Roman Space Telescope to Track Ancient Black Holes via Star-Eating Events

• Tidal Disruption Events (TDEs) occur when a supermassive black hole (SMBH) shreds and consumes a passing star, creating a luminous flare that reveals otherwise invisible black holes.
• Astrophysicists use TDEs to study low-mass SMBHs (100,000 to 100 million solar masses) to understand their growth and origin throughout cosmic history.
• New research published in The Astrophysical Journal models TDE rates, predicting how upcoming missions will provide data on black hole mass functions across cosmic time.

Future Observation Capabilities

• Nancy Grace Roman Space Telescope: Expected to detect ~100 TDEs annually. Its High-Latitude Time Domain Survey (HLTDS) will observe ancient, distant regions, providing clean, well-characterized data crucial for testing growth models.
• Vera Rubin Observatory (LSST): Projected to find tens of thousands of TDEs annually, though its reach is limited in terms of cosmic distance compared to Roman.
• JWST (COSMOS-Web): Will identify TDEs at extremely high redshifts, contributing to the understanding of the earliest stages of the universe.

Implications for SMBH Growth Theories

• TDE observations act as a discriminator between two primary theories for SMBH formation:
  • Light seeds: Massive stars collapse into stellar-mass black holes that merge and accrete mass over time.
  • Heavy seeds: Large SMBHs (up to 1 million solar masses) form directly from the collapse of massive gas clouds.
• Counting TDEs across different redshifts will allow researchers to constrain mass distribution models, such as empirical mass functions versus hydrodynamical simulations like Illustris TNG.