On 3/4/16 1:34 AM, Robert L. Oldershaw wrote:
Also intriguing is the report in yesterday's Nature that some FRB
sources appear to repeat, which apparently means they are single
ultracompact objects rather than mergers.


In your referenced paper:
E. F. Keane, et al.,
The host galaxy of a fast radio burst
Nature doi:10.1038/nature17140
and a quote therein:

"The dispersion measure and redshift, in combination,
provide a direct measurement of the
cosmic density of ionized baryons
in the intergalactic medium of
Omega_IGM = 4.9 +/- 1.3 percent"

It is important to note 4.9 percent refers to ionized baryons
and is not an indicator of non ionized baryons,
if they exist,
outside present Big Bang nucleosynthetic formulations.

RDS

[Mod. note: non-ASCII characters removed. PLEASE DO NOT CUT AND PASTE
FORMULAE FROM PAPERS -- mjh]