Cluster magnetic fields from large-scale structure and galaxy cluster shocks
Abstract
The origin of the microgauss magnetic fields in galaxy clusters is one of the outstanding problems of modern cosmology. We have performed three-dimensional particle-in-cell simulations of the nonrelativistic Weibel instability in an electron-proton plasma, in conditions typical of cosmological shocks. These simulations indicate that cluster fields could have been produced by shocks propagating through the intergalactic medium during the formation of large-scale structure or by shocks within the cluster. The strengths of the shock-generated fields range from a few nanogauss in the intercluster medium to a fraction of a microgauss inside galaxy clusters. Further amplification of these fields by sheared turbulent motions and gas accretion in clusters may be expected. Thus, cluster fields may be explained without resorting to the amplification of a primordial field.
Additional Information
© 2006. The American Astronomical Society. Received 2006 February 5; accepted 2006 March 23; published 2006 April 11. L.O.S. acknowledges the help of Michael Marti in performing the simulations and M. Tzonfres, M. Marti, and Professors Ricardo Fonseca and Warren Mori for discussions. M.K. acknowledges useful discussions with X. Chen, E. Nakar, and M. Milosavljevic. The simulations were performed in the eXpp cluster at IST, Lisbon. The work of M.V.M. has been supported by DoE grant DE-FG02-04ER54790, NASA grant NNG-04GM41G, and the GRF fund. The work of L.O.S. was partially supported by the FCT (Portugal) through grants PDCT/FP/FAT/50190/2003 and POCI/FIS/55905/2004. M.K. was supported by DoE grant DE-FG03-92-ER40701 and NASA grant NNG05GF69G.Attached Files
Published - MEDapj06.pdf
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Additional details
- Eprint ID
- 5105
- Resolver ID
- CaltechAUTHORS:MEDapj06
- Department of Energy (DOE)
- DE-FG02-04ER54790
- NASA
- NNG-04GM41G
- GRF fund
- Fundação para a Ciência e a Tecnologia (FCT)
- PDCT/FP/FAT/50190/2003
- Fundação para a Ciência e a Tecnologia (FCT)
- POCI/FIS/55905/2004
- Department of Energy (DOE)
- DE-FG03-92-ER40701
- NASA
- NNG05GF69G
- Created
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2006-10-01Created from EPrint's datestamp field
- Updated
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2019-10-02Created from EPrint's last_modified field