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master-thesis-presentation/introduction.typ
2025-09-17 01:02:10 +02:00

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#import "globals.typ": *
= Simulating the Epoch of Reionization
== The Epoch of Reionization
- Marks the universes 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 21-cm signal
The brigthtness temperature describes the difference between the CMB temperature and the spin temperature of neutral hydrogen
#v(1em)
#grid(columns: 2, align: center)[
#image("assets/cmb_black_body_spectrum.svg", height: 1fr, fit: "contain") #text(size: 0.8em)[from @cmb_spectrum]
][
#pause
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")
]
#pagebreak()
#align(center)[
#image("assets/evolution_of_dtb.png", height: 85%, fit: "contain")
#text(size: 0.8em)[from @Pritchard2012]
]
== Expression the 21-cm signal
Expressing the _differential brightness temperature_ (e.g @Pritchard2012):
$
d T_"b" (bold(x), z) tilde.eq T_0 (z) dot
#pin(1) x_"HI" (bold(x), z) #pin(2) dot
(1 + delta_b (bold(x), z)) dot
(x_alpha (bold(x), z)) / (#pin(3) 1 + x_alpha (bold(x), z) #pin(4) ) dot
((1 - T_"CMB" (z)) / (#pin(5) T_"gas" (bold(x), z) #pin(6)))
$ <eq:dTb>
// Explanation
- further modulation by _RSD_
== The current state of simulations
#layouts.contained(
[
*Traditional approaches*
// keypoints that describe heavy hydro + radiative transfer simulations
- require hydrodynamics
- require radiative transfer
- scale poorly
$=>$ no reproducibility
#pause
],
[
#text(weight: "bold")[semi-numerical approaches]
such as #beorn @Schaeffer_2023, `21cmFAST` [CITATION]
- approximative treatment
- link
- scalable + efficient
$=>$ reproducible and flexible
]
)
// #layouts.two-boxes(
// [
// #text(weight: "bold")[Traditional approaches]
// // keypoints that describe heavy hydro + radiative transfer simulations
// - require hydrodynamics
// - require radiative transfer
// - scale poorly
// $=>$ no reproducibility
// #pause
// ],
// [
// *semi-numerical approaches*
// such as #beorn @Schaeffer_2023, `21cmFAST` [CITATION]
// - approximative treatment
// - link
// - scalable + efficient
// $=>$ reproducible and flexible
// ]
// )
#pagebreak()
== Matrix
#layouts.matrix((
brand.wordmark,
brand.wordmark,
brand.wordmark,
brand.wordmark,
brand.wordmark,
brand.wordmark
))
== Contained
#layouts.contained(
columns(2, [
- #lorem(10)
- #lorem(15)
- #lorem(25)
]),
brand.wordmark
)
== Four columns
#layouts.four-columns(
[
#text(weight: "bold", brand.wordmark)
#v(1em)
#text(size: 10.5pt)[#lorem(60)]
],
[
#text(weight: "bold", brand.wordmark)
#v(1em)
#text(size: 10.5pt)[#lorem(45)]
],
[
#text(weight: "bold", brand.wordmark)
#v(1em)
#text(size: 10.5pt)[#lorem(75)]
],
[
#text(weight: "bold", brand.wordmark)
#v(1em)
#text(size: 10.5pt)[#lorem(50)]
]
)
== Two columns
#layouts.contained(
columns(2, [
- #lorem(10)
- #lorem(15)
- #lorem(25)
]),
brand.wordmark
)