Strong Gravitational Lensing with MeerKAT

Our view of the cosmic evolution of neutral hydrogen and the hydroxyl molecule in galaxies is being transformed through deep surveys with SKA precursors/pathfinders.  Strong gravitational lensing can enable a deeper tier to the ongoing and planned spectral line surveys, without some of the associated calibration risks posed by several thousand-hour integrations; source confusion; image-plane cube combination; and enormous data volumes. In this talk, I will present how relatively modest programmes on MeerKAT targeting known, OIR-identified strong lensing systems are delivering amongst the most distant views of HI and OH emission in galaxies over cosmic time, providing a highly complementary approach to high-redshift spectral-line surveys on MeerKAT, and other facilities. Indeed, strong lensing surveys have leveraged this utility for decades in virtually every part of the electromagnetic spectrum, including almost every major spectral line that traces the interstellar medium in galaxies. MeerKAT’s exquisite sensitivity is demonstrating that we are now able to exploit the power of lensing to explore the high-redshift HI and OH universe.