Instrumental systematics biases in CMB lensing reconstruction: a
  simulation-based assessment
  Weak gravitational lensing of the cosmic microwave background (CMB) is an
important cosmological tool that allows us to learn about the structure,
composition and evolution of the Universe. Upcoming CMB experiments, such as
the Simons Observatory (SO), will provide high-resolution and low-noise CMB
measurements. We consider the impact of instrumental systematics on the
corresponding high-precision lensing reconstruction power spectrum
measurements. We simulate CMB temperature and polarization maps for an SO-like
instrument and potential scanning strategy, and explore systematics relating to
beam asymmetries and offsets, boresight pointing, polarization angle, gain
drifts, gain calibration and electric crosstalk. Our analysis shows that the
majority of the biases induced by the systematics we modeled are below a
detection level of $\sim 0.6\sigma$. We discuss potential mitigation techniques
to further reduce the impact of the more significant systematics, and pave the
way for future lensing-related systematics analyses.
