Speaker
Description
The CERN Axion Solar Telescope (CAST) was a solar axion helioscope,
which produced the most stringent limits on multiple different
axion like particle candidate couplings by utilizing the inverse Primakoff
effect to convert particles into X-rays in a transverse magnetic field.
A gaseous detector based on 7 GridPixes, a combination of a $256
\times 256$ pixel Timepix ASIC and an integrated MicroMegas stage on
top, together with veto scintillators and an FADC, was installed at
CAST in 2017/18. It recorded a total of about $3500\,h$ of
background and $180\,h$ of solar tracking data.
This talk will present the data analysis and limit calculation method
developed for this detector. The method aims to be model agnostic,
allowing for limit calculations on different coupling constants,
provided the solar flux for the particle can be modeled. The focus
will be on a new, improved limit on the the axion-electron coupling
$g_{ae}$ over the previous 2013 limit.
