81 lines
2.0 KiB
Typst
81 lines
2.0 KiB
Typst
#import "importer/main.typ": *
|
||
#import "@preview/physica:0.9.5": *
|
||
#import "@preview/touying:0.6.1": *
|
||
|
||
|
||
= Simulating the Epoch of Reionization
|
||
== The Epoch of Reionization
|
||
- Marks the universe’s last major phase transition: from neutral to ionized hydrogen.
|
||
|
||
- Shapes the large-scale structure of the intergalactic medium (IGM).
|
||
|
||
- Is strongly linked to the formation and growth of the first galaxies and black holes.
|
||
|
||
- Sets the stage for many observables: CMB secondary anisotropies, 21-cm signal, high-z galaxy surveys.
|
||
// reformulate
|
||
|
||
== The 21cm signal
|
||
|
||
The brigthtness temperature describes the difference between the CMB temperature and the spin temperature of neutral hydrogen
|
||
#grid[
|
||
#image("assets/cmb_black_body_spectrum.svg", height: 1fr, fit: "contain") @cmb_spectrum
|
||
][
|
||
Removing the contribution from the black body spectrum of the CMB yields the explicit 21-cm signal:
|
||
#image("assets/cmb_black_body_spectrum.svg", height: 1fr, fit: "contain")
|
||
|
||
]
|
||
|
||
|
||
|
||
#align(center)[
|
||
#image("assets/evolution_of_dtb.png", fit: "contain")
|
||
]
|
||
@Pritchard2012
|
||
|
||
#pagebreak()
|
||
|
||
$
|
||
d T_"b" (bold(x), z) tilde.eq T_0 (z) dot x_"HI" (bold(x), z) dot (1 + delta_b (bold(x), z)) dot (x_alpha (bold(x), z)) / (1 + x_alpha (bold(x), z) ) dot ((1 - T_"CMB" (z)) / (T_"gas" (bold(x), z)))
|
||
$ <eq:dTb>
|
||
(e.g @Pritchard2012)
|
||
|
||
|
||
|
||
== The halo model of reionization
|
||
|
||
|
||
|
||
Following @Schneider_2021 @schneider2023cosmologicalforecast21cmpower:
|
||
|
||
$
|
||
rho_alpha (r bar M, z) = (1 + z)^2 / (4 pi r^2) dot sum_(n=2)^(n_m)f_n dot epsilon_alpha (nu prime) dot f_star dot dot(M)(z prime bar M, z)
|
||
$
|
||
#line(
|
||
length: 100%
|
||
)
|
||
$
|
||
3/2 dot derivative(rho_h (r bar M, z), z) = (3 rho_h (r bar M, z)) / (1 + z) - (rho_"xray" (r bar M, z)) /(k_B (1 + z) H(z))
|
||
$
|
||
#line(
|
||
length: 100%
|
||
)
|
||
$
|
||
x_("HII")(r bar M, z) = theta_"H" lr([R_b (M, z) - r], size: #150%)
|
||
$
|
||
|
||
|
||
|
||
== The current state of simulations
|
||
#lorem(20)
|
||
|
||
- slow and big
|
||
- radiative transfer // what are the downsides
|
||
|
||
|
||
$==>$ semi-numerical approaches such as `BEoRN` @Schaeffer_2023
|
||
|
||
|
||
#link(<backup_validation>, "validation")
|
||
|
||
== `BEoRN`
|