Planck-HFI optical design and pre-flight performances

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which is mapping the Cosmic Microwave Background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present the optical design of the High Frequency Instrument (HFI) together with the optical performances measured during the ground calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to the telescope, and on their significance for the HFI data analysis procedure

Ultrasound Evaluation of Fluid in Knee Recesses at Varying Degrees of Flexion

Objective. Various methods are utilized in daily practice to obtain optimal information on effusion in the knee. Our aim is to investigate which scanning position provides the best information about synovial fluid in the knee by using ultrasound and to evaluate the magnitude of difference for measuring synovial fluid in 3 major recesses (suprapatellar, medial parapatellar, and lateral parapatellar) of the knee according to various degrees of flexion. Methods. Sonographers in 14 European centers documented bilateral knee joint ultrasound examinations on a total of 148 knee joints. The largest sagittal diameter of fluid was measured in scans corresponding to the 3 major recesses at different (0°, 15°, 30°, 45°, 60°, and 90°) degrees of flexion of the knee. The difference of measurement of effusion according to transducer position, knee position, and the interaction between them was investigated by analysis of variance followed by Tukey’s test. Results. No correlation was noted between patient characteristics and ultrasound detection of effusion. The sagittal diameter of synovial fluid in all 3 recesses was greatest at 30° flexion. Analysis of variance and Tukey’s test revealed that the suprapatellar scan and 30° flexion is the best combination for detecting effusion as confirmed by receiver operator characteristic curve analysis. Conclusion. The suprapatellar scan of the knee in 30° flexion was the most sensitive position to detect fluid in knee joints. Sagittal diameter of fluid in all 3 recesses increased with the knee in the 30° flexed position as compared to the extended position

Planck pre-launch status: HFI beam expectations from the optical optimisation of the focal plane

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which will map the cosmic microwave background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data.We present a detailed description of the optical design of the High Frequency Instrument (HFI) together with some of the optical performances measured during the calibration campaigns.We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to ideal telescope elements, and on their significance for the HFI data analysis procedure

Planck-HFI optical design and pre-flight performances

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which is mapping the Cosmic Microwave Background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present the optical design of the High Frequency Instrument (HFI) together with the optical performances measured during the ground calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to the telescope, and on their significance for the HFI data analysis procedure

Planck-HFI optical design and pre-flight performances

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which is mapping the Cosmic Microwave Background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present the optical design of the High Frequency Instrument (HFI) together with the optical performances measured during the ground calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to the telescope, and on their significance for the HFI data analysis procedure