The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory

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

Case report: an unexpected link between partial deletion of the SHANK3 gene and Heller’s dementia infantilis, a rare subtype of autism spectrum disorder

International audienceAbstractBackgroundDeletions and mutations involving the SHANK3 gene lead to a nonspecific clinical presentation with moderate to profound intellectual disability, severely delayed or absent speech, and autism spectrum disorders (ASD).Better knowledge of the clinical spectrum of SHANK3 haploinsufficiency is useful to facilitate clinical care monitoring and to guide molecular diagnosis, essential for genetic counselling.Case presentationHere, we report a detailed clinical description of a 10-year-old girl carrying a pathogenic interstitial 22q13.3 deletion encompassing only the first 17 exons of SHANK3.The clinical features displayed by the girl strongly suggested the diagnosis of dementia infantilis, described by Heller in 1908, also known as childhood disintegrative disorder.ConclusionOur present case confirms several observations according to which regression may be part of the clinical phenotype of SHANK3 haploinsufficiency. Therefore, we think it is crucial to look for mutations in the gene SHANK3 in patients diagnosed for childhood disintegrative disorder or any developmental disorder with a regressive pattern involving social and communicative skills as well as cognitive and instinctual functions, with onset around 3 years

A 4.2 K readout channel in a standard 0.7 μ\mum CMOS process for a photoconductor array camera

The cryogenic design of a cold CMOS readout channel to be used in the Photoconductor Array Camera and Spectrometer (PACS) aboard the Herschel Space Observatory (HSO, formerly called FIRST) [1], is presented. Robust architectures and optimized sizing reduce the effect of cryogenic anomalities on the circuit. Simulation results and tests, both at room temperature and 4 K show a non-linearity $<$2%, a hysteresis of <5mV and noise < 100nV/Hz$^{1/2}$ @ 30Hz

Demonstration of an 4.2 K analog switch matrix in a standard 0.7 μ\mu CMOS process

In this extended abstract a $4\times 4$ Field Programmable Analogue Array or switch matrix is presented. Design and preliminary data will be discussed

Locating cavities using ghost scattered waves in a scale-model experiment

The investigation and detection of near-surface structures (cavities, caves, tunnels, mineshafts, buried objects, archeological ruins, water reservoir, etc.) is important to mitigate geo- and environmental hazards. We use a method inspired by seismic interferometry to estimate the location of a cavity in a scaled ultrasonic experiment, representative for geophysical field problems. We use only one source at the surface and retrieve ghost scattered waves by evaluating the correlation of scattered waves at different receiver locations. As an exploitation of the ghost arrival information, the ghost travel times are determined and combined to estimate the location of a cavity with good accuracy.Geoscience & EngineeringCivil Engineering and Geoscience