Bibcode
Hoyland, R. J.; Aguiar-González, M.; Aja, B.; Ariño, J.; Artal, E.; Barreiro, R. B.; Blackhurst, E. J.; Cagigas, J.; Cano de Diego, J. L.; Casas, F. J.; Davis, R. J.; Dickinson, C.; Arriaga, B. E.; Fernandez-Cobos, R.; de la Fuente, L.; Génova-Santos, R.; Gómez, A.; Gomez, C.; Gómez-Reñasco, F.; Grainge, K.; Harper, S.; Herran, D.; Herreros, J. M.; Herrera, G. A.; Hobson, M. P.; Lasenby, A. N.; Lopez-Caniego, M.; López-Caraballo, C.; Maffei, B.; Martinez-Gonzalez, E.; McCulloch, M.; Melhuish, S.; Mediavilla, A.; Murga, G.; Ortiz, D.; Piccirillo, L.; Pisano, G.; Rebolo, R.; Rubiño-Martin, J. A.; Ruiz, J. Luis; Sanchez de la Rosa, V.; Sanquirce, R.; Vega-Moreno, A.; Vielva, P.; Viera-Curbelo, T.; Villa, E.; Vizcargüenaga, A.; Watson, R. A.
Bibliographical reference
Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VI. Proceedings of the SPIE, Volume 8452, id. 845233-845233-15 (2012).
Advertised on:
9
2012
Citations
15
Refereed citations
15
Description
The QUIJOTE-CMB project has been described in previous publications.
Here we present the current status of the QUIJOTE multi-frequency
instrument (MFI) with five separate polarimeters (providing 5
independent sky pixels): two which operate at 10-14 GHz, two which
operate at 16-20 GHz, and a central polarimeter at 30 GHz. The optical
arrangement includes 5 conical corrugated feedhorns staring into a dual
reflector crossed-draconian system, which provides optimal
cross-polarization properties (designed to be < -35 dB) and symmetric
beams. Each horn feeds a novel cryogenic on-axis rotating polar
modulator which can rotate at a speed of up to 1 Hz. The science driver
for this first instrument is the characterization of the galactic
emission. The polarimeters use the polar modulator to derive linear
polar parameters Q, U and I and switch out various systematics. The
detection system provides optimum sensitivity through 2 correlated and 2
total power channels. The system is calibrated using bright polarized
celestial sources and through a secondary calibration source and
antenna. The acquisition system, telescope control and housekeeping are
all linked through a real-time gigabit Ethernet network. All
communication, power and helium gas are passed through a central rotary
joint. The time stamp is synchronized to a GPS time signal. The
acquisition software is based on PLCs written in Beckhoffs TwinCat and
ethercat. The user interface is written in LABVIEW. The status of the
QUIJOTE MFI will be presented including pre-commissioning results and
laboratory testing.