Argument by contradiction

~75%

~40%

1e42

Fraction obscured

Accretion Luminosity [erg/s]

20%

From low-M

No low-M

• Bright: high-M
• Faint: low-M & high-M
• Low-M: 20% f(obsc)
• H0: Galaxy-scale gas is obscurer
• Either:
• high-M have more obscuration
• high-M have less obscuration
• Drop of 35% can not be explained → reject H0