Cosmic acceleration is typically studied by experiments examining the Universe’s expansion history (e.g. from supernovae, baryon acoustic oscillations, the Cosmic Microwave Background, and the Hubble parameter) or the growth of structure (from the abundance of galaxy clusters, weak gravitational lensing, and cosmic velocity fields). The most incisive tests of cosmic acceleration will involve combining measurements using these two complementary approaches. The Joint Analysis Hub will spearhead efforts to bring together the major dark energy/cosmic acceleration experiments and teams to combine datasets in a consistent and powerful way.

South Pole Telescope, SPT
Initially, the Joint Analysis Hub will bring together researchers and data from the South Pole Telescope (SPT) and Dark Energy Survey (DES) projects. Utilizing the Sunyaev Zel’dovich Effect (SZE), the SPT project can identify an unbiased sample of massive galaxy clusters and accurately determine their masses. Optical surveys, such as DES, will detect very large numbers of clusters, including very low mass specimens. Mass estimates for these optically-identified clusters may be obtained via statistical weak lensing studies. A full joint-analysis of the SPT and DES data will combine the raw statistical power and lensing information of the optical data with the redshift independence and tight mass-observable relation of the SZE, providing a uniquely powerful cluster sample for constraining dark energy. Over the longer term, these efforts will expand to include a broader range of researchers and data from proposed surveys such as LSST and DESI. By synthesizing data and expertise from a broad range of experimental efforts, the hub will focus on delivering the next major advance in understanding cosmic acceleration.

Blanco 4m telescope at Chile's Cerro Tololo Inter-American Observatory.
Key to the joint analysis efforts will be complementary theoretical studies. N-body simulations performed by members of the Computational Cosmology MA will be performed to better understand what the observations imply. KICP theorists will actively develop and explore the implications of dark energy and modified gravity models and compare them to the observational data. By engaging a large number of KICP and external researchers investigating cosmic acceleration and focusing their efforts, the Joint Analysis Hub will significantly advance our understanding of this cosmological puzzle.