First demonstration of spectral imaging with QUBIC

Measurements in the lab at APC demonstrate the feasibility of spectral imaging with QUBIC.  We are using the artificial millimetre-wave source to illuminate the QUBIC telescope, and by scanning the instrument in azimuth and elevation we make a map of the source.  Afterwards, using the unique feature of bolometric interferometry which has a sharply frequency dependent beam on the sky, we can do a data analysis which separates the map into different frequency bands (or colours of radio light).    The frequency dependent beam of QUBIC is shown in the upper left of the image below.  The spectral response is shown in the curve on the top right.  The bottom five images are the maps made with QUBIC at each of the frequency bands.  The bright point at the centre is the calibration source.  As expected, the source is visible in the centre band, and faint in the adjacent bands, and invisible in the outside bands.

QUBIC spectral imaging

First empirical demonstration of spectral imaging using bolometric interferometry