XMM-Newton SAS Home Page
XMM-Newton Science Analysis System

bkgfit (ebkgmap-2.10.1) [xmmsas_20211130_0941-20.0.0]


This section documents the parameters recognized by this task (if any).

ParameterMand Type Default Constraints
The name of the Poissonian image which it is desired to fit background to.
fitsetsyesdataset list  
List of names of datasets, each of which is an image which represents one of the components of the background model to be fitted.
If fitstyle=`whole', the pixels of poissonset may have any value, and a standard Poisson distribution is assumed. If fitstyle=`base', only pixels which have values below a truncation level are included in the fit: in this case the probability distribution is necessarily a (renormalized) Poisson distribution which extends only from zero to the truncation level. The second type of fit is useful if there are bright patches on the image which it is desired to exclude.
This parameter is read if fitstyle=`base'. It should point to a dataset which has in its primary extension an image, of the same pixel dimensions as poissonset, fitsets or any other image input to the task. The task interprets this as an image of cutoff values: only those pixels of poissonset which have values below the corresponding value of truncationset will be fitted to the task; the probability distributions at those pixels being similarly truncated.
If `yes', the task reads the name of a mask image from maskset. Only unmasked pixels (that is, pixels for which the mask evaluates to TRUE) are fitted.
The name of the mask image dataset.
If `yes', the task reads starting values of the amplitudes $\mathbf{a}$ from initcoeffs. If withinitcoeffs=`no', the task estimates these itself.
initcoeffsnoreal list1.0 
A list of starting values of the amplitudes $\mathbf{a}$. This is only read if withinitcoeffs=`yes'. There must be the same number of elements in this list as in fitsets.
The name of the output image dataset.
ParameterMand Type Default Constraints

XMM-Newton SOC -- 2021-11-30