Study and Development of Wide-Band ALMA Receiver Optics Components at NAOJ

At NAOJ, we are studying and developing wide-band receiver optics components to be used in future ALMA wide-band receivers. In particular, we are part of a consortium led by ESO for the development of a wide-band ALMA Band 2 (67-116 GHz) receiver. We have designed and characterized a corrugated horn, OMT and dielectric lens which comply with the stringent ALMA optical requirements over bands 2 and 3. For the study of the lens, we have established a quasi-optical material characterization setup to accurately measure material properties and use those results in lens designs. In addition, we are also collaborating with KASI in the development of a Band7+8 (275-500GHz) receiver. After the successful design and characterization of prototype receiver optics components (corrugated horn and OMT), we are working on the mechanical design of the full optics assembly to minimize loss in the real receiver. We will report the current status and the latest results of this wor k.