The Cosmic Evolution Survey (COSMOS) is an astronomical survey designed to probe the formation and evolution of galaxies as a function of both cosmic time (redshift) and the local galaxy environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes and a number of large ground based telescopes, with many ongoing surveys. Over 2 million galaxies are detected, spanning 75% of the age of the Universe. The COSMOS is led by Peter Capak and involves more than 200 scientists in a dozen countries and information on the science steering committee can be found here.
Galaxies in the early Universe (< 2 billion years after the Big Bang or <10% of the current age of the Universe) experience a rapid growth in stellar mass. This goes along with a rapid evolution of their inter-stellar medium properties and physical structure. The mechanisms and physics that lead to this short early growth phase are mostly unknown. We got 70h on the Atacama Large (Sub-) Millimeter Array (ALMA) to study the gas and dust properties of young galaxies during the early growth phase to address these questions.
The graphic shows increase in the cosmic stellar mass density as a function of time and redshift. The increase is particularly steep during the first 2 billion years after the Big Bang going a long with substantial transformation of the galaxies' inter-stellar medium and physical structure. ALPINE will probe the gas and dust properties of galaxies in that early growth phase on statistically large samples and help us to understand the physical mechanisms behind it.
Greetings from Manchester! Several COSMOS team members are here at the UK ARC node ALMA regional centre this week attending the 'Measuring Star Formation in the Radio, Millimetre and Submillimetre' workshop. We're asking questions like: What is the best way to measure star formation in galaxies? What are the biases involved in our measurements and how can we overcome them? What kind of observations and telescopes do we need in the future to achieve this? We're already well on the way with amazing telescopes like ALMA, JVLA and Herschel and we look forward to the future with JWST, SKA and beyond!
Picture: Left to right - Daniel Molnar (Uni. Sussex), Eric Jimenez-Andrade (Uni. Bonn), Sarah Leslie (MPIA), Jacinta Delhaize (Uni. Zagreb), Kevin Harrington (Uni. Bonn). At the UK ARC Node ALMA Regional Centre.