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Latest News about the RGS. XMM - Newton Users Group 19 May 200 5 Andy Pollock on behalf of the RGS consortium. RGS operational news. instruments are operating routinely well hot pixels and columns stable since cooling
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Latest News about the RGS XMM-NewtonUsers Group 19May 2005 Andy Pollock on behalf of the RGS consortium
RGS operational news • instruments are operating routinely well • hot pixels and columns stable since cooling • RGS2 regular setup ADC current limiter errors imposes some limitations (e.g. single CCDs) flight and flight-spare tests underway
RGS calibration - the story so far • ground calibration accuracy ~15-20% finite source distance lack of narrow emission lines at long wavelengths grating efficiency problems at short wavelengths • in-orbit calibrations cross-dispersion scattering RGS2 CCD2 RGS1 correction 2nd order = 1st order (as planned) instrumental oxygen instrumental fluorine short- correction • SAS background models rgsbkgmodel
RGS : new & TBD • rgscombine in the new SAS for adding RGS spectra • rgsregions in the new SAS (for extended-source work) • stability of the RGS • empirical effective-area corrections • absolute calibration • wavelength scale
rgscombine in the next SAS Capella : combined spectra & response matrices
rgsregions in the next SAS • arbitrary cross-dispersion spectrum selection regions • multiple slit spectra
RGS stability • SNR 1E0102-7219 : dRGS -10% • SNR N132D: dRGS ~ -20±5% @ 33.7Å • INS RXJ1856-3754 stable (dPN: < 1%): dRGS ~ -10% • in-flight calibration sources: degradation rather than variability • O-edge stable in Mkn421 • decrease(?) in effective area inconsistent with likely contaminants • PI redistribution under investigation
RGS effective-area corrections • empirical approach • featureless blazar spectra show the same shape • power-law spectra (no breaks in the RGS range!) • calibrate against the Crab • NH (and absorption chemistry) vital • final testing underway ARF CCF
RGS conclusions and future work • response stable so far within about 10% • global corrections give relative calibration better than 5% • wavelength scale • instrumental Silicon • SAS developments rgssuperrmf weak-source methods optimal extraction The RGS is a beautiful instrument for exciting physics. Why is it not more popular among observers ?