XMM-Newton Science Analysis System


asmooth (asmooth-2.32.1) [xmmsas_20230412_1735-21.0.0]

Input Files

The input FITS images listed below need not be XMM images and all of them (even the mask) can be of any numeric data type output by evselect, eg int8, int16, int32, real32 or real64. All optional images (except the convolvers in inconvolversarray) must however be of the same dimensions as the inset.

1. (Mandatory) inset: the image to be smoothed.

2. (Optional) inconvolversarray: both this file and inindeximagearray are read when smoothstyle = `withset'. inconvolversarray should contain a cube or 3-dimensional array which is a stack of convolver images. The first two dimensions of the cube must be the common $x$ and $y$ dimensions of the convolver arrays; the third dimension must equal the number of convolvers. Convolvers are assigned an index which is their position (starting with 1) along the third-dimension sequence. A convolver of index $i$ is then used to smooth portions of the image for which the inindeximagearray value is also $i$.

   In the future this specification may be expanded to accommodate convolvers of varying array size.

3. (Optional) inindeximagearray: both this file and inconvolversarray are read when smoothstyle = `withset'. inindeximagearray should contain a 2-dimensional array. The values of this array after rounding to the nearest integer are taken to refer to the convolvers in the list read from inconvolversarray. The $i$th convolver in this list is then used to smooth portions of the image for which the inindeximagearray value is also $i$.

4. (Optional) intemplateset: this file is read when smoothstyle=`template'. It should contain a 2-dimensional array in the primary extension. The value of a given pixel of intemplateset is taken to be the characteristic width (sigma value) of the gaussian convolver to be used to smooth the corresponding pixel of inset. This facility doesn't offer any advantages over the smoothstyle=`withset' and I will eventually delete it.

5. (Optional) invarianceset: this file is read when readvarianceset=`true'. It should contain a 2-dimensional array in the primary extension. The array values should be the variances (ie, squares of standard deviations) in the values of inset. If the task needs these variances, but readvarianceset=`no', the task assumes that inset is Poissonian and thus can be used as an approximation of its own variance.

6. (Optional) weightset: this file is read when withweightset=`true'. It should contain a 2-dimensional array in the primary extension. The array values are used as the weights $w$ in equation 1 or 4.

7. (Optional) outmaskset: this file is read when withoutmaskset=`true'. It should contain a 2-dimensional array in the primary extension. The array values are translated to logicals by replacing values $>0$ by TRUE, the rest FALSE. The array values perform as the $\delta$ values in equation 4.

   The parameter name is now (with the abolition of the corresponding `inmask') is a little misleading and I think I'll replace it in the next version with plain `maskset'.

8. (Optional) expimageset: this file is read when withexpimageset=`true'. It should contain a 2-dimensional array in the primary extension. The array values should record the exposure of inset, if this is a well-defined quantity.