Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://xmm.vilspa.esa.es/docs/documents/CAL-SRN-0222-1-1.ps.gz Äàòà èçìåíåíèÿ: Mon Nov 6 12:15:58 2006 Äàòà èíäåêñèðîâàíèÿ: Mon Oct 1 22:44:19 2012 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: ï ï ï ï ï ï ï ï ï ï ï ï ï ï

XMM­Newton CCF Release Note
XMM­CCF­REL­222
Update of EPIC MOS2 gain epoch revs. 446­533
Martin Stuhlinger, Darren Baskill
October 31, 2006
1 CCF components
Name of CCF VALDATE EVALDATE List of Blocks CAL XSCS
(start of val. period) (end of validity period) changed VERS. flag
EMOS2 ADUCONV 0042 2002­05­16T05:00:01 2002­11­07T05:00:00 OFFSET GAIN NO
1

XMM­Newton CCF Release XMM­CCF­REL­222 Page: 2
2 Changes
The new MOS2 ADUCONV CCF issue 42 has been created together with a MOS2 CTI CCF issue
30. This new CCF replaces the previous MOS2 ADUCONV CCF issue 36 (see XMM­CCF­REL­
207) and covers the same time period 2002­05­16 to 2002­11­07 (revs. 446­533).
Using CCF EMOS2 CTI 0024.CCF it was found that low energy images of MOS2 CCD4 were
incomplete; high RAWX columns were not present in the images. There was also a RAWX/PI
dependence --- as the upper PI selection threshold was lowered the area of blank CCD increased
(see XMM­CCF­REL­221 for details). Beside of this low energy cut­o#, the interaction of CTI
and ADUCONV parameters took care that the energy reconstruction of the events were correct.
The energy positions of the internal calibration lines were accurate by better than 5 eV at Al­K
and Mn­K. The replacement of EMOS2 CTI 0024.CCF necessitates an update of the corresponding
ADUCONV CCF.
These new gain parameters have been tuned to suppress the residuals present in the energy
scale using the old CCFs. The replacement CCFs, as with their previous versions, assume a linear
relationship between the charge deposited inside a pixel and the energy of the detected X--ray:
E eV = gain âE charge + o#set
The new gain and o#set values have been calculated from observations of the on­board calibration
sources, which o#er three spectral lines: Al K# at 1486.57 eV (Suresh et al 2000, J. Phys. B. At.
Mol. Opt. Phys. 33), Mn K# at 5895.75 eV and Mn K# at 6489.97 eV (Holzer et al 1997, Phys.
Rev. A, 56, 6). The derived gain and o#set values used in each CCF are averaged values taken from
the calibration observations made during the corresponding CCF time period. Starting at rev. 918,
the MOS calclosed observations are performed during slews. For the analyses, several slew calclosed
observations were combined to achieve reasonable statistics.
However, observations during eclipse seasons have been neglected, since the cooler EPIC MOS
Analogue Electronics (EMAE) require a smaller gain correction. This e#ect is most notable in the
calibration observations, since these were performed immediately after the end of the eclipses; by
the time science observations commence, the EMAE has returned to its nominal temperature and
so this temperature variation during eclipse has no impact on science observations.
Calculating the linear gain term, further spurious points that deviate from the mean value by
more than 5 times the average error of the points are also rejected; such rejection is not required
for the constant o#set term.
3 Scientific Impact of this Update
For all CCDs and all time periods, the energy scale is now reconstructed to about 5 eV or better
for the entire energy range. The improvement of this new gain on existing data is expected to be
less than 5­10 eV at 6 keV, and less than 5 eV at 1.5 keV.
The new EMOS2 ADUCONV 0042.CCF was released together with the new EMOS2 CTI 0030.CCF

XMM­Newton CCF Release XMM­CCF­REL­222 Page: 3
(see XMM­CCF­REL­221), since the new cti with old gains, and old cti with new gains may give
unexpected results!
4 Estimated Scientific Quality
CCD4 shows a slight enhanced o#set of up to 7 eV at higher energies (6 keV). As the calibration
team is currently working on an update of the complete CTI/ADUCONV CCFs sets, this small
o#set (about 1 per mill) of an outer CCD is accepted by the calibration team.
The energy scale accuracy is better or about 5 eV (except CCD4) on the whole energy range for
i) not too bright sources and ii) outside of eclipse seasons (at the start of revolutions). In this two
cases, as explained in XMM­CCF­REL­124, the energy scale can be significantly over­corrected.
5 Test procedures & results
The new ADUCONV CCFs have been tested with the SASv7.0. No RAWX/PI dependence in low
energy images was found any more. The results for the energy positions of the internal calibration
lines using the new CCF are presented in Fig. 1 to Fig. 2.
6 Expected Updates
The calibration team is currently working on a column dependent CTI which can take into account
di#erent CTI behaviour of the individual columns as well as di#erent behaviour of sections within
a single column. These new set of CTI CCFs will also require an update for the ADUCONV CCFs
for all epochs.

XMM­Newton CCF Release XMM­CCF­REL­222 Page: 4
Figure 1: MOS2 Al K # line energy scale using the new EMOS2 ADUCONV 0042.CCF. Eclipse
seasons are indicated by vertical blue lines, CCF epochs by red lines. The horizontal solid line
represents the laboratory line energy, the dotted lines the ±5 eV deviations.

XMM­Newton CCF Release XMM­CCF­REL­222 Page: 5
Figure 2: MOS2 Mn K # line energy scale using the new EMOS2 ADUCONV 0042.CCF. Eclipse
seasons are indicated by vertical blue lines, CCF epochs by red lines. The horizontal solid line
represents the laboratory line energy, the dotted lines the ±5 eV deviations.