XMM-Newton Users Handbook Filter choice

It is considered important to take advantage of the unique capabilities of OM in the ultraviolet domain, and therefore the recommendation is to use:

  1. UVM2 (first choice)
  2. UVW1 (second choice)
  3. U (third choice)

Although the UVW2 reaches further in the UV, its use is not encouraged because of its low in-flight performance.

A different set of filters for observations in the OM default configurations may be chosen, based on scientific considerations. However, the sequence in which the filters are used must follow their order in the filters wheel (see § 3.5.3). For example, the three filters listed above have to be set in the sequence U, UVW1 and UVM2.

European Space Agency - XMM-Newton Science Operations Centre