All Figures

	Figure 1: Background subtracted MOS lightcurves of TW Hya in the energy range 0.3-1.0 keV and 1.0-2.0 keV. The panel on the bottom shows the hardness ratio computed from these bands; binsize is 1 ks.
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In the text

Figure 2: First order background subtracted XMM-Newton RGS count rate spectrum of TW Hya. Overplotted is a 3-T VMEKAL model whose parameters were derived from a combination of emission line analysis and global fitting of the medium-resolution MOS spectrum. The MOS spectrum is shown together with the same model in Fig. 4, and the best fit parameters are summarized in Table 3. Exposure time is 29 ks for each RGS. Straight horizontal lines represent gaps due to CCD chain failure or individual chip separation. Emission lines typical for stellar coronae are indicated by labels and dashed lines.

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In the text

	Figure 3: Temperature dependence of the  line ratio for neon (dotted line), oxygen (solid line), and nitrogen (dashed line) according to the CHIANTI code (Dere et al.1997). The ratios observed in the RGS spectrum of TW Hya are indicated by the shaded patterns. All observed values are compatible with a 2-3 MK hot isothermal plasma.
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In the text

	Figure 4: EPIC MOS 1 and MOS 2 spectrum of TW Hya. The data is overlaid by the best fit 3-T VMEKAL model B from Table 3; see also Fig. 2 where the same model is folded with the RGS response. The individual contributions of the two lower-temperature components and of the high-temperature component are also shown.
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In the text

	Figure 5: Close-up of the EPIC MOS 1 and MOS 2 spectrum of TW Hya in the range 5.5-12 Å: top - Model (A) from Table 3: Mg and Si abundance fixed to solar; bottom - Model (B) from Table 3: Mg and Si abundance free parameters resulting in subsolar abundances for both elements.
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In the text

	Figure 6: Comparison of photon fluxes for individual emission lines in the X-ray spectrum of TW Hya measured with the XMM-Newton RGS (see Table 2) and the Chandra HETGS-MEG (see Kastner et al.2002). The XMM-Newton and Chandra observations are separated by about one year. All lines are constant within about a factor of two.
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In the text

Figure 7: He-like triplets of Ne IX and O VII measured with the RGS together with best fit Lorentzians. The continuum close to each triplet is approximated by a straight horizontal line. The intensity enhancement to the right of the Ne IX triplet in the RGS spectrum is due to Fe XVII. But the major contamination of the Ne IX triplet is expected to come from a Fe XIX line which is unresolved from the triplet intercombination line (see text in Sect. 5.2).

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In the text

Figure 8: Temperature dependence of various line ratios measured in the RGS spectrum of TW Hya. Solid lines are CHIANTI model calculations (Dere et al.1997), shaded regions denote the  range observed with the RGS. a) - N VII /C VI ; b) - Ne IX r/O VIII ; c) - C VI /O VII r. The plots demonstrate that the C/O abundance ratio is close to solar, while the N/O and Ne/O abundance ratio can not possibly be solar.

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In the text