1. Background in the CILD01fw Weekly Detector Meeting May 5, 2009 André Sailer CLIC_01_ILD

2. Content Further changes to the ILD Detector –Vertex Detector –Changes to CILD_01 Magnetic Field: 4 Tesla Almost pure Tungsten in HCal Background in the Tracking Detectors –“Add-ons” to the Software –Updates to first Results

3. New Radius for Vertex Detector Inner Radius of Beampipe moved to 3cm Double Layers –At: 31, 44, 58 mm –Not optimized for anything Detector Model: CILD_01fw

4. Background in Detector Right now: –Only Looking at Incoherent Pairs –Limited Statistics (<1 BX, 300k particles) –“Proof of Principle” Want to know: –how much Background there is –where it is coming from Using: –Mokka, Marlin (for reading LCIO files)

5. Where is the Background coming from? Incoherent Pairs coming from Vertex –But they can backscatter into the Tracking Detectors –Standard Mokka Trackers in most cases only save the Parent Particle (coming from the IP) –Add sensitive Layers in front of possible backscatter origins: LumiCal, BeamCal, Final Focus Quadrupole (QD0) Made parts of the beam pipe sensitive

6. Sensitive Layers Only thin sheets of surrounding Material (Air) –Not changing the physics in the simulation –Just a point for Mokka to write out all particles that pass through –Well maybe sometimes the parent of the particles is attributed to the hit (not sure)

7. Hits in the Tracking Detectors From: A. Savoy ‐ Navarro, TILC09

8. Projections (New)

9. Hits in the Tracking Detectors All the hits in the Tracking Detectors caused by the Incoherent Pairs Colored Points show, where the Background came from supposedly Identification of Source using all generations back to the first particle

10. Hits in the Tracking Detectors All the hits in the Tracking Detectors caused by the Incoherent Pairs Colored Points show, where the Background came from supposedly Identification of Source using all generations back to the first particle

11. Origins of the Hits

12. Identification not Perfect Here the “Vertex” of the particles causing the hits are shown E.g.: Some Particles originating near BeamCal (QD0) are not attributed to it Good Thing: Some Particles from IP are Identified to have hit LCal etc. Using parent particles almost all particles seem to be correctly attributed to their origin

13. Identification not Perfect Here the “Vertex” of the particles causing the hits are shown E.g.: Some Particles originating near BeamCal (QD0) are not attributed to it Good Thing: Some Particles from IP are Identified to have hit LCal etc. Using parent particles almost all particles seem to be correctly attributed to their origin

14. Projections

15. Stacked

16. When do the Hits occur Some Hits caused by particles directly coming from IP Second wave from Backscatters Agrees with identification of source

17. Hits in the VXD Some 700 Hits in the inner Double Layer Roughly 0.02 hits per mm² and BX Were less hits for the 4 Tesla simulation

18. With and Without Graphite

19. That’s all!

20. Projections (old)