Summer Program
New Cross-Correlation Perspectives on Cosmic Baryons
August 16–September 13, 2026
Organizers:
Esra Bulbul, Max Planck Institute for Extraterrestrial Physics
Chihway Chang, University of Chicago
Elisabeth Krause, University of Arizona
Vikram Ravi, California Institute of Technology
This workshop will address one of the central open questions in astrophysics and cosmology: how cosmic baryons are distributed around and between galaxies, and how feedback processes shape their physical conditions. By combining complementary probes, we aim to break degeneracies that limit each method individually and build a coherent picture of baryons across a wide halo mass range. Cross-correlation techniques with large-scale structure, weak lensing, X-rays, fast radio burst (FRB) and CMB secondary anisotropies will be a central focus, offering robust tools to characterize feedback physics and its cosmological impact. The three-week program will bring together observers and theorists across these traditionally separate communities to develop a shared modeling framework, identify key cross-correlation observables, and chart a roadmap for exploiting upcoming datasets from SRG/eROSITA, DSA-2000, CHIME/outriggers, CHORD, Rubin LSST, Euclid, Roman, SPT-3G and Simons Observatory. Ultimately, the workshop aims to advance our understanding of baryonic physics, sharpen cosmological constraints, and prepare the community to fully leverage the next generation of surveys.
Summer Workshops
The summer program, running for 16 weeks from late-May to mid-September, emphasizes exciting open problems at the cutting edge. Two or three concurrent workshops, each with a specific focus selected for timeliness and the potential for breakthroughs and of two to five weeks in length, establish the main themes of each week, with twelve or thirteen different workshops each summer, balanced across fields including particle physics, string theory, astrophysics and hard and soft condensed matter physics, as well as emerging areas including biological physics, ultra-cold atom physics, quantum information, and physical mathematics. Additional researchers participate in small working groups or as individual researchers. This framework is designed to maximize informal interactions and free discussion within each area and to promote cross-fertilization between different areas via the common language of theoretical physics. Participation in the summer program of the Aspen Center for Physics is by application and subsequent invitation only. View past workshops.
