Correcting spatial inhomogeneities
of the absolute energy scale
EPIC Calibration & Operations Meeting
Madrid, 2010 March 23-24
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Correcting spatial inhomogeneities of the absolute energy scale
1. offsets in the energy scale due to errors in the offset map
2. column gain variations after launch
3. CTI changes due to residual light through the ventilation hole
EPIC-Cal Meeting, MPE-Garching, Germany, 2006 May 4
20 adu image, rev 546
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Correcting spatial inhomogeneities of the absolute energy scale
1. offsets in the energy scale due to errors in the offset map
2. column gain variations after launch
3. CTI changes due to residual light through the ventilation hole
EPIC-Cal Meeting, Mallorca, Spain, 2007 Nov 6-7
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Correcting spatial inhomogeneities of the absolute energy scale
1. offsets in the energy scale due to errors in the offset map
2. column gain variations after launch
3. CTI changes due to residual light through the ventilation hole
EPIC-Cal Meeting, Mallorca, Spain, 2007 Nov 6-7
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Correcting spatial inhomogeneities of the absolute energy scale
1. offsets in the energy scale due to errors in the offset map
2. column gain variations after launch
3. CTI changes due to residual light through the ventilation hole
EPIC-Cal Meeting, Mallorca, Spain, 2009 March 31 – April 1
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Vela SNR: extended source
with bright OVII emission
 excellent calibration source
2001- 2007: 12 long FF observations,
several with different pointing
coordinates and roll angles
 fairly homogeneous illumination of
the detector
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Superposition
of all Vela SNR
observations in
FF mode
0.40 – 0.74 keV
photon map (singles)
exposure map
maximum: 172 singles/pixel
total exposure (after removing
times of background flares):
~300 ks
exposure corrected map
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Internal calibration source onboard XMM-Newton / EPIC-pn
Al-K
Mn-K
inhomogeneous irradiation at Mn-K, illumination of quadrant 3 very poor
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Superposition
of all Vela SNR
observations in
FF mode
0.40 – 0.74 keV
photon map (singles)
exposure map
maximum: 172 singles/pixel
total exposure (after removing
times of background flares):
~300 ks
exposure corrected map
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Spatial properties of the absolute energy scale
0.40 – 0.74 keV
photon map
(singles)
 adaptive
binning into
subareas of
similar signal
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Spatial properties of the absolute energy scale
vertical binning
according to response
matrices
horizontal binning
adaptively, criterion:
~5000 single events
within 400 – 740 eV
(above background)
 422 fields
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Preparations for a joint fit
removal of periods of enhanced background
correction for local energy shifts due to errors in the offset map (epreject)
correction for energy shifts between the individual observations
correction for out-of-time events
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Spectral model used ( E = 0.43 – 0.74 keV )
all line energies and widths coupled to reference line (O VII r)
relative line fluxes of O VII triplet fixed
8 fit parameters
continuum approximated by powerlaw
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Spectral model used ( E = 0.43 – 0.74 keV )
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
result:
energy scale
spatially
homogeneous
within ±10 eV
however, also
evidence for
systematic shifts
in a ring-like
pattern
mean 1σ error in
line energy: 1.8 eV
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Preparations for a joint fit
removal of periods of enhanced background
correction for local energy shifts due to errors in the offset map (epreject)
correction for energy shifts between the individual observations
correction for out-of-time events
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Preparations for a joint fit
removal of periods of enhanced background
correction for local energy shifts due to errors in the offset map (epreject)
correction for energy shifts between the individual observations
correction for out-of-time events
default in SAS:
PI binned with
5 eV resolution
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Preparations for a joint fit
removal of periods of enhanced background
correction for local energy shifts due to errors in the offset map (epreject)
correction for energy shifts between the individual observations
correction for out-of-time events
special switch
in SAS:
PI binned with
1 eV resolution
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
“before”:
5 eV resolution
in PI correction
54 dof
0.43 – 0.74 keV
mean 1σ error in
line energy: 1.8 eV
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
“after”:
1 eV resolution
in PI correction
59 dof
0.40 – 0.74 keV
mean 1σ error in
line energy: 1.6 eV
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merged Vela SNR observations (flag = 0, pattern = 0)
original data
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merged Vela SNR observations (flag = 0, pattern = 0)
after applying the
energy corrections
(same binning!)
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merged Vela SNR observations (flag = 0, pattern = 0)
after applying the
energy corrections
(different binning!)
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Al-K (calclosed exposure in rev 0080):
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Al-K (calclosed exposure in rev 0080):
“before”
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Al-K (calclosed exposure in rev 0080):
“after”
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Mn-K (calclosed exposure in rev 0080):
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Mn-K (calclosed exposure in rev 0080):
“before”
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Applying the energy shifts derived from Vela observations
to Mn-K (calclosed exposure in rev 0080):
“after”
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: the “front side”
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped and enlarged
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
pn: “front
side”,
image
flipped
and enlarged
EPICEPIC
pn: “front
side”,
image
flipped,
enlarged
and rotated
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped, enlarged and rotated
CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped, enlarged and rotated
CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped, enlarged and rotated
CCD 4
Ge-L, CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”, image flipped, enlarged and rotated
CCD 4
Ge-L, CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn: “front side”,
flipped,
enlarged and rotated
EPICimage
pn ground
calibration
CCD 4
Ge-L, CCD 4
Ge-L
CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn ground calibration
Fe-K
CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
EPIC pn ground calibration
Ge-K
CCD 4
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Deviations from spatially constant (but energy dependent) CTI per column
(EPIC pn ground calibration at Orsay)
~ 1.3 % (15 eV)
~ 0.4 % (25 eV)
~ 0.35 % (35 eV)
EPIC pn ground calibration: no CTI maps at all below 0.7 keV (Fe-L)
no good CTI maps below 1.2 keV (Ge-L)
good CTI maps at 1.2 keV (Ge-L), 6.4 keV (Fe-K), 8.0 keV (Cu-K), 9.9 keV (Ge-K)
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Deviations from spatially constant (but energy dependent) CTI per column
(EPIC pn ground calibration at Orsay)
OVII 0.57 keV
~ 1.8 % (10 eV)
~ 1.3 % (15 eV)
~ 0.4 % (25 eV)
~ 0.35 % (35 eV)
EPIC pn ground calibration: no CTI maps at all below 0.7 keV (Fe-L)
no good CTI maps below 1.2 keV (Ge-L)
good CTI maps at 1.2 keV (Ge-L), 6.4 keV (Fe-K), 8.0 keV (Cu-K), 9.9 keV (Ge-K)
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Merging ground and in-orbit
CTI determinations ..
.. to be continued ..
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23
Correcting spatial inhomogeneities
of the absolute energy scale
EPIC Calibration & Operations Meeting
Madrid, 2010 March 23-24
EPIC Calibration Meeting, Madrid
Correcting spatial inhomogeneities of the absolute energy scale
K. Dennerl, 2010 March 23