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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Helical magnetic fields from sphaleron decay and baryogenesis.
Craig J Copi1, Francesc Ferrer, Tanmay Vachaspati
1CERCA, Department of Physics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106-7079, USA.
Physical Review Letters
|November 13, 2008
Summary
Baryogenesis models generate helical cosmic magnetic fields through electroweak dynamics. These fields, though weaker than predicted, offer a new way to study particle physics and CP violation.
Area of Science:
- Cosmology
- Particle Physics
- Astrophysics
Background:
- Baryogenesis models often invoke anomalous particle physics for baryon number violation.
- Understanding the origin of cosmic magnetic fields is a key challenge in astrophysics.
Purpose of the Study:
- To investigate the generation of helical cosmic magnetic fields by baryogenesis.
- To compare numerical results with analytical estimates of magnetic field helicity.
Main Methods:
- Numerical evolution of electroweak equations on a lattice.
- Analysis of Chern-Simons number and electromagnetic helicity conservation.
Main Results:
- Baryogenesis in these models creates helical cosmic magnetic fields.
- The generated helicity is smaller than predicted by earlier analytical estimates.
- Electroweak dynamics conserve Chern-Simons number and total electromagnetic helicity after a transitory period.
Conclusions:
- Baryogenesis can produce astrophysically relevant magnetic fields of nano-Gauss strength.
- Helical magnetic fields serve as an independent probe for baryogenesis and CP violation.
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