Table 4: Best-fit parameters of the power-law plus two Gaussians model reproducing the [21-22] Å Mkn 421 spectra taken by the RGS-1. The errorbars refer to the 90% confidence intervals.
RGS-1 [21-22.2] Å

Feature $\lambda$ FWHM k

number (Å) (mÅ) (cts cm^-2 s^-1 Å^-1)

ToO spectrum

7 $21.5915\pm0.013$ $\rm 78^{+28}_{-25}$ $-0.0025\pm0.0007$

8 $21.801\pm0.0005$ $7\pm1$ $-0.018\pm0.005$

Archival data

7 $21.612\pm0.010$ $\rm 68^{+19}_{-16}$ $-0.012\pm0.002$

8 $21.819\pm0.001$ $12\pm2$ $-0.342\pm0.068$

Total

7 $21.603\pm0.008$ $\rm 81^{+17}_{-15}$ $-0.109\pm0.019$

8 $21.823\pm0.001$ $6\pm2$ $-0.277\pm0.059$

**Table 4:** Best-fit parameters of the power-law plus two Gaussians model reproducing the [21-22] Å Mkn 421 spectra taken by the RGS-1. The errorbars refer to the 90% confidence intervals.
RGS-1 [21-22.2] Å
Feature	$\lambda$	FWHM	k
number	(Å)	(mÅ)	(cts cm^-2 s^-1 Å^-1)
ToO spectrum
7	$21.5915\pm0.013$	$\rm 78^{+28}_{-25}$	$-0.0025\pm0.0007$
8	$21.801\pm0.0005$	$7\pm1$	$-0.018\pm0.005$
Archival data
7	$21.612\pm0.010$	$\rm 68^{+19}_{-16}$	$-0.012\pm0.002$
8	$21.819\pm0.001$	$12\pm2$	$-0.342\pm0.068$
Total
7	$21.603\pm0.008$	$\rm 81^{+17}_{-15}$	$-0.109\pm0.019$
8	$21.823\pm0.001$	$6\pm2$	$-0.277\pm0.059$

Source LaTeX | All tables | In the text

	1 Introduction
	2 The XMM-Newton observations and data reduction
	3 Looking for lines in various segments of the spectra
	4 Discussion
	5 Conclusions
	References
	Online Material
	Appendix A: RGS spectral analysis and comparison with EPIC-PN