Download presentation
Presentation is loading. Please wait.
1
Modeling Cosmic Reionization (Leave No Photon Behind) Nick Gnedin
2
Co-starring Gayler Harford
3
Balancing the Books (Bunker et al. 2004) Low High
4
Simulations Mass Space 8 chimp 400 pc @z=6 3x10 6 M Low res, large box High res, small box
5
Numerical Challenges Enough resolution to do reionization right (resolving Lyman-limit systems) Enough volume to model observable (i.e. bright enough) galaxies L ObservationSimulation Limited box sizeLimiting flux Bigger simulationDeeper observation Lyman-Limit systems
6
We Do Not Know Everything M N(<M) Free parameter: Star Formation Efficiency M N(<M) z = 4z = 6 The real test for a simulation is to fit two luminosity functions at two different redshifts simultaneously!
7
Reionization? Low SFR High SFR High res, small box
8
Luminosity Functions z = 4 High SFR Low SFR z = 6
9
Balancing the Books (Bunker et al. 2004) Low High Uncorrected Corrected
10
Conclusions Simulations of reionization are consistent with the “high” value of SFR at z~6 (~0.02 M /Mpc 3 /yr). Simulations are not consistent with the “low” value (~0.005 M /Mpc 3 /yr). Our simulations have barely enough resolution to make this claim. They need to be confirmed by better ones.
11
The End
12
Title
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.