AdvancedIOAA 2011 | Katowice, Poland | TH S11 | 10 pt

13.6 | When did a distant galaxy form its stars?

A galaxy at redshift $z=6.03$ contains stars whose ages are from 560 to 600 million years. At what redshift did star formation occur in this galaxy?

Assume the present age of the Universe is $t_0=13.7\times10^9$ years and a flat cosmological model with $\Lambda=0$ , in which the scale factor obeys $R\propto t^{2/3}$ .

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Reading resources

Material that covers the physics behind this problem.

An Introduction to Modern AstrophysicsCarroll & Ostlie
The standard reference for olympiad-level astrophysics. Chapters 1-3 cover the celestial sphere, orbits and the magnitude system.
Textbook
Ohio State Astronomy Lecture NotesOhio State University
Clear university-level notes on stars, galaxies and cosmology with derivations you can follow line by line.
Lecture notes
Cosmology CalculatorEdward L. Wright (UCLA)
Converts redshift into distances, lookback time and scale factors. Use it to sanity-check cosmology answers.
Website