We present an overview of the design and status of the Polarbear -2 and the Simons Array experiments . Polarbear -2 is a Cosmic Microwave Background polarimetry experiment which aims to characterize the arc-minute angular scale B-mode signal from weak gravitational lensing and search for the degree angular scale B-mode signal from inflationary gravitational waves .
The receiver has a 365 mm diameter focal plane cooled to 270 milli-Kelvin .
The focal plane is filled with 7,588 dichroic lenslet-antenna coupled polarization sensitive Transition Edge Sensor ( TES ) bolometric pixels that are sensitive to 95 GHz and 150 GHz bands simultaneously .
The TES bolometers are read-out by SQUIDs with 40 channel frequency domain multiplexing .
Refractive optical elements are made with high purity alumina to achieve high optical throughput .
The receiver is designed to achieve noise equivalent temperature of 5.8 \mu K _ { CMB } \sqrt { s } in each frequency band . Polarbear -2 will deploy in 2016 in the Atacama desert in Chile .
The Simons Array is a project to further increase sensitivity by deploying three Polarbear -2 type receivers .
The Simons Array will cover 95 GHz , 150 GHz and 220 GHz frequency bands for foreground control .
The Simons Array will be able to constrain tensor-to-scalar ratio and sum of neutrino masses to \sigma ( r ) = 6 \times 10 ^ { -3 } at r = 0.1 and \sum m _ { \nu } ( \sigma = 1 ) to 40 meV .