All Figures

Figure 1: The ToO ( left) and the archival ( right) RGS-1 spectra of Mkn 421 in the [22.5-24] Å  band, together with the best-fit power-law models ( upper panels). In the right panel, the solid and the dotted lines refer to the first and the second exposures of November 4, 2002, respectively, the short-dashed one represents the December 1, 2002 data while the long-dashed data are those taken in June 2003. In the middle panel we report the residuals left by the best-fit models and in the bottom panel the RGS-1 effective areas.

Open with DEXTER


In the text

Figure 2: The RGS-1 (dark gray data) and the RGS-2 [18-20.3] Å  spectra (light gray data) of Mkn 421 during the ToO observation of November 2003. We also show the respective best-fit power-law models (dashed lines). In the mid panel we report the residuals left by the best-fit models and in the bottom panel the effective areas. The RGS-2 effective area decays above  Å  because of the CCD-4 failure.

Open with DEXTER


In the text

Figure 3: The RGS-1 [18-20.3] Å  ( left) and the RGS-2 [18-20] Å  ( right) archival spectra of Mkn 421, together with the best-fit power-law models ( upper panels). The solid and dotted data refer to the first and the second exposures of November 4, 2002, respectively, the short-dashed ones represent the December 1, 2002 data while the long-dashed ones the June 2003 data. In the mid panel we report the residuals left by the best-fit models and in the bottom panel the effective areas. We limit the RGS-2 plot to the [18-20] Å  range because of the CCD-4 failure.

Open with DEXTER


In the text

	Figure 4: Residuals left by the best-fit power-law model to the [18-20] Å  RGS-1 spectrum of the Crab ( upper panel). In the lower panel we show the relative RGS-1 effective area.
Open with DEXTER


In the text

Figure 5: The RGS-1 spectra of Mkn 421 in the [21-22] Å  range. In the left panel we show the November 2003 ToO spectrum and in the right panel the archival data ( upper panels), together with the best-fit models. On the right, we show with a solid and a dotted line the two exposures of November 4, 2002, with a short-dashed line the December 1, 2002 data and with a long-dashed line the June 2003 data. In the middle panels we display the residuals left by the best-fit models and in the lower panels the RGS-1 effective areas of the RGS-1.

Open with DEXTER


In the text

	Figure 6: Residuals left by the best-fit power-law model to the [21-22] Å  RGS-1 spectrum of the Crab ( upper panel). In the lower panel we show the relative RGS-1 effective area.
Open with DEXTER


In the text

	Figure 7: Residuals left by the best-fit power-law model to the [22.5-24] Å  RGS-1 spectrum of the Crab ( upper panel). In the lower panel we show the corresponding RGS-1 effective area. We did not display the residuals in the [22.9-23.6] Å  range which is affected by large instrumental features.
Open with DEXTER


In the text

Figure A.1: The RGS-1 spectrum of the ToO observation of November 14, 2003. An absorbed power-law model is not able to reproduce the data well ( left panel), while a broken power-law model fits the data better ( right panel). We fixed the absorption parameter to the Galactic value. The spectra were rebinned in order to have at least 2000 counts per bin. The other RGS spectra display similar behaviors.


In the text

Figure A.2: EPIC-PN (filled circles), RGS-1 (empty circles) and RGS-2 (crosses) spectra of Mkn 421 during the ToO observation of November 14, 2003, fitted together with a broken power-law model (with Galactic absorption value). For plotting purposes, we rebin the the RGS data to have at least 15 000 counts in each bin. The RGS spectra are significantly harder than the EPIC-PN spectrum. For clarity, we omitted the residual error bars.


In the text