BLACK HOLES ARCHAEOLOGY WITH THE COSMIC ARCHAEOLOGY TOOL
The formation and growth of the first supermassive black holes.
One of the biggest challenges in modern astrophysics is understanding how supermassive black holes (SMBHs), with masses between 109−1010 M⊙ formed less than a billion years after the Big Bang (z>6).
The CAT project aims to investigate:
✅ The nature of the initial black hole (BH) seeds—whether they were light, intermediate, or heavy—and how they grew into SMBHs
✅ The observational signatures of these seeds in both electromagnetic (EM) and gravitational wave (GW) signals
✅ The properties of the black hole population at cosmic dawn
The project is designed to study the evolution of the first black holes in distant galaxies, beginning with the formation of the first stars and following their development over cosmic time. Along this evolutionary path, we model both the electromagnetic emission from active galactic nuclei (AGN) and the gravitational wave signals generated by merging binary black holes. Our models are tightly connected to observations. On one hand, we use observational data to calibrate free parameters in our simulations. On the other, our predictions are used to interpret current observations, optimize observing strategies, and define science goals for future telescopes and instruments.
Project goals
📌 How did the first black holes form and grow?
- Investigating different seed formation channels and accretion regimes (Eddington-limited vs. super-Eddington)
- Identifying their impact on the AGN mass and luminosity functions over cosmic time.
📌What role do black hole mergers play?
- Exploring the contribution of binary BH populations, formed after galaxy mergers, to SMBH growth at z>6
- Predicting merger rates for LISA and Einstein Telescope.
- Investigating whether multi-frequency GW detections can reveal the origins of black holes
📌 How can we identify the first AGN?
- Developing new observational strategies and diagnostic tools to detect early AGN.
- Overcoming the limitations of traditional methods at high redshift.
The CAT Model: A New Approach to High-Redshift SMBH Growth
To answer these questions, we are developing CAT, an advanced theoretical model specifically designed to study the early Universe.
🔬 What makes CAT unique?
- It provides a self-consistent, environment-dependent description of the formation of the first stars and black holes.
- It resolves the smallest dark matter halos (z∼20−30), where the first stars formed.
- It complements numerical/hydrodynamical simulations, offering a fast and efficient tool to explore extreme cosmic conditions.
Bridging Theory and Observations
CAT is more than a model—it’s a key tool for interpreting observations from the world’s most advanced telescopes.
We work in collaboration with scientists involved in current and future missions, including:
🛰️ The James Webb Space Telescopes
🔹 Deep infrared surveys
🛰️Athena, Lynx, AXIS
🔹X-ray studies
🌍 Ground-Based Observatories
🔹 MOONS (VLT) – Spectroscopic galaxy surveys
🔹 Einstein Telescope (ET) – Gravitational wave detection
🔭 Future Missions
🔹 LISA – Detecting GW signals from BH mergers
🔹 Euclid – Exploring dark matter and galaxy evolution
Our ultimate goal? To build a comprehensive cosmological framework explaining the evolution of AGN, from dormant SMBHs to the bright quasars observed at z>6
📢 Want to learn more? Stay tuned for updates on our latest discoveries in the early Universe! 🔗
contact: rosa.valiante@inaf.it