Signatures of Population III supernovae at Cosmic Dawn: the case of
  GN-z11-flash
  We illustrate the observability of the end stages of the earliest (Population
III) stars at high redshifts $z \gtrsim 10$, using the recently observed
transient, GN-z11-flash as an example. We find that the observed spectrum of
this transient is consistent with its originating from a shock-breakout in a
Population III supernova occurring in the GN-z11 galaxy at $z \sim 11$. The
energetics of the explosion indicate a progenitor star of mass $\sim 300
M_{\odot}$ in that galaxy, with of order unity such events expected over an
observing timescale of a few years. We forecast the expected number of such
transients from $z > 10$ galaxies as a function of their host stellar mass and
star formation rate. Our findings are important in the context of future
searches to detect and identify the signatures of galaxies at Cosmic Dawn.
