Pinning down the axion

Physics – Nuclear Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

53

Scientific paper

Davis has argued that, without inflation, the decay of axionic strings is the primary source of axions. This implies a cosmological lower bound on the axion mass of 10-5 to 10-3 eV. In order to obtain a sharper bound it is essential to know the spectrum of emitted axions and the detailed motion of a global string strongly coupled to the axionic field. To this end, we obtain self-consistent, renormalized equations that describe the dynamics of a radiating global string interacting with its surrounding axionic field. We describe the numerical formalism for evolving string trajectories using these equations. From the numerical and analytical evidence we argue that, with appropriate renormalization, the motion of an interacting cosmic string loop can be well approximated by the motion of a free Nambu-Goto string. This implies a lower bound for the axion mass of 10-3 eV. Together with the recent upper bound of 4 × 10-4 eV from the supernova SN1987a, this marginally rules out the invisible axion, or at least pins down the axion mass to a very narrow window around 10-3 eV. This still leaves open the window around 2 eV for hadronic axions, but in that case the axion is no longer a serious dark matter candidate.
Supported in part by NSF Grant PHY 88-05895 and an NSF Graduate Fellowship.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Pinning down the axion does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Pinning down the axion, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pinning down the axion will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1382626

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.