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**Figure F.6:** Electronic position correction tables for PSPC-C:
left from top to bottom ,
, and , according to
Eq.(F.8);
right from top to bottom ,
, and , according to
Eq.(F.9).
The recorded raw detector coordinates and
correspond to `RAWX` and `RAWY` in the figure.

**Figure F.7:** Electronic position correction tables for PSPC-B:
left from top to bottom ,
, and , according to
Eq.(F.8);
right from top to bottom ,
, and , according to
Eq.(F.9).
The recorded raw detector coordinates and correspond to
`RAWX` and `RAWY` in the figure.

The PSPC wires cause small-scale spatial non-linearities. This effect depends on the position as well as on the energy of the photon. A correction vector is computed using a parabola with spatially-dependent coefficients and the amplitude as variable according to Eq. (F.8) and (F.9).

Here , , and are the correction coefficients parallel
to the anode wire direction while , , and denote
coefficients perpendicular (*``senkrecht''*) to the anode wires.
The correction coefficients are stored in table with 4000 elements
and the electronic position correction is actually done by interpolation
between two table elements
(*cf.* Eq. (F.11)).

Figure F.6 and F.7 shows this correction for PSPC-C and PSPC-B, respectively.

There is an inconsistency in the documentation about the amplitude
to be used in the correction:
[Hasinger and
Snowden1990]
as well as
Chap. 3
and
[Turner et al.1995]
state , whereas
Chap. 8
(SASS) uses .
In fact, in the creation of the correction tables *no* corrections
had been applied, *i.e., * should be used; however, the differential
effect between and is minor
[Briel1995].

**Parameters:**

- ] raw detector
- pulse height of event, corrected for ADC non-linearity
- tables for electronic position correction; dimension 4000 (Figs. F.6 and F.7, interpolated)
*r*- random number (real number in [0.0,1.0])
- detector
*x*coordinate (electronic position correction applied)

The electronic position correction in *y* is done similiar to the
correction in *x*; simply replace *x* by *y* in the above formulae.

**Remarks:**

**SASS source code:**
package `PSPC`, bubble `CT`, subroutine `DCORE`

**SASS files:**

`p$manpar:senk_c.dat`- correction tables for
*y*direction (PSPC-C) (Fig. F.6) `p$manpar:para_b.dat`- correction tables for
*x*direction (PSPC-B) (Fig. F.7) `p$manpar:senk_b.dat`- correction tables for
*y*direction (PSPC-B) (Fig. F.7)

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