XMM Users' Handbook


next up previous contents
Next: Two types of EPIC Up: XMM - a concise Previous: Straylight rejection

   
EUROPEAN PHOTON IMAGING CAMERA (EPIC)


Principal Investigator: Dr. M. J. L. Turner, Leicester University



Two of XMM's X-ray telescopes are equipped with EPIC MOS (Metal Oxide Semi-conductor) CCD arrays, the third carries a different CCD camera called EPIC pn. In a nutshell, the XMM EPIC cameras offer the possibility to perform extremely sensitive imaging observations over a field of view of 30' and the energy range from 0.1 to 15 keV, with moderate spectral ( $E/\Delta E \sim 20-50$) and angular resolution (6'' FWHM; 15'' HEW). The pn type camera can be operated with very high time resolution (down to 0.03 ms in the timing mode, albeit with a very low duty cycle).



  
Figure 15: The field of view of the two types of EPIC cameras; EPIC MOS (left) and EPIC pn (right). The shaded circle depicts a 30' diameter area. For the alignment of the different cameras with respect to each other in the XMM focal plane refer to the text.
\begin{figure}
\begin{center}
\leavevmode
\epsfig{width=1.0\hsize, file=figs/epic_FOV.ps}
\end{center} \end{figure}

The detector layout and the baffled X-ray telescope FOV of both types of EPIC cameras are shown in Fig. 15. In both cases the sensitive area of the detector is about 30' across. Note that Fig. 15 is just a rough sketch. It does not show details, such as:

All EPIC CCDs operate in photon counting mode, producing event lists.1 This allows for simultaneous imaging and non-dispersive spectroscopy due to the intrinsic energy resolution of the pixels.


Note: If for any reason a user should decide to observe a target with EPIC not on-axis, but instead off-axis, for off-axis angles in excess of 2.5' the RGS spectrum might slip off the detector array (because the RGS FOV is about 5' across in the cross-dispersion direction).



 
next up previous contents
Next: Two types of EPIC Up: XMM - a concise Previous: Straylight rejection
European Space Agency - XMM Science Operations Centre