KICP colloquium:  Satya Gontcho A Gontcho (LBNL)

3:30–4:30 pm ERC 161

Satya Gontcho A Gontcho (LBNL) "Status of the Dark Energy Spectroscopic Instrument"

The Dark Energy Spectroscopic Instrument (DESI) is a robotic, fiber-fed spectroscopic surveyor mounted on the Mayall 4-meter telescope at Kitt Peak National Observatory. It can obtain spectra of almost 5000 objects over approximately 7.5 square degrees of sky in a single visit. On May 14, 2021, DESI embarked on a five-years survey of more than 30 million extragalactic sources over 14,000 square degrees. This 3D map of galaxies and quasars will be used to produce precise new constraints on the expansion history of the Universe up to a redshift of 3.5 and will measure the growth rate of structure in the redshift range 0.7-1.6 with unequaled precision (<1.5% per redshift bin of 0.1).  The start of the survey marks the end of a successful survey validation period during which more than one million cosmological redshifts were measured. This data set, along with many commissioning studies, has demonstrated that the DESI project meets its science requirements written many years ago. I will give an overview of the performance of DESI since we have been on sky and touch on the exciting science we are looking forward to doing over the next few years.

Event Type


Nov 17