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Silicon pore optics is a technology developed to enable future large area X-ray telescopes, such as the International Xray Observatory (IXO), a candidate mission in the ESA Space Science Programme 'Cosmic Visions 2015-2025'. IXO uses nested mirrors in Wolter-I configuration to focus grazing incidence X-ray photons on a detector plane. The IXO mirrors will have to meet stringent performance requirements including an effective area of ~3 m² at 1.25 keV and ~1 m² at 6 keV and angular resolution better than 5 arc seconds. To achieve the collecting area requires a total polished mirror surface area of ~1300 m² with a surface roughness better than 0.5 nm rms. By using commercial high-quality 12" silicon wafers which are diced, structured, wedged, coated, bent and stacked the stringent performance requirements of IXO can be attained without any costly polishing steps. Two of these stacks are then assembled into a co-aligned mirror module, which is a complete X-ray imaging system. Included in the mirror module are the isostatic mounting points, providing a reliable interface to the telescope. Hundreds of such mirror modules are finally integrated into petals, and mounted onto the spacecraft to form an X-ray optic of four meters in diameter. In this paper we will present the silicon pore optics assembly process and latest X-ray results. The required metrology is described in detail and experimental methods are shown, which allow to assess the quality of the HPOs during production and to predict the performance when measured in synchrotron radiation facilities.

This paper was presented at the SPIE conference on Astronomical Instrumentation 2010 conference.

The Mid Infrared Instrument (MIRI), one of the four instruments on the Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST), supports all of the science objectives of the observatory. MIRI optical alignment is an important step in the verification process, directly affecting mission success. The MIRI optical alignment is verified on the ground at the integrated ISIM level using an element in the MIRI Filter Wheel, the pupil alignment reference (PAR), developed by NASA GSFC and provided to MIRI. It is a ~2.3g aluminum piece that has a flat, specularly reflective, 3mm diameter surface in its center, with laser-etched fiducials within its aperture. The PAR is illuminated via an optical stimulus (ground support equipment) and imaged using a pupil imaging camera, during the ISIM test program in order to determine absolute and relative changes in the alignment that impact pupil shear and roll. Here we describe the MIRI PAR; its physical properties and challenges during its design, manufacturing, and testing.

The James Webb Space Telescope, an infrared-optimized space telescope being developed by NASA for launch in 2014, will utilize cutting-edge detector technology in its investigation of fundamental questions in astrophysics. JWST's near infrared spectrograph, NIRSpec utilizes two 2048 × 2048 HdCdTe arrays with Sidecar ASIC readout electronics developed by Teledyne to provide spectral coverage from 0.6 microns to 5 microns. We present recent test and calibration results for the "pathfinder NIRSpec detector subsystem" as well as data processing routines for noise reduction and cosmic ray rejection.

The Mid-Infrared Instrument (MIRI) is one of four scientific instruments on the James Webb Space Telescope (JWST) observatory, scheduled for launch in 2014. It will provide unique capabilities to probe the deeply dust-enshrouded regions of the Universe, investigating the history of star formation both near and far. The MIRI is the coldest instrument on the observatory. Its thermal design is driven by requirements to cool an Optics Module (OM) to below 15.5 K and detectors within this to below 6.7 K with a stability of \ml10 mK over 1000 seconds. The OM is accommodated within the JWST Integrated Science Instrument Module (ISIM) which is cooled passively to between 32 and 40 K. The instrument temperatures are achieved by a combination of thermal isolation of the OM and the ISIM supplemented with active cooling of the OM by a dedicated cryo-cooler. A flight representative "verification model" underwent two cryogenic thermal test campaigns at the UK's STFC Rutherford Appleton Laboratory between December 2007 and September 2008. This paper begins by summarizing the thermal design of the MIRI OM and describing the design of the cryogenic test facility. It goes on to describe the two test campaigns and the correlation of the MIRI OM thermal model to the thermal balance test measurements, concluding with the predicted in-flight thermal performance of the instrument based on this testing.

In the frame of ESA Cosmic Vision assessment study, Thales propose a 3.5m diameter Ritchey-Chretien telescope in HB-Cesic ceramics. The evaluation of its performances demonstrate that the proposed design perfectly fulfils the mission requirements. The objective of this paper is to provide to the reader an overview of the telescope design and performances of the HB-Cesic SPICA Telescope. The development plan is also addressed. It has been established to minimize risks and schedule. The last point is a sensitivity analysis to pupil diameter reduction: an interesting way to further reduce development schedule.

Aims. We study the massive stars in OB associations and their surrounding interstellar medium environment, using a population synthesis code.

Methods. We developed a new population synthesis code for groups of massive stars, where we model the emission of different forms of energy and matter from the stars of the association. In particular, the ejection of the two radioactive isotopes ²⁶Al and ⁶⁰Fe is followed, as well as the emission of hydrogen ionizing photons, and the kinetic energy of the stellar winds and supernova explosions. We investigate various alternative astrophysical inputs and the resulting output sensitivities, especially effects due to the inclusion of rotation in stellar models. As the aim of the code is the application to relatively small populations of massive stars, special care is taken to address their statistical properties. Our code incorporates both analytical statistical methods applicable to small populations, as well as extensive Monte Carlo simulations.

MIRI is the mid-IR instrument for the James Webb Space Telescope and provides imaging, coronography and integral field spectroscopy over the 5-28 micron wavelength range. MIRI is the only instrument which is cooled to 7K by a dedicated cooler, much lower than the passively cooled 40K of the rest of JWST, which introduces unique challenges. The paper will describe the key features of the overall instrument design. The flight model design of the MIRI Optical System is completed, with hardware now in manufacture across Europe and the USA, while the MIRI Cooler System is at PDR level development. A brief description of how the different development stages of the optical and cooling systems are accommodated is provided, but the paper largely describes progress with the MIRI Optical System. We report the current status of the development and provide an overview of the results from the qualification and test programme.