Design and Development of a Wide-Field Fully Cryogenic Phased Array Feed for Arecibo

Brigham Young University (BYU), in collaboration with Cornell University, is developing the Advanced Cryogenic L-band Phased Array Camera for Arecibo (ALPACA) as a user provided facility instrument on the Arecibo 305 m radio telescope. This instrument will consist of a fully cryogenic 69-element phased array feed (PAF) and real-time digital beamformer back end capable of producing 40 simultaneous dual polarized beams with approximately 305 MHz of instantaneous bandwidth at 1.4 GHz. The target design goal is to operate with a system noise temperature of 25 K. We report on simulation results and a preliminary overview of the design and progress of the instrument's development.