1. L. Greiner1PXL Sensor and RDO review – 06/23/2010 STAR Heavy Flavor Tracker Overview With parameters pertinent to the PXL Sensor and RDO design

2. L. Greiner2PXL Sensor and RDO review – 06/23/2010 STAR Pixel Sensor and Electronics Group LBNL Leo Greiner, Howard Matis Thorsten Stezelberger, Xiangming Sun, Michal Szelezniak, Chinh Vu, Howard Wieman UTA Jo Schambach IPHC Strasburg Marc Winter CMOS group

3. L. Greiner3PXL Sensor and RDO review – 06/23/2010 STAR Talk Outline PXL in HFT - goals and parameters that provide bounds on the sensor and RDO requirements. PXL environment. Sensor requirements based on goals and environment. RDO requirements and design. Development path for Sensors and RDO. Summary. The primarily focus of this talk is technical. Physics and simulations are outside of the scope of the review and discussed only to provide background for requirements.

4. L. Greiner4PXL Sensor and RDO review – 06/23/2010 STAR STAR Detector at RHIC

5. L. Greiner5PXL Sensor and RDO review – 06/23/2010 STAR Physics Goals Direct Topological reconstruction of Charm Detect charm decays with small c , including D 0  K  Method: Resolve displaced vertices (100-150 microns)

6. L. Greiner6PXL Sensor and RDO review – 06/23/2010 STAR Inner Detector Region Upgrades Graded resolution: TPC→SSD → IST → PXL ~1mm ↘ ~300µm ↘ ~250µm ↘ <30µm TPC – Time Projection Chamber (main detector in STAR) HFT – Heavy Flavor Tracker SSD – Silicon Strip Detector IST – Inner Silicon Tracker PXL – Pixel Detector (PIXEL) Tracking Inward

7. L. Greiner7PXL Sensor and RDO review – 06/23/2010 STAR PXL Detector Ladder with 10 MAPS sensors (~ 2×2 cm each) Mechanical support with kinematic mounts Cabling and cooling infrastructure Detector extraction at one end of the cone New beryllium beam pipe (800 µm thick, r = 2 cm)‏ 2 layers 10 modules 4 ladders/module

8. L. Greiner8PXL Sensor and RDO review – 06/23/2010 STAR Tracking Requirements -1 ≤ Eta ≤ 1, full Phi coverage (TPC coverage) ≤ 30 µm DCA pointing resolution required Two or more layers with a separation of > 5 cm. Pixel size of ≤ 30 µm Radiation length as low as possible but should be ≤ 0.5% / layer (including support structure). The goal is 0.37% / layer ~200-300 hits / sensor* (4 cm 2 ) in the integration time window (at operating point chosen). * at r=2.5 cm These tracking requirements and all following parameters have been established through simulation studies that have chosen an optimized operating point for the PXL detector through multi-parameter analysis of the entire upgrade system.

9. L. Greiner9PXL Sensor and RDO review – 06/23/2010 STAR PXL Tracking Environment Charged particle density (at L = 8 x 10 27 cm -2 s -1 ) for a 200 µs integration time is: 63 hits / cm 2 at r = 2.5 cm (includes peripheral collision electrons) 6 hits / cm 2 at r = 8.0 cm Radiation environment: 20 to 90 kRad and 2 * 10 11 to 10 12 1 MeV n eq cm -2 year -1

10. L. Greiner10PXL Sensor and RDO review – 06/23/2010 STAR Mechanically Driven Constraints Detector physical geometry and segmentation. Sensor power dissipation (air cooling) Radiation length budget dedicated to cable/sensor assembly (0.17%) Number of sensors / ladder Contributes to: Radiation load (r = 2.5 cm) Fine twisted pair wire interface to ladders

11. L. Greiner11PXL Sensor and RDO review – 06/23/2010 STAR PXL Sensor Requirements Sensor requirements (consistent with IPHC development direction) ~2 cm x 2 cm (1 reticle) size. Pixel size ≤ 30 µm. Integration time of ≤ 200 µs for L = 8 x 10 27 cm -2 s -1 Power dissipation ≤ 170 mW/cm 2 (air cooling) Binary output with remote threshold adjustment Efficiency of ≥ 95% for MIPs with a simultaneous accidental noise rate of ≤ 10 -4 Maintain efficiency and accidental rate after radiation exposure of 90 kRad and 10 12 1 MeV n eq / cm 2. ≤ 4 LVDS output channels per sensor (ladder space) Remote configuration

12. L. Greiner12PXL Sensor and RDO review – 06/23/2010 STAR PXL Attributes Pointing resolution (12  19GeV/p  c)  m LayersLayer 1 at 2.5 cm radius Layer 2 at 8 cm radius Pixel size 18.4  m X 18.4  m Hit resolution 8  m Position stability 6  m rms (20  m envelope) Radiation length per layerX/X 0 = 0.37% Number of pixels436 M Integration time (affects pileup) 0.2 ms Radiation requirement20 to 90 kRad 2*10 11 to 10 12 1MeV n eq/cm 2 Rapid detector replacement< 8 Hours

13. L. Greiner13PXL Sensor and RDO review – 06/23/2010 STAR RDO Infrastructure Requirements In addition to the detailed requirements imposed by the interface to the sensors, the RDO system shall: Triggered detector system fitting into existing STAR infrastructure (Trigger, DAQ, etc.) Deliver full frame events to STAR DAQ for event building at approximately the same rate as the TPC (1 kHz for DAQ1000). Have live time characteristics such that the Pixel detector is live whenever the TPC is live. (PXL adds ≤ 5% additional dead time) Reduce the total data rate of the detector to a manageable level (< TPC rate of ~1MB / event). Reliable, cost effective, etc. Furthermore, this RDO system will be the basis of sensor testing including production probe testing so additional functionality will be included to enable this system to have the needed additional capabilities.

14. L. Greiner14PXL Sensor and RDO review – 06/23/2010 STAR Sensor generation and RDO attributes Pixel Sensors CDS ADC Data sparsification readout to DAQ analog signals Complementary detector readout MimoSTAR sensors 4 ms integration time PXL final sensors (Ultimate) < 200 μs integration time analog digital digital signals Disc. CDS Phase-1 sensors 640 μs integration time Sensor and RDO Development Path Develop sensor chips, 3 generation program (WBS 1.2.2.2) 1 2 3

15. L. Greiner15PXL Sensor and RDO review – 06/23/2010 STAR Summary The detector parameters presented have been established through simulation studies that have chosen an optimized operating point for the PXL detector through multi-parameter analysis of the entire upgrade system. This is a set of detector parameters that, when used together, provide the required tracking resolution and efficiency in the required momentum ranges to do the physics to the required sensitivity and in the required time. We will use these parameters as the basis for the detector design. Deviations will be subject to simulation to determine the effect on performance.

16. L. Greiner16PXL Sensor and RDO review – 06/23/2010 STAR backup

17. L. Greiner17PXL Sensor and RDO review – 06/23/2010 STAR Alternate Technologies Considered Hybrid –X 0 large (1.2%) –Pixel Size large (50  m x 450  m) –Specialized manufacturing - not readily available CCDs –Limited radiation tolerance –Slow frame rate, pileup issues –Specialized manufacturing DEPFET –Specialized manufacturing –very aggressive unproven technology MAPS sensors are the technology selected