Receiver optics for ALMA band 11 (1.25–1.57 THz)

The current ALMA telescope covers all atmospheric windows from 35 to 950 GHz. However, atmospheric conditions in the ALMA site could potentially allow astronomical observations in the 1.25-1.57 THz band. Recently, we demonstrated the possibility to manufacture high-quality corrugated horns for this band. In this paper, we describe the design of ALMA compliant receiver optics using the fabricated corrugated horns. The optics is based on the ALMA band 10 optics design and consists of two ellipsoidal mirrors. Simulations show excellent performance. Beam measurements will be done in the coming months and presented at the conference.