20 research outputs found
FALCO simulations of high-contrast polarimetry with the Nancy Grace Roman Space Telescope Coronagraph Instrument
The Coronagraph Instrument of the Nancy Grace Roman Space Telescope (Roman
Coronagraph) will be capable of both total intensity and polarization
measurements of circumstellar disks. The polarimetric performance is impacted
by polarization effects introduced by all mirrors before the Wollaston prisms.
In this paper, we aim to characterize these effects for the Roman Coronagraph
in bands 1 and 4 using the FALCO and PROPER packages. We simulate the effect of
polarization aberrations that impact the polarimetric contrast and the
instrumental polarization effects to study the polarimetric accuracy. We
include spacecraft rolls, but leave out systematic camera noise. We find that
polarimetric differential imaging (PDI) improves the contrast by a factor of
six. The PDI contrast of is limited by polarized
speckles from instrumental polarization effects and polarization aberrations.
By injecting polarized companions with at various contrast levels and
demodulating their polarimetric signal, we recover their source Stokes vector
within 2%.Comment: 16 pages, 16 figures, SPIE Optics + Photonics - Techniques and
Instrumentation for Detection of Exoplanets X
EURECA: European-Japanese microcalorimeter array
The EURECA project aims to demonstrate technological readiness of a micro-calorimeter array for application in future X-ray astronomy missions, like Constellation-X, EDGE, and XEUS. The prototype instrument consists of a 5 × 5 pixel array of TES-based micro-calorimeters read out by two SQUID-amplifier channels using frequency-domain-multiplexing (FDM) with digital base-band feedback. The detector array is cooled by a cryogen-free cryostat consisting of a pulse tube cooler and a two stage ADR. Initial tests of the system at the PTB beam line of the BESSY synchrotron showed stable performance and an X-ray energy resolution of 1.5 eV at 250 eV for read-out of one TES-pixel only. Next step is deployment of FDM to read-out the full array. Full performance demonstration is expected end 2008.This work was financially supported by the Dutch Organization for Scientific Research
(NWO).Peer Reviewe
[email protected]; phone +31 30 2535710; fax +31 30 2540860, www.sron.nl Space Telescopes and Instrumentation
ABSTRACT The EURECA (EURopean-JapanEse Calorimeter Array) project aims to demonstrate the science performance and technological readiness of an imaging X-ray spectrometer based on a micro-calorimeter array for application in future X-ray astronomy missions, like Constellation-X and XEUS. The prototype instrument consists of a 5 x 5 pixel array of TES-based micro-calorimeters read out by by two SQUID-amplifier channels using frequency-domain-multiplexing (FDM). The SQUID-amplifiers are linearized by digital base-band feedback. The detector array is cooled in a cryogenfree cryostat consisting of a pulse tube cooler and a two stage ADR. A European-Japanese consortium designs, fabricates, and tests this prototype instrument. This paper describes the instrument concept, and shows the design and status of the various sub-units, like the TES detector array, LC-filters, SQUID-amplifiers, AC-bias sources, digital electronics, etc. Initial tests of the system at the PTB beam line of the BESSY synchrotron showed stable performance and an X-ray energy resolution of 1.58 eV at 250 eV and 2.5 eV @ 5.9 keV for the read-out of one TES-pixel only. Next step is deployment of FDM to read-out the full array. Full performance demonstration is expected mid 2009
Progress in Antenna Coupled Kinetic Inductance Detectors
This paper describes the combined Dutch efforts toward the development of large wideband focal plane array receivers based on kinetic inductance detectors (KIDs). Taking into account strict electromagnetic and detector sensitivity requirements for future ground and space based observatories, this work has led to the identification of well-suited coupling strategies based on the use of lens antenna and the demonstration of their feasibility. Moreover, some specific antenna design difficulties that characterize KIDs-based designs have been investigated, and innovative feeds for the focal plane array which could allow the receivers to be sensitive over a decade of Bandwidth have been proposed. © 2011 IEEE