 30 million galaxies and quasars. This catalog will be used to measure the expansion history of the Universe and the growth rate of structure in the past 10 billion years with sub-percent precision. I will present the construction status and give some insight on the Lyman-alpha BAO analysis.