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Noise Characterization of the SIDECAR ASIC Readout Chip for SNAP. Martin Diaz Stanford Linear Accelerator Center August 14, 2008. Our Expanding Universe. The expansion history of the universe can be mapped out What is causing it to accelerate?. Dark Energy.
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Noise Characterization of the SIDECAR ASIC Readout Chip for SNAP Martin Diaz Stanford Linear Accelerator Center August 14, 2008
Our Expanding Universe The expansion history of the universe can be mapped out What is causing it to accelerate?
Dark Energy Believed to be the reason for the accelerating expansion Dark energy dominates our universe Yet, little is known about it
SuperNova Acceleration Probe Part of the Joint Dark Energy Mission (JDEM) Between NASA and DOE
SuperNova Acceleration Probe Weak gravitational lensing N. Kaiser
SuperNova Acceleration Probe Measure changes in the expansion rate with the help of type Ia supernova
Type Ia Supernova No observed Hydrogen Found in spiral and elliptical galaxies Outer stellar layers missing prior to explosion
Type Ia Supernova Binary System Matter is transferred Causes white dwarf to implode
Type Ia Supernova Luminosity is from radioactive decay of Cobalt and Nickel into Iron Same Fuel = Same Luminosity Act as “Standard Candles”
SuperNova Acceleration Probe SNAP will measure: Peak brightness Distance away Redshift Expansion factor
SuperNova Acceleration Probe SIDECAR ASIC
SIDECAR System for Image Digitization Enhancement, Control and Retrieval Application Specific Integrated Circuit (ASIC) Alternative to discrete electronics
SIDECAR Converts Analog signal from image detector to digital signal Easily transmitted and stored
SIDECAR Problem: Reduce noise Method: Optimization of microcode Compare multiple images Without image sensor
SIDECAR Procedure Two consecutive images Take difference in pixel value Collect to form histogram and obtain RMS Results
SIDECAR Procedure After some modification to the Amplifier Reset Results
SIDECAR Procedure 100 images Compare a single pixel Results
SIDECAR Procedure 50 images 256 pixels Results
Conclusion After testing the SIDECAR in 32 channel mode Microcode optimization RMS value as low as 4.8
Future Work Operation under cryogenic temperatures Integration with Hybrid Visible Silicon Imager (HyViSI) imaging sensor.
Acknowledgements Thank you to my mentor Leonid Sapozhnikov and the rest of the SNAP team. I would also like to thank the Department of Energy and the SULI staff.
Resources http://snap.lbl.gov C. Bebek, “The SNAP Space Mission”, Nuclear Instruments and Methods in Physics Research, Vol. 579, Issue 2, pp. 848-852, 2007. M. Loose et al., “The SIDECAR ASIC – Focal Plane Electronics on a Single CHIP”, Cryogenic Optical Systems and Instruments XI, Proc. SPIE Vol. 5904, pp. 293-302, 2005.