We present results of a dark matter search performed with a 0.6 kg d exposure of the DAMIC experiment at the SNOLAB underground laboratory. We measure the energy spectrum of ionization events in the bulk silicon of charge-coupled devices down to a signal of 60 eV electron equivalent. The data are consistent with radiogenic backgrounds, and constraints on the spin-independent WIMP-nucleon elastic-scattering cross section are accordingly placed. A region of parameter space relevant to the potential signal from the CDMS-II Si experiment is excluded using the same target for the first time. This result obtained with a limited exposure demonstrates the potential to explore the low-mass WIMP region ($<10\mathrm{GeV}{c}^{-2}$) with the upcoming DAMIC100, a 100 g detector currently being installed in SNOLAB.

We present direct detection constraints on the absorption of hidden-photon dark matter with particle masses in the range $1.2–30\mathrm{eV}{c}^{-2}$ with the DAMIC experiment at SNOLAB. Under the assumption that the local dark matter is entirely constituted of hidden photons, the sensitivity to the kinetic mixing parameter $\kappa$ is competitive with constraints from solar emission, reaching a minimum value of $2.2\times {10}^{-14}$ at $17\mathrm{eV}{c}^{-2}$. These results are the most stringent direct detection constraints on hidden-photon dark matter in the galactic halo with masses $3–12\mathrm{eV}{c}^{-2}$ and the first demonstration of direct experimental sensitivity to ionization signals $<12\mathrm{eV}$ from dark matter interactions.

The CONNIE experiment uses fully depleted, high resistivity CCDs as particle detectors in an attempt to measure for the first time the Coherent Neutrino-Nucleus Elastic Scattering of antineutrinos from a nuclear reactor with silicon nuclei. This talk, given at the XV Mexican Workshop on Particles and Fields (MWPF), discussed the potential of CONNIE to perform this measurement, the installation progress at the Angra dos Reis nuclear power plant, as well as the plans for future upgrades.

<!-- *** Custom HTML *** --> The development of the Skipper-charge-coupled devices (Skipper-CCDs) has been a major technological breakthrough for sensing very weak ionizing particles. The sensor allows to reach the ultimate sensitivity of silicon material as a charge signal sensor by unambiguous determination of the charge signal collected by each cell or pixel, even for single electron–hole pair ionization. Extensive use of the technology was limited by the lack of specific equipment to operate the sensor at the ultimate performance. A simple, single-board Skipper-CCD controller designed by the authors is presented and aimed for the operation of the detector in high sensitivity scientific applications. Our article describes the main components and functionality of the so-called low threshold acquisition controller together with experimental results when connected to a Skipper-CCD sensor. Measurements show unprecedented deep subelectron noise of 0.039erms−/pix by nondestructively measuring the charge 5000 times in each pixel.

A novel readout architecture that uses multiple nondestructive floating-gate amplifiers (FGAs) to achieve subelectron readout noise in a thick, fully depleted silicon detector is presented. This multiple-amplifier sensing charge-coupled device (MAS-CCD) can perform multiple independent charge measurements with each amplifier; measurements with multiple amplifiers can then be combined to further reduce the readout noise. This allows getting subelectron noise operation in less time compared with single-nondestructive-amplifier CCDs. The performance of this detector is demonstrated, emphasizing the ability to resolve individual quanta and to combine measurements across amplifiers to reduce readout noise. These characteristics make it a candidate technology for astronomical observations, quantum imaging, and low-energy interacting particles.