Speaker
Description
GAMPix (Grid-Activated Multi-scale Pixel readout) is a low-power charge-readout system for time projection chambers (TPCs) that pairs coarse induction wire grids with fine pixel planes. The wire signal triggers the pixels of a rapidly power-cycled ASIC, which then integrate the deposited charge, enabling sub-millimeter track imaging with full energy reconstruction while cutting readout power and data volume by three to four orders of magnitude ($10^3$–$10^4$). Developed for GammaTPC, a proposed MeV gamma-ray telescope based on liquid-argon TPC (LArTPC) technology, GAMPix is broadly applicable to other large-volume noble-element detectors. We report the first proof-of-concept ASIC, GAMPixPi_v1: a $5\times5\ \mathrm{mm^2}$ chip in $130\ \mathrm{nm}$ CMOS with an $8\times8$ pixel matrix providing per-pixel amplification, correlated double sampling, and in-pixel digitization. First characterization immersed in liquid argon ($87\ \mathrm{K}$) demonstrates that the full signal chain operates as designed: microsecond-scale turn-on validates the power-pulsing scheme, and all key performance metrics meet specification.