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From the SiD homepage, "The Silicon Detector Design Study is being organized to develop the SiD Detector Concept into a detailed, optimized, and fully integrated detector design on a roughly one year time scale. The SiD concept incorporates Si/W calorimetry and Si tracking in a Linear Collider detector design which attempts to optimize physics performance while realistically constraining costs."
What is the GLD?
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LDC Detector Outline DocumentLDC Detector
What is the fourth concept?
Fourth Concept Outline Document
R&D
Where can I go for more information about ILC detector R&D programs?
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