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SUMMARY:Dark matter revealed by the first stars? - Rennan Barkana
DTSTART:20181029T130000Z
DTEND:20181029T140000Z
UID:TALK111949@talks.cam.ac.uk
CONTACT:Tobias Baldauf
DESCRIPTION:The cosmic radio spectrum is expected to show a strong absorpt
 ion signal around redshift 20 that corresponds to the rise of the first st
 ars\; specifically\, the stellar radiation turns on 21-cm absorption by at
 omic hydrogen. The EDGES global 21-cm experiment has detected the first su
 ch signal\, finding a stronger absorption than the maximum expected. This 
 absorption can be explained by invoking excess cooling of the cosmic gas i
 nduced by an interaction with dark matter. This would have far reaching co
 nsequences\, including an upper limit on the mass of dark matter particles
  that conflicts with the expectations for WIMPs. Specific particle physics
  models are highly constrained\, but observations will decide. We will dis
 cuss possible tests and alternative explanations.\n
LOCATION:CMS\, Pav. B\, CTC Common Room (B1.19) [Potter Room]
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