UV Spectral Slopes at z = 6−9 in the Hubble Frontier Fields: Lack of Evidence for Unusual or Population III Stellar Populations

  title={UV Spectral Slopes at z = 6−9 in the Hubble Frontier Fields: Lack of Evidence for Unusual or Population III Stellar Populations},
  author={Rachana Bhatawdekar and Christopher J. Conselice},
  journal={The Astrophysical Journal},
We present new measurements of the UV spectral slope β for galaxies at z = 6−9 in the Frontier Field cluster MACS J0416.1–2403 and its parallel field to an unprecedented level of low stellar mass. We fit synthetic stellar population models to the observed spectral energy distribution and calculate β by fitting a power law to the best-fit spectrum. With this method, we report the derivation of rest-frame UV colors of galaxies for the Frontier Fields program extending out to z = 9, probing… Expand
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