We use a deep XMM-Newton Reflection Grating Spectrometer observation to examine the X-ray emission from the core of the Centaurus cluster of galaxies .
We clearly detect Fe xvii emission at four separate wavelengths , indicating the presence of cool X-ray emitting gas in the core of the cluster .
Fe ions from Fe xvii to xxiv are observed .
The ratio of the Fe xvii 17.1Å lines to 15.0Å line and limits on O vii emission indicate a lowest detected temperature in the emitting region of 0.3 to 0.45 keV ( 3.5 to 5.2 \times 10 ^ { 6 } K ) .
The cluster also exhibits strong N vii emission , making it apparent that the N abundance is supersolar in its very central regions .
Comparison of the strength of the Fe xvii lines with a Solar metallicity cooling flow model in the inner 17 kpc radius gives mass deposition rates in the absence of heating of 1.6 - 3 \hbox { $ \hbox { $ \thinspace M _ { \odot } $ } \thinspace yr ^ { -1 } $ } .
Spectral fitting implies an upper limit of 0.8 \hbox { $ \hbox { $ \thinspace M _ { \odot } $ } \thinspace yr ^ { -1 } $ } below 0.4 keV , 4 \hbox { $ \hbox { $ \thinspace M _ { \odot } $ } \thinspace yr ^ { -1 } $ } below 0.8 keV and 8 \hbox { $ \hbox { $ \thinspace M _ { \odot } $ } \thinspace yr ^ { -1 } $ } below 1.6 keV .
The cluster contains X-ray emitting gas over at least the range of 0.35 to 3.7 keV , a factor of more than 10 in temperature .
We find that the best fitting metallicity of the cooler components is smaller than the hotter ones , confirming that the apparent metallicity does decline within the inner 1 arcmin radius .