The SDSS/BOSS/eBOSS collaborations were just awarded the 2023 Giuseppe and Vanna Cocconi Prize in cosmology by the High Energy and Particle Physics Division of the European Physical Society.   

The SDSS/BOSS/eBOSS collaborations created the most detailed three-dimensional map of our Universe including data for more than three million galaxies and used the statistical properties of these maps to infer the geometry and structure growth of the universe from a billion years after the Big Bang until today. 

The 2023 Giuseppe and Vanna Cocconi Prize is awarded for outstanding contributions to Particle Astrophysics and Cosmology in the last fifteen years, and in particular, it has been given to the SDSS/BOSS/eBOSS collaborations “for their outstanding contributions to observational cosmology, including the development of the baryon acoustic oscillation measurement into a prime cosmological tool, using it to robustly probe the history of the expansion rate of the Universe back to 1/5th of its age providing crucial information on dark energy, the Hubble constant, and neutrino masses”. 

Baryon acoustic oscillation measurement 

Spectroscopic surveys such as BOSS and eBOSS study the geometry and structure growth in the history of the universe in a model-independent way through the standard ruler technique. This technique uses the galaxy two-point correlation function or its analogue, known as the power spectrum.  

This function quantifies the excess probability of finding two pairs of galaxies at a given distance and encodes the vast majority of the statistical information enclosed in the clustering galaxies, including the signature of a cosmic “standard ruler”.  

The length of the standard ruler can then be directly linked to the so-called sound horizon, which is the distance that any perturbations were able to travel in form of sound waves in the early universe before recombination (which is the epoch were electrons and protons first became bound to form hydrogen atoms). This so called “standard ruler” is also well measured from Cosmic Microwave Background observations.   

By measuring the standard ruler across cosmic time from deep galaxy redshift surveys, the expansion history of the universe can be reconstructed, and this now well-known and standard technique goes under the name of Baryon acoustic oscillations or (BAO). 

Participation of the ICCUB-IEEC 

The Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and the Institute of Space Studies of Catalonia (IEEC) have had an active participation in these collaborations through a number of its researchers, including Héctor Gil-Marín (ICCUB-IEEC), Jordi Miralda (ICCUB-IEEC), Licia Verde (ICREA-ICCUB), Ignasi Pérez-Ràfols (ICCUB-IEEC) and also former members Antonio Cuesta, Beth Reid and Roland de Putter. 

All of this year's prizes from this division of the European Physical Society can be found on the following website.

More information on the BOSS and eBOSS collaborations.