Gregory's Serverhey yall, here's a #science thread!
One of the larger excitements of my past couple months is finally getting this paper out -- it's up on arXiv tonight and accepted to ApJL (with an AAS Nova highlight on the way)
This paper is trying to answer the question of how many really big black holes are in our corner of the universe and the consequence of that number.
We think that our work substantially refines the census of black holes more than about a billion times the mass of the sun, which places constraints on the evolution of massive galaxies over the past couple billion years and furthers our understanding of the cosmic gravitational wave background
In this thread I'll tell ya how we did it! Let's dive in!
Read the paper here: https://arxiv.org/abs/2407.14595
1/8
hey yall, here's a #science thread!
One of the larger excitements of my past couple months is finally getting this paper out -- it's up on arXiv tonight and accepted to ApJL (with an AAS Nova highlight on the way)
This paper is trying to answer the question of how many really big black holes are in our corner of the universe and the consequence of that number.
An important discovery in the past quarter century or so of extragalactic astronomy is the existence of scaling relations which very simply relate different properties of those galaxies.
One of the most intriguing relations connects the total stellar mass of a galaxy to the mass of its black hole. Virtually every evolved galaxy in the sky has a supermassive black hole in its center, and the mass of each of those black holes is about 0.2% the mass of the stars in its galaxy.
At first glance, this relation is pretty simple -- big galaxies have big black holes. But more profoundly this relation suggests that supermassive black holes co-evolve with the galaxies they live in.
This winds up begin a really useful tool: If you know the mass of all the stars in a galaxy, you can reasonably estimate the mass of its black hole! So if we want to build a census of black holes, we can start out with a census of galaxy stellar masses!
2/8
An important discovery in the past quarter century or so of extragalactic astronomy is the existence of scaling relations which very simply relate different properties of those galaxies.
One of the most intriguing relations connects the total stellar mass of a galaxy to the mass of its black hole. Virtually every evolved galaxy in the sky has a supermassive black hole in its center, and the mass of each of those black holes is about 0.2% the mass of the stars in its galaxy.
@erl fascinating thread, thank you!
(this is a bit of a boring question, but what do astrophysicists make their plots with?)