Title :
Micromachined tantalum collimators for space applications
Author :
Christophersen, Marc ; Phlips, Bernard F. ; Woolf, Richard S. ; Jackson, Lori A.
Author_Institution :
U.S. Naval Res. Lab., Washington, DC, USA
Abstract :
We present the prototype-development of a tantalum X-ray collimator for AXTAR (Advanced X-ray Timing Array), a mission concept for an advanced X-ray timing experiment. The collimator is micro-fabricated in a two step process: (i) laser-machining of a hole array in Ta and (ii) chemical etching of the hole with the desired porosity (hole vs. bulk volume). The collimator design was studied by Monte Carlo simulation using GEANT4. The anticipated collimator performance shows 2 orders of magnitude rejection over 2 degrees. The angular response of the collimator was measured with an Americum-241 source and a commercial silicon detector. The prototype collimates over +/- 3 degrees.
Keywords :
Monte Carlo methods; collimators; etching; laser beam machining; porosity; silicon radiation detectors; Americum-241 source; GEANT4 using; Monte Carlo simulation; Ta hole array; X-ray collimator; advanced X-ray timing array; collimator angular response; collimator design; hole chemical etching; hole porosity; laser-machining; microfabricated collimator; micromachined tantalum collimator; silicon detector; space application; Heating; Lasers; Lenses;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE
Conference_Location :
Valencia
Print_ISBN :
978-1-4673-0118-3
DOI :
10.1109/NSSMIC.2011.6154606
