Implementation of a FLUKA simulation of a Timepix device for
                        space dosimetry applications.

                              John Idarraga
                          University of Houston

Abstract:
The timepix chip is a 256x256 pixel array with independent electronics for each
pixel channel.  With a pitch of 55um in both X and Y the net area is about 2.0
cm^2.  In adition to the readout chip, typically a planar sensor with different
thicknesses: 300um, 500um or 1000um, is used as the active material.  This
assembly has proven to be of practical use in dosimetry applications.  In this
particular case its use in space dosimetry where heavy ions are present
delivering dose equivalent measurements with great quality factors is our
subject of study.  The challenges for the simulation project are many. Between
others: i) the implementation of such a structure in great detail and the
correct determination of the LET with beams up to iron, ii) understant the
detector efficiency and iii) connect appropiately the sensor and electronics
effects.  The use of this device as a neutron detector using convertion layers
on top of the sensor will also be studied in simulation.