2 research outputs found
First polarised light with the NIKA camera
NIKA is a dual-band camera operating with 315 frequency multiplexed LEKIDs
cooled at 100 mK. NIKA is designed to observe the sky in intensity and
polarisation at 150 and 260 GHz from the IRAM 30-m telescope. It is a
test-bench for the final NIKA2 camera. The incoming linear polarisation is
modulated at four times the mechanical rotation frequency by a warm rotating
multi-layer Half Wave Plate. Then, the signal is analysed by a wire grid and
finally absorbed by the LEKIDs. The small time constant (< 1ms ) of the LEKID
detectors combined with the modulation of the HWP enables the
quasi-simultaneous measurement of the three Stokes parameters I, Q, U,
representing linear polarisation. In this paper we present results of recent
observational campaigns demonstrating the good performance of NIKA in detecting
polarisation at mm wavelength.Comment: 7 pages, Proceeding for Journal of Low Temperature Physic