Strong magnetic fields in normal galaxies at high redshifts
arXiv:0807.3347 · doi:10.1038/nature07105
Abstract
The origin and growth of magnetic fields in galaxies is still something of an enigma. It is generally assumed that seed fields are amplified over time through the dynamo effect, but there are few constraints on the timescale. It has recently been demonstrated that field strengths as traced by rotation measures of distant quasars are comparable to those seen today, but it was unclear whether the high fields were in the exotic environments of the quasars themselves or distributed along the line of sight. Here we demonstrate that the quasars with strong MgII absorption lines are unambiguously associated with larger rotation measures. Since MgII absorption occurs in the haloes of normal galaxies along the sightline to the quasars, this association requires that organized fields of surprisingly high strength are associated with normal galaxies when the Universe was only about one-third of its present age.
11 pages, 2 figures, Letter to Nature, accepted. Final version available at http://www.nature.com/nature/journal/v454/n7202/abs/nature07105.html
References in corpus (4)
Cited by in corpus (10)
- Magnetic fields from inflation?
- Evolution of magnetic fields in galaxies and future observational tests with the Square Kilometre Array
- Gamma-ray induced cascades and magnetic fields in intergalactic medium
- Reionization - A probe for the stellar population and the physics of the early universe
- The influence of magnetic fields on the thermodynamics of primordial star formation
- An 84 microGauss Magnetic Field in a Galaxy at Redshift z=0.692
- Can the observed large scale magnetic fields be seeded by helical primordial fields?
- Measuring interstellar magnetic fields by radio synchrotron emission
- Cosmic Magnetism with the Square Kilometre Array and its Pathfinders
- Testing the cosmological evolution of magnetic fields in galaxies with the SKA