XMM-Newton Science Analysis System


ssclib (ssclib-4.30) [xmmsas_20160201_1833-15.0.0]

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instToRaw

  interface instToRaw
    subroutine instToRawScalarInt16(rawX, rawY, detX, detY, thetaArcsec, phi)
      real(single),   intent(in),  optional :: detX,&
                                               detY
      real(double),   intent(in),  optional :: thetaArcsec,&
                                               phi
      integer(int16), intent(out)           :: rawX,&
                                               rawY
    end subroutine instToRawScalarInt16

    subroutine instToRawVectorInt16(rawX, rawY, detX, detY, thetaArcsec, phi)
      real(single),   intent(in),  optional :: detX(size(rawX)),&
                                               detY(size(rawX))
      real(double),   intent(in),  optional :: thetaArcsec(size(rawX)),&
                                               phi(size(rawX))
      integer(int16), intent(out)           :: rawX(:),&
                                               rawY(size(rawX))
    end subroutine instToRawVectorInt16

    subroutine instToRawScalarReal32(rawXreal, rawYreal, detX, detY&
      , thetaArcsec, phi, isOffChip)

      real(single),  intent(in),  optional :: detX,&
                                              detY
      real(double),  intent(in),  optional :: thetaArcsec,&
                                              phi
      real(single),  intent(out)           :: rawXreal,&
                                              rawYreal
      logical(bool), intent(out), optional :: isOffChip
    end subroutine instToRawScalarReal32

    subroutine instToRawVectorReal32(rawXreal, rawYreal, detX, detY&
      , thetaArcsec, phi, isOffChip)

      real(single),  intent(in),  optional :: detX(size(rawXreal)),&
                                              detY(size(rawXreal))
      real(double),  intent(in),  optional :: thetaArcsec(size(rawXreal)),&
                                              phi(size(rawXreal))
      real(single),  intent(out)           :: rawXreal(:),&
                                              rawYreal(size(rawXreal))
      logical(bool), intent(out), optional :: isOffChip(size(rawXreal))
    end subroutine instToRawVectorReal32
  end interface

These subroutines convert to chip coordinates (ie, the RAWX/Y or PIXCOORD1 system) from instrument-centric coordinates, the latter being either the DETX/Y (the same, up to a scalar multiple, as the CAMCOORD2 system) or the TELCOORD system, depending on which of the optional variables $detX$, $detY$, $thetaArcsec$ and $phi$ the caller has supplied.

The `int16' routines employ the cal calls CAL_camCoord1ToChipCoord and CAL_chipCoordToPixCoord1. However, these calls have two drawbacks: firstly, they return integer values, and secondly, they are only valid `on-chip'. However there are occasions when it is desirable to obtain finer precision in the chip coordinates and also to be able to out of the strict range. For this reason I wrote the `real32' routines. The latter do not use the cal calls mentioned above. Instead they first move forward by calculating the instrument-centric coordinates of the corners of the CCD; this information is then iused to perform a linear back-transformation of the input instrument-centric coordinates. The logical variable $isOffChip$ is also set.

NOTE this subroutine requires the cal to have been set to the correct instrumentId, ccdChipId and (if instrumentId is EMOS1 or EMOS2) ccdNodeId before the call.