Nucleosynthetic signatures of primordial origin around supermassive black holes

Understand

If primordial black holes (PBHs) seeded the supermassive black holes (SMBHs) at the centers of high-redshift quasars, then the gas surrounding these black holes may reveal nucleosynthetic clues to their primordial origins.

• We present predictions of altered primordial abundances around PBHs massive enough to seed SMBHs at z~6-7.5.
• We find that if PBHs with initial masses of ~10^5 M$_{\odot}$ are responsible for such SMBHs, they may produce primordial Deuterium and Helium fractions enhanced by >~ 10%, and Lithium abundance depleted by >~10%, at distances of up to ~ a comoving kiloparsec away from the black hole after decoupling.
• We estimate that ~ 10^8 M$_{\odot}$ of gas is enhanced (or depleted) by at least one percent.