2 research outputs found
Axion Searches with Helioscopes and astrophysical signatures for axion(-like) particles
The first part reviews the working mechanisms, capabilities and performance
of axion helioscopes, including the achieved results so far. The 2nd part is
observationally driven. New simulation results obtained with the Geant4 code
reconstruct spectral shape of solar X-ray spectra, and their isotropic emission
and lateral size. The derived rst mass of the axion(-like) particles is ~10meV.
The axion interaction with magnetic field gradient is a generic theoretical
suggestion that could reconcile present limits with relevant solar X-ray
activity. A short outlook of the experimentally expanding solar axion field is
given.Comment: 31 pages, 18 figures. Aded 1 author, updated references. Accepted for
the special issue of NJP on dark matter (July 2009
Production and Detection of Axion-Like Particles at the VUV-FEL: Letter of Intent.
Recently, the PVLAS collaboration has reported evidence for an anomalously
large rotation of the polarization of light generated in vacuum in the presence
of a transverse magnetic field. This may be explained through the production of
a new light spin-zero particle coupled to two photons. In this Letter of
Intent, we propose to test this hypothesis by setting up a photon regeneration
experiment which exploits the photon beam of the Vacuum-UltraViolet
Free-Electron Laser VUV-FEL, sent along the transverse magnetic field of a
linear arrangement of dipole magnets of size B L ~ 30 Tm. The high photon
energies available at the VUV-FEL increase substantially the expected photon
regeneration rate in the mass range implied by the PVLAS anomaly, in comparison
to the rate expected at visible lasers of similar power. We find that the
particle interpretation of the PVLAS result can be tested within a short
running period. The pseudoscalar vs. scalar nature can be determined by varying
the direction of the magnetic field with respect to the laser polarization. The
mass of the particle can be measured by running at different photon energies.
The proposed experiment offers a window of opportunity for a firm establishment
or exclusion of the particle interpretation of the PVLAS anomaly before other
experiments can compete.Comment: 5 pages, 4 figures, submitted to HASYLAB and DESY Physics Research
Committee on March 31, 200