Development of receiver optics for ALMA bands 1 and 2, and possible synergies with ngVLA

In recent years, NAOJ has contributed designs and production of waveguide and optics components for ALMA bands 1 (35-50 GHz) and 2 (67-116 GHz) receivers. This includes several novel ideas in the design of corrugated horns and OMTs and the application of 3D printing for the fabrication of key components of radio receivers. These frequency bands coincide approximately with bands 5 and 6 of ngVLA, the most promising project in the 2020s to exploit synergies with ALMA with the goal of increasing the scientific output of both facilities. This paper reports on the recent ALMA development results and discusses their future application to ngVLA.