Commissioning the Yuan-Tseh Lee Array for Epoch of Reionization Observations with Intensity Mapping

The Yuan-Tseh Lee Array (YTLA) is a coplanar 13 element interferometer, which is located on Mauna Loa, Hawaii at an altitude of 3400 m on a 6 meter hexapod platform. The YTLA (formerly the Array for Microwave Background Anisotropy AMiBA) was commissioned in 2006 to study the Cosmic Microwave Background (CMB) using the thermal Sunyaev-Zeldovich (SZ) effect. The frequency of operation is in W-band (86 GHz - 102 GHz). The receiver system consists of cryogenically cooled (15 K) Low Noise Amplifiers (LNA) with a sub-harmonic mixer for the Radio Frequency (RF) to Intermediate Frequency (IF) downconversion stage. In addition, each receiver is equipped with an Ortho-Mode Transducer (OMT) to separate the two polarizations. A fixed primary Local Oscillator (LO) at 84 GHz is used to generate an IF from 2 - 18 GHz. Lag correlators using analog multipliers which provide large bandwidth and moderate frequency resolution were employed for the SZ observations. The experiment was concluded in 2014, and subsequently, plans were initiated to repurpose the telescope to study the Epoch of Reionization (EoR) using Carbon Monoxide (CO) at high redshifts (z~6) with Intensity Mapping (IM) techniques. Using IM, one can study aggregate emission from several galaxies (~100 - 1000) spread over large angular scales on the sky.