HORUS Detector Simulation Tool

HORUS (HPAD Output Response fUnction Simulator) is a detector simulation tool for modeling the relevant physical and electronic processes impacting the detective quantum efficiency of the AGIPD [1,2].

It is a collection of IDL (Interactive Data Language) routines aimed at the systematic study of the impact of certain detector design choices. IDL is a software framework developed and maintained by ITT Visual Information Solutions (http:\\www.ittvis.com).

The program is written using a modular structure, following step by step the various physical and electrical processes involved in the photon detection and signal generation process, as shown in the figure right.

The implemented models to describe the physical processes were purposely kept simple, but can be refined in future versions, if necessary. The underlying default simulation parameters are constantly updated as more data becomes available from the evaluation of the AGIPD test chips.

In particular, it was chosen not to make use of any of the classical Monte Carlo simulation tools in order to keep the tool easy to program, high simulation speed and maximum flexibility.

The detector simulation tool is part of the AGIPD project for the European XFEL and thus reflects the implementation of this detector. In the past HORUS has been successfully modified and used for simulation studies of the photon counting detector Medipix3 [3]. Currently HORUS is being adapted to the Large Pixel Detector (LPD) as part of a collaboration with the LPD consortium and the university college of London. In principle HORUS can be modified to simulate any type of integrating detector easily.

HORUS can be used both to study the overall detector performance as function of various technological choices, and to simulate the degradation of any input image in order to study its impact on the scientific application. The impact of AGIPD design choices on the data quality of XPCS experiments has already been evaluated [4]

[1] G Potdevin , U Trunk and H Graafsma, HORUS, an HPAD X-ray detector simulation program
2009 JINST 4 P09010 doi: 10.1088/1748-0221/4/09/P09010
[2] J Becker, HORUS – A detector simulation tool, XFEL seminar, 03.03.2001
[3] D Pennicard and H Graafsma, Simulated performance of high-Z detectors with Medipix3 readout 2011 JINST 6 P06007 doi: 10.1088/1748-0221/6/06/P06007
[4] Julian Becker, Christian Gutt, Heinz Graafsma, Simulation study of the impact of AGIPD design choices on X-ray Photon Correlation Spectroscopy utilizing the intensity autocorrelation technique 2011 submitted to JINST