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LEMUR is a VUV imaging spectrograph with 0.28" resolution. Incident solar radiation is imaged onto the spectrograph slit by a single mirror telescope consisting of a 30-cm steerable f/12 off-axis paraboloid mirror. The spectrograph slit is imaged and dispersed by a highly corrected grating that focuses the solar spectrum over the detectors. The mirror is coated with a suitable multilayer with B4C top-coating providing a reflectance peak around 18.5 nm besides the usual B4C range above 500A. The grating is formed by two halves, one optimized for performances around 185A and the other above 500A. Three intensified CCD cameras will record spectra above 50 nm while a large format CCD array with an aluminum filter will be used around 185A.

We report on a new instrument that brings high efficiency to x-ray polarimetry, which is the last unexplored field of x-ray astronomy. It derives the polarization information from the tracks of the photoelectrons imaged by a finely subdivided gas pixel detector. The device can also do simultaneously good imaging, moderate spectroscopy and fast, high rate timing down to 150 eV. Moreover, being truly 2D, it is non dispersive and does not require rotation. The great immprovement of sensitivity will allow direct exploration of the most dramatic objects of the x-ray sky; with integrations of the order of one day we could perform polarimetry of Active Galactic Nuclei at the percent level, a breakthrough in this fascinating window of high energy astrophysics.

We report on the development of a new higly efficient polarimeter, based on the photoelectric effect in gas, for the 2-10 keV energy range, a particularly interesting band for x-ray astronomy. We derive the polarization information by reconstructing the direction of photoelectron emission with a pixel gas detector. Attention is focused on the algorithms used in data analysis in order to maximize the sensitivity of the instrument. Monte Carlo simulation is also discussed in details.

BaR-SPOrt (Balloon-borne Radiometers for Sky Polarisation Observations) is an experiment to measure the linearly polarized emission of sky patches at 32 and 90 GHz with sub-degree angular resolution. It is equipped with high sensitivity correlation polarimeters for simultaneous detection of both the U and Q stokes parameters of the incident radiation. On-axis telescope is used to observe angular scales where the expected polarization of the Cosmic Microwave Background (CMBP) peaks. This project shares most of the know-how and sophisticated technology developed for the SPOrt experiment onboard the International Space Station. The payload is designed to flight onboard long duration stratospheric balloons both in the Northern and Southern hemispheres where low foreground emission sky patches are accessible. Due to the weakness of the expected CMBP signal (in the range of microK), much care has been spent to optimize the instrument design with respect to the systematics generation, observing time efficiency and long term stability. In this contribution we present the instrument design, and first tests on some components of the 32 GHz radiometer., Comment: 12 pages, 10 figures, Astronomical Telescopes and Instrumentation (Polaimetry in Astronomy) Hawaii August 2002 SPIE Meeting