Non-Equilibrium Chemistry & Cooling Alexander Richings & - - PowerPoint PPT Presentation

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Non-Equilibrium Chemistry & Cooling Alexander Richings & Joop Schaye Leiden Observatory Benjamin Oppenheimer University of Colorado 17 th July 2014 I: Chemical Model - Equilibrium Cooling - Non-Equilibrium Cooling II: Simulations -

SLIDE 1

Non-Equilibrium Chemistry & Cooling

Alexander Richings & Joop Schaye Leiden Observatory Benjamin Oppenheimer University of Colorado 17th July 2014

SLIDE 2

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 3

Introduction

Species: ➢ Ions - H, He, N, C, O, Ne, Mg, Si, S, Fe (137 in total) ➢ Molecules - H2, CO & intermediate species (20 in total)

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 4

Species: ➢ Ions - H, He, N, C, O, Ne, Mg, Si, S, Fe (137 in total) ➢ Molecules - H2, CO & intermediate species (20 in total) Cooling: ➢ Metal line cooling ➢ Recombination cooling ➢ Molecular hydrogen ➢ Free-free emission

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

Introduction

SLIDE 5

Species: ➢ Ions - H, He, N, C, O, Ne, Mg, Si, S, Fe (137 in total) ➢ Molecules - H2, CO & intermediate species (20 in total) Cooling: ➢ Metal line cooling ➢ Recombination cooling ➢ Molecular hydrogen ➢ Free-free emission Heating: ➢ Photoheating ➢ Cosmic Rays ➢ Photoelectric dust heating

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

Introduction

SLIDE 6

Equilibrium Cooling

Haardt & Madau (2001) extragalactic UVB; nH = 1 cm-3

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 7

Non-Equilibrium Cooling

Gas cooling isochorically from T = 106 K ➢ Solar metallicity ➢ Haardt & Madau (2001) UV background

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 8

II: Simulations

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 9

Isolated Disc Galaxies

➢ Tree/SPH code Gadget3 (Springel 2005). ➢ Thermal SN feedback (Dalla Vecchia & Schaye 2012). ➢ M200 = 1010 Msol. ➢ mgas = 750 Msol. ➢ Zinit = 0.1 Zsol.

Gas evolution:

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 10

Isolated Disc Galaxies

Non-equilibrium abundances: H2

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary

SLIDE 11

Summary

I: Chemical Model ➢ Important coolants include CII, FeII, SiII, OI & H2. ➢ Recombination lags can enhance the cooling rate below 104 K by up to two orders of magnitude. II: Simulations ➢ We can track gas cooling rates in non-equilibrium.

I: Chemical Model

Equilibrium Cooling
Non-Equilibrium Cooling

II: Simulations

Non-Equilibrium Abundances

Summary