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O'Neil, Judah

Publications and source records attributed to O'Neil, Judah.

Characterization of skipper CCDs for cosmological applications

We characterize the response of a novel 250 µm thick, fully-depleted Skipper Charged-Coupled Device (CCD) to visible/near-infrared light with a focus on potential applications for astronomical observations. We achieve stable, single-electron resolution with readout noise &sigma; 0.18 e - rms/pix from 400 non-destructive measurements of the charge in each pixel. We verify that the gain derived from photon transfer curve measurements agrees with the gain calculated from the quantized charge of individual electrons to within < 1%. We also perform relative quantum efficiency measurements and demonstrate high relative quantum efficiency at optical/near- infrared wavelengths, as is expected for a thick, fully depleted detector. Finally, we demonstrate the ability to perform multiple non-destructive measurements and achieve sub-electron readout noise over configurable sub- regions of the detector. This work is the first step toward demonstrating the utility of Skipper CCDs for future astronomical and cosmological applications.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Astro Skipper-CCD Detector

Cosmologists have determined that the majority of the universe is composed of dark energy and nonbaryonic (not made of atoms) dark matter. Dark energy is an unknown form of energy, hypothesized to be the cause of the accelerating expansion of the universe. Dark matter can not be detected electromagnetically, however cosmologists are confident it exists because of its gravitational effect on galaxies. In spiral galaxies, we observe stars that orbit at speeds that can not be accounted for by the gravitational force of visible matter. This puzzling result is contrary to standard Newtonian gravity, yet makes sense if one assumes the gravitational effects of an unseen mass[1]. Better, more sensitive detectors are required to perform detailed measurements of faint stars and galaxies that will allow us to further understand these phenomena.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗