The JWST discovery of a number of super-early (redshift z > 10) blue galaxies requires these systems to be essentially dust free in spite of their large stellar masses. A possible explanation is that dust is evacuated by radiatively driven outflows. We test this hypothesis by deriving the Eddington ratio lambda(E) = L-bol/L-E, where L-bol is the bolometric luminosity produced by star formation and possible black hole accretion, for 134 galaxies at 6.5 < z < 16. We find a strong anticorrelation between lambda(E) and dust UV optical depth, tau(1500) infinity lambda(-0.63)(E) also, lambda(E) increases with redshift. We confirm that galaxies exceeding a specific star formation rate sSFR > 13 Gyr(-1 )develop powerful outflows clearing the galaxy from its dust. This result is supported by ALMA dust continuum nondetections in three super-early systems.
Dusty-wind-clear JWST Super-early Galaxies
Manuela Bischetti;
2023-01-01
Abstract
The JWST discovery of a number of super-early (redshift z > 10) blue galaxies requires these systems to be essentially dust free in spite of their large stellar masses. A possible explanation is that dust is evacuated by radiatively driven outflows. We test this hypothesis by deriving the Eddington ratio lambda(E) = L-bol/L-E, where L-bol is the bolometric luminosity produced by star formation and possible black hole accretion, for 134 galaxies at 6.5 < z < 16. We find a strong anticorrelation between lambda(E) and dust UV optical depth, tau(1500) infinity lambda(-0.63)(E) also, lambda(E) increases with redshift. We confirm that galaxies exceeding a specific star formation rate sSFR > 13 Gyr(-1 )develop powerful outflows clearing the galaxy from its dust. This result is supported by ALMA dust continuum nondetections in three super-early systems.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
