Showing papers by "Dietrich Lemke published in 2010"
Max Planck Society1, Katholieke Universiteit Leuven2, French Alternative Energies and Atomic Energy Commission3, University of Liège4, Spanish National Research Council5, University of Vienna6, European Space Agency7, European Southern Observatory8, Austrian Institute of Technology9, Graz University of Technology10, European Laboratory for Non-Linear Spectroscopy11, Konkoly Thege Miklós Astronomical Institute12
TL;DR: The Photodetector Array Camera and Spectrometer (PACS) as discussed by the authors is one of the three science instruments on ESA's far infrared and sub-mil- limetre observatory.
Abstract: The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments on ESA's far infrared and submil- limetre observatory. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16 × 25 pixels, each, and two filled silicon bolometer arrays with 16 × 32 and 32 × 64 pixels, respectively, to perform integral-field spectroscopy and imaging photom- etry in the 60−210 μm wavelength regime. In photometry mode, it simultaneously images two bands, 60−85 μ mo r 85−125 μ ma nd 125−210 μm, over a field of view of ∼1.75 � × 3.5 � , with close to Nyquist beam sampling in each band. In spectroscopy mode, it images afi eld of 47 �� × 47 �� , resolved into 5 × 5 pixels, with an instantaneous spectral coverage of ∼ 1500 km s −1 and a spectral resolution of ∼175 km s −1 . We summarise the design of the instrument, describe observing modes, calibration, and data analysis methods, and present our current assessment of the in-orbit performance of the instrument based on the performance verification tests. PACS is fully operational, and the achieved performance is close to or better than the pre-launch predictions.
2,645 citations
Max Planck Society1, Katholieke Universiteit Leuven2, French Alternative Energies and Atomic Energy Commission3, University of Liège4, Spanish National Research Council5, University of Vienna6, European Space Agency7, European Southern Observatory8, Austrian Institute of Technology9, Graz University of Technology10, European Laboratory for Non-Linear Spectroscopy11, Konkoly Thege Miklós Astronomical Institute12
TL;DR: The Photodetector Array Camera and Spectrometer (PACS) as discussed by the authors is one of the three science instruments on ESA's far infrared and submillimetre observatory.
Abstract: The Photodetector Array Camera and Spectrometer (PACS) is one of the three science instruments on ESA's far infrared and submillimetre observatory. It employs two Ge:Ga photoconductor arrays (stressed and unstressed) with 16x25 pixels, each, and two filled silicon bolometer arrays with 16x32 and 32x64 pixels, respectively, to perform integral-field spectroscopy and imaging photometry in the 60-210\mu\ m wavelength regime. In photometry mode, it simultaneously images two bands, 60-85\mu\ m or 85-125\mu\m and 125-210\mu\ m, over a field of view of ~1.75'x3.5', with close to Nyquist beam sampling in each band. In spectroscopy mode, it images a field of 47"x47", resolved into 5x5 pixels, with an instantaneous spectral coverage of ~1500km/s and a spectral resolution of ~175km/s. We summarise the design of the instrument, describe observing modes, calibration, and data analysis methods, and present our current assessment of the in-orbit performance of the instrument based on the Performance Verification tests. PACS is fully operational, and the achieved performance is close to or better than the pre-launch predictions.
127 citations
TL;DR: In this article, the authors used PACS photometric bands to detect two sub-mm bright quasars at high redshift: SDSS J1148+5251 (z = 6.42) and BR 1202-0725(z = 4.69) obtained with the PACS instrument.
Abstract: We present Herschel far-infrared (FIR) observations of two sub-mm bright quasars at high redshift: SDSS J1148+5251 (z = 6.42) and BR 1202–0725 (z = 4.69) obtained with the PACS instrument. Both objects are detected in the PACS photometric bands. The Herschel measurements provide additional data points that constrain the FIR spectral energy distributions (SEDs) of both sources, and they emphasise a broad range of dust temperatures in these objects. For λ rest ≲ 20 μ m, the two SEDs are very similar to the average SEDs of quasars at low redshift. In the FIR, however, both quasars show excess emission compared to low-z QSO templates, most likely from cold dust powered by vigorous star formation in the QSO host galaxies. For SDSS J1148+5251 we detect another object at 160 μ m with a distance of ~10´´ from the QSO. Although no physical connection between the quasar and this object can be shown with the available data, it could potentially confuse low-resolution measurements, thus resulting in an overestimate of the FIR luminosity of the z = 6.42 quasar.
38 citations
Book•
30 Sep 2010
26 citations
TL;DR: The final performance and lessons-learnt from the successful acceptance test program of the MIRI wheel mechanism flight models are reported, ready for launch in 2014 by an Ariane 5 rocket.
Abstract: The Mid Infrared Instrument (MIRI) aboard JWST is equipped with one filter wheel and two dichroic-grating wheel
mechanisms to reconfigure the instrument between observing modes such as broad/narrow-band imaging, coronagraphy
and low/medium resolution spectroscopy. Key requirements for the three mechanisms with up to 18 optical elements on
the wheel include: (1) reliable operation at T = 7 K, (2) high positional accuracy of 4 arcsec, (3) low power dissipation,
(4) high vibration capability, (5) functionality at 7 K < T < 300 K and (6) long lifetime (5-10 years). To meet these
requirements a space-proven wheel concept consisting of a central MoS2-lubricated integrated ball bearing, a central
torque motor for actuation, a ratchet system with monolithic CuBe flexural pivots for precise and powerless positioning
and a magnetoresistive position sensor has been implemented. We report here the final performance and lessons-learnt
from the successful acceptance test program of the MIRI wheel mechanism flight models. The mechanisms have been
meanwhile integrated into the flight model of the MIRI instrument, ready for launch in 2014 by an Ariane 5 rocket.
12 citations
01 Jan 2010
TL;DR: Instruments and Methods of Astronomy, Astrophysics, and Cosmology of Landolt-Bornstein - Group VI 'Astronomy and Astrophysysics' as discussed by the authors.
Abstract: This document is part of Subvolume A 'Instruments and Methods' of Volume 4 'Astronomy, Astrophysics, and Cosmology' of Landolt-Bornstein - Group VI 'Astronomy and Astrophysics'.
3 citations