C II* Absorption in Damped Lyα Systems. I. Star Formation Rates in a Two-Phase Medium

  title={C II* Absorption in Damped Ly$\alpha$ Systems. I. Star Formation Rates in a Two-Phase Medium},
  author={Arthur M. Wolfe and Jason Xavier Prochaska and Eric Gawiser},
  journal={The Astrophysical Journal},
We describe a technique that for the first time measures star formation rates (SFRs) in damped Lyα systems (DLAs) directly. We assume that massive stars form in DLAs and that the far-ultraviolet (FUV) radiation they emit heats the gas by the grain photoelectric mechanism. We infer the heating rate by equating it to the cooling rate measured by the strength of C II* λ1335.7 absorption. Since the heating rate is proportional to the product of the dust-to-gas ratio, the grain photoelectric heating… 

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