XMM-Newton Science Analysis System


eootepileupmask (ebkgmap-2.10.2) [xmmsas_20230412_1735-21.0.0]

Behaviours and command-line arguments.

This task reads an event file as an input, estimating the piled up pixels, and outputs either the sky coordinate image or 3-dimensional chipcube (controlled by outputstyle).

In short, we recommend to specify and the sky coordinate image as an output, of which the reasons are described below.

1. if the output is the chipcube, the process runs as follows:
   The task calculates the normalised count-per-frame-per-pixel (=rate) map for each chip, taking account of the energy (PI) of each event. Then when a pixel is found to show a rate exceeding the given threshold, the entire row along either or both X and/or Y-axis of the pixel is masked depending whether the areas of OOTE events and/or RGA spikes are specified to be masked or not, and it is output.

2. if the output is the sky-coordinate image, the process runs as follows:
   The core of the routine is exactly the same as the above case. However, the coordinate conversion into sky-coordinates is not a trivial job, as the pile-up phenomenon is basically processed on the chip(raw) coordinates. Hence a user is allowed to specify the binned-attitude file. If this (binnedattset) is set, the task splits the event files into the given time bins (described in the file binnedattset), performs the above-described calculation (of the normalised rate map) for each of these time bin, converts each normalised rate map and mask map into the sky coordinates. Finally the task calculate the logical sum of the mask file. In other words, all the pixels that experience the rate above the threshold in one of the time bin are masked. Note that frames with too short duration are not used in this calculation of rate and mask images (Controlled by avcnttoprocess) in this case. If a user specifies so (controlled by attstyle), the entire observation is used as one set — in that case, the spatial fluctuation of the spacecraft is not taken into account (the median attitude value is simply used for the coordinate conversion).