Developments and enhancements to the HELIOS pump probe system

•A HHG gas cell is redesigned to have different interaction lengths based on phase matching calculations from the literature.•It was found that the maximum photon flux (up to 1010 photons/s at 42eV) is very dependent on the size of the gas cell.•Optimizing the gas cell dimensions allowed for the generation of He HHG up to 72 eV, previously unachievable by the system.•The paper reports on the conversion efficiency and temporal pulse width of a newly installed frequency trippler system. In this progress report we describe several design improvements that have been implemented at the HELIOS laboratory, as well as presenting the output characteristics that have been measured as a result. The main focus will be on the redesign of the gas cell, which has enhanced the photon flux of the XUV probe beam. Also, a frequency trippler utilizing sum frequency generation has been installed at the end of the pump line, which increases the photon flux available for both 3.1eV (400nm) and 4.66eV (266nm) applications without significant increment in the pulse width of the pump.