Space & astronomy · the experiment
Weigh the black hole of MoM-BL-z10
A black hole seen 470 million years after the Big Bang, a broadened hydrogen line at 5.35 µm. Four questions, from beginner to expert, to check what that line can tell.
1 · Find the scales
Beginner
How did the team estimate the black hole's mass?
2 · Push it to the limit
With the standard recipe, the black hole feeds at 11% of the Eddington limit: its luminosity is 0.11 times the maximum its mass allows.
Intermediate
At the same mass, if it fed at the limit, its luminosity would be multiplied by about…
3 · Grow two seeds
To reach 36 million solar masses, a stellar seed of 100 solar masses must grow by a factor of 360,000; a heavy seed of 100,000, by a factor of 360. Both start at the same time, and a feeding black hole grows exponentially.
Expert
Compared with the heavy seed, how fast must the stellar seed feed?
4 · Narrow the line
The broad line measures 3,480 km/s, with a margin of −950 to +2,040 km/s. In a virial mass, the mass is proportional to the square of the gas speed.
Expert
If the true width sat at its lower bound, 2,530 km/s, what would become of the mass of 36 million solar masses?
Black hole weighed
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