Chameleon-photon mixing in a primordial magnetic field

Journal Article · Sun Aug 15 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.82.044033· OSTI ID:21420969

Schelpe, Camilla A. O. ^[1]

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1. Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Cambridge CB3 0WA (United Kingdom)

The existence of a sizable, O(10{sup -10}-10{sup -9} G), cosmological magnetic field in the early Universe has been postulated as a necessary step in certain formation scenarios for the large-scale O({mu}G) magnetic fields found in galaxies and galaxy clusters. If this field exists then it may induce significant mixing between photons and axion-like particles (ALPs) in the early Universe. The resonant conversion of photons into ALPs in a primordial magnetic field has been studied elsewhere by Mirizzi, Redondo and Sigl (2009). Here we consider the nonresonant mixing between photons and scalar ALPs with masses much less than the plasma frequency along the path, with specific reference to the chameleon scalar field model. The mixing would alter the intensity and polarization state of the cosmic microwave background (CMB) radiation. We find that the average modification to the CMB polarization modes is negligible. However the average modification to the CMB intensity spectrum is more significant and we compare this to high-precision measurements of the CMB monopole made by the far infrared absolute spectrophotometer on board the COBE satellite. The resulting 95% confidence limit on the scalar-photon conversion probability in the primordial field (at 100 GHz) is P{sub {gamma}{r_reversible}{phi}<}2.6x10{sup -2}. This corresponds to a degenerate constraint on the photon-scalar coupling strength, g{sub eff}, and the magnitude of the primordial magnetic field. Taking the upper bound on the strength of the primordial magnetic field derived from the CMB power spectra, B{sub {lambda}{<=}5}.0x10{sup -9} G, this would imply an upper bound on the photon-scalar coupling strength in the range g{sub eff} < or approx. 7.14x10{sup -13} GeV{sup -1} to g{sub eff} < or approx. 9.20x10{sup -14} GeV{sup -1}, depending on the power spectrum of the primordial magnetic field.

• OSTI ID: 21420969
• Journal Information: Physical Review. D, Particles Fields, Vol. 82, Issue 4; Other Information: DOI: 10.1103/PhysRevD.82.044033; (c) 2010 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AXIONS
COMPARATIVE EVALUATIONS
COSMOLOGICAL MODELS
COUPLING
GALAXIES
GALAXY CLUSTERS
GHZ RANGE
LANGMUIR FREQUENCY
MAGNETIC FIELDS
MASS
MIXING
MODIFICATIONS
MONOPOLES
PHOTONS
POLARIZATION
RELICT RADIATION
SCALAR FIELDS
SPECTRA
SPECTROPHOTOMETERS
UNIVERSE
BOSONS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
EVALUATION
FREQUENCY RANGE
GOLDSTONE BOSONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
MICROWAVE RADIATION
POSTULATED PARTICLES
RADIATIONS