1. Gamma-ray Large Area Space Telescope SVAC ACD Variables Study (Montecarlo ) See also Francesco’s Talk Stefano Germani INFN Perugia Instrument Analysis Meeting December 9, 2005

2. SVACInstrument Analysis Meeting, December 9, 2005 Stefano Germani 2 AcdTkrIntSec Global Position AcdTkrIntSecGlobalX AcdTkrIntSecGlobalZ AcdTkrIntSecGlobalY Overlapping Tiles and Ribbons Vertical ACD Planes

3. SVACInstrument Analysis Meeting, December 9, 2005 Stefano Germani 3 AcdTkrIntSec Global Position II Tiles Ribbons Y vs X Z vs X Z vs Y Overlapping Tiles and Ribbons Crossing Ribbons on vertical plane

4. SVACInstrument Analysis Meeting, December 9, 2005 Stefano Germani 4 AcdTkrIntSecPathLength & AcdTkrIntSecArcLengthToIntSec Top Tiles with intersection well inside Tiles No PathLength smaller than Tile Thicknes

5. SVACInstrument Analysis Meeting, December 9, 2005 Stefano Germani 5 AcdTkrIntSecPathLength vs AcdTkrIntSecArcLengthToIntSec Tracker Converter BiLayer PathLength vs ArcLengthToIntSec All Tiles and Ribbons Tile 22 Top Center Tile 22 Top Center PathLength vs ArcLengthToIntSec

6. SVACInstrument Analysis Meeting, December 9, 2005 Stefano Germani 6 Conclusions We are able to explain the meaning of the ACD SVAC Variables Everything seems to be consistent with the expectations The same analysis method can be applied to the real ACD data.