In-Flight Calibration of the ROSAT HRI UV Sensitivity
نویسندگان
چکیده
Comparing measured and estimated count rates of a few selected sample stars, we connrm the validity and provide the in-ight calibration of the ROSAT HRI UV/Visible eeective area model in Zombeck et al. 1997, ApJ, 487, L69. The count rate estimates for Betelgeuse derived with this model are in agreement with the measured HRI upper limit. This result is also connrmed in an erratum by Berghh ofer et al. (2000, A&A, 357, 387) aimed at revising their previous calculation (Berghh ofer et al. 1999, A&A, 342, L17) which was overestimated by more than two orders of magnitude. Adopting this ROSAT HRI UV/Visible eeective area model and measured UV/Visible spectra of a set of sample stars covering the range of T ef f 3000-40000 K, we have built the calibration curves to estimate UV/Visible contamination count rates for any star of known T ef f , m v , and N H .
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