M. Karuza

New PVLAS results and limits on magnetically induced optical rotation and ellipticity in vacuum

In 2006 the PVLAS collaboration reported the observation of an optical rotation generated in vacuum by a magnetic field. To further check against possible instrumental artifacts, several upgrades to the PVLAS apparatus have been made during the past year. Two data taking runs, at the wavelength of 1064 nm, have been performed in the new configuration with magnetic field strengths of 2.3 and 5 T. The 2.3 T field value was chosen in order to avoid stray fields. The new observations do not show the presence of a rotation signal down to the levels of

Search for Sub-eV Mass Solar Axions by the CERN Axion Solar Telescope with 3He Buffer Gas

1.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}\text{ }\text{ }\mathrm{rad}

Conceptual design of the International Axion Observatory (IAXO)

at 5 T and

New CAST limit on the axion–photon interaction

1.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}\text{ }\text{ }\mathrm{rad}

Search for solar axions by the CERN axion solar telescope with 3He buffer gas: closing the hot dark matter gap.

at 2.3 T (at 95% C.L.) with 45 000 passes in the magnetic field zone. In the same conditions no ellipticity signal was detected down to

Optomechanically induced transparency in a membrane-in-the-middle setup at room temperature

1.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}8}

Limits on low energy photon-photon scattering from an experiment on magnetic vacuum birefringence

at 2.3 T (at 95% C.L.), whereas at 5 T a signal is still present. The physical nature of this ellipticity as due to an effect depending on

Optomechanical sideband cooling of a thin membrane within a cavity

{B}^{2}

Quantum dynamics of an optical cavity coupled to a thin semitransparent membrane: Effect of membrane absorption

can be excluded by the measurement at 2.3 T. These new results completely exclude the previously published magnetically induced vacuum dichroism results, indicating that they were instrumental artifacts. These new results therefore also exclude the particle interpretation of the previous PVLAS results as due to a spin-zero boson. The background ellipticity at 2.3 T can be used to determine a new limit on the total photon-photon scattering cross section of

New solar axion search using the CERN Axion Solar Telescope with He 4 filling

{\ensuremath{\sigma}}_{\ensuremath{\gamma}\ensuremath{\gamma}}l4.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}34}\text{ }\text{ }\mathrm{barn}