g-2 Tracker Electronics: Design Outline

1. g-2 Tracker Electronics:Design Outline

2. General Overview • The experiment has a tracker made from mylar straws which detect charged particles as they pass through. • The ionisation signal from the straws is processed by ASDQs which are ASICs that are used for shaping/amplifying • The ASDQ sends digital LVDS to an FPGA acting as a TDC to give us timing (and therefore position) information. • In our baseline design, the ASDQ boards attach directly to the straws inside our vacuum chamber. • In this scenario we’d likely need to use flex circuits to bring the digital signals from the ASDQs to the TDCs outside the vacuum. 2

3. Tracker Stations Tracker Station (3 in total) Tracker modules 3

4. Tracker Module 4

5. Electronics layout: top-view cartoon TDC Board ASDQ Board Cable for illustration only HV supplied to end board & passed down with jumper wires • Only one cable shown here, but we’ll need four for this largest manifold. 5

6. Flex circuits: what might we need? 6

7. Electronics layout: front-view cartoon TDC Boards ASDQ Boards Flex circuit? Straws 7

8. Electronics layout: section thru’ manifold • Even with very thin flex circuit, we’re still very tight on space here. Water cooling Flexi-circuit (0.3 mm) Mylar (for HV clearance) 15 mm 58 mm 8

9. A possible feedthrough option? • One way to get signals out may be to use a circuit board as a feedthrough: Flange opening Manifold Connect directly to TDC board Flex Circuit Connectors (top & bottom) Epoxy Feedthrough board TDC board 9

10. An alternative design: • We could move ASDQs outside the manifold and bring out analogue signals (saves power and space inside manifold). • Is this a possibility with flexicable or do we need to stick with twinaxial individually shielded pairs to keep our small signals in good shape? Alternative Design Baseline Design Digital signals to outside manifold Manifold End 10