Monitoring the stability of thin and medium back-up filters of the Newton-XMM EPIC camera

Abstract

We are conducting a measurement program on back-up filters of the XMM-Newton EPIC camera aimed at monitoring possible aging effects during the mission lifetime. One thin and one medium EPIC back-up filters have been stored since 1997 in an environment similar to that one of the flight filters (dry nitrogen box before launch, high vacuum after launch). The transmission of the two filters has been measured periodically in the 1900-10000 Å wavelength range where effects of aging would be clearly evident. The preliminary results, after 5 years of monitoring, show that a slight aging effect has occurred on both filters which, however, has no significant impact onto the EPIC calibration for the correct analysis of the X-ray astrophysical observations

The Palermo XACT facility: a new 35 m long soft x-ray beam-line for the development and calibration of next-generation x-ray observatories

“…In order to fully exploit the capabilities of high performance X-ray Observatories, filters must be accurately designed, built, and tested. The XACT facility research group is largely involved in the design and calibration of filters for some of the instruments on-board the major X-ray observatories such as the HRC on board Chandra 2,3,4,5,6,7 , the EPIC camera on board Newton XMM 8,9,10 , the X-Ray Telescope on board SOLAR-B 13,14 . Different calibration measurements have been performed including: spatially resolved X-ray transmission measurements, high spectral resolution UV/Visible transmission measurements, spatially resolved UV transmission measurements.…”

“…• Testing and calibration of the filters for the EPIC camera on board XMM-Newton 8,9,10 ; • Testing of filters for the CCD camera of JET-X 11 ;…”

Calibration of the lunar orbital x-ray fluorescence imaging spectrometer (LOXIA) of Chang'E-1 satellite at INAF-OAPA

“…• Testing and calibration of the filters for the EPIC camera on board XMM-Newton [8,9]; • Testing of filters for the CCD camera of JET-X [10];…”

The optical blocking filter for the ATHENA wide field imager: ongoing activities towards the conceptual design

“…The calculations are derived by the use of the matrix formulation of the boundary conditions of the electromagnetic field [16], with the refractive index of aluminum derived from three different sources for the wavelength range 0.01653 ÷ 32 µm [17], 33.333 ÷ 200 µm [18], and 248 ÷1240 µm [19], respectively, and the refractive index of polyimide derived from Cavadi et al 2001 [20]. Upon our experience, based on UV/Vis transmission measurements [21] and X-ray photoelectron spectroscopy measurements [9], we have assumed that an oxide layer of 50 Å builds up on each side of the aluminum coating on polyimide and becomes nearly transparent to UV/Vis radiation. For this reason, only the effective bulk aluminum layer has been conservatively taken into account in the calculation.…”