211 research outputs found
First results from a multiplexed and massive instrument with sub-electron noise Skipper-CCDs
We present a new instrument composed of a large number of sub-electron noise
Skipper-CCDs operated with a two stage analog multiplexed readout scheme
suitable for scaling to thousands of channels. New, thick, Mpix sensors,
from a new foundry, are glued into a Multi-Chip Module (MCM) printed circuit
board on a ceramic substrate which has 16 sensors each. The instrument, that
can hold up-to 16 MCMs, a total of 256 Skipper-CCD sensors (called a
Super-Module with grams of active mass and Mpix), is part
of the RD effort of the OSCURA experiment which will have
super-modules. Experimental results with MCMs and Skipper-CCDs
sensors are presented in this paper. This is already the largest ever build
instrument with single electron sensitivity CCDs using nondestructive readout,
both, in terms of active mass and number of channels.Comment: Corrected minor typo
Results of the engineering run of the coherent neutrino nucleus interaction experiment (CONNIE)
The CONNIE detector prototype is operating at a distance of 30 m from the core of a 3.8 GWth nuclear reactor with the goal of establishing Charge-Coupled Devices (CCD) as a new technology for the detection of coherent elastic neutrino-nucleus scattering. We report on the results of the engineering run with an active mass of 4 g of silicon. The CCD array is described, and the performance observed during the first year is discussed. A compact passive shield was deployed around the detector, producing an order of magnitude reduction in the background rate. The remaining background observed during the run was stable, and dominated by internal contamination in the detector packaging materials. The in-situ calibration of the detector using X-ray lines from fluorescence demonstrates good stability of the readout system. The event rates with the reactor ON and OFF are compared, and no excess is observed coming from nuclear fission at the power plant. The upper limit for the neutrino event rate is set two orders of magnitude above the expectations for the standard model. The results demonstrate the cryogenic CCD-based detector can be remotely operated at the reactor site with stable noise below2 e RMS and stable background rates. The success of the engineering test provides a clear path for the upgraded 100 g detector to be deployed during 2016.Fil: Aguilar Arevalo, A.. Universidad Nacional Autónoma de México; MéxicoFil: Bertou, Xavier Pierre Louis. Comisión Nacional de EnergÃa Atómica; Argentina. Comisión Nacional de EnergÃa Atómica. Fundación José A. Balseiro; ArgentinaFil: Bonifazi, C.. Universidade Federal do Rio de Janeiro; BrasilFil: Butner, M.. Fermi National Accelerator Laboratory; Estados UnidosFil: Cancelo, G.. Fermi National Accelerator Laboratory; Estados UnidosFil: Castañeda Vazquez, A.. Universidad Nacional Autónoma de México; MéxicoFil: Cervantes Vergara, B.. Universidad Nacional Autónoma de México; MéxicoFil: Chavez, C. R.. Universidad Nacional de Asunción; ParaguayFil: Da Motta, H.. Centro Brasileiro de Pesquisas FÃsicas; BrasilFil: D'Olivo, J. C.. Universidad Nacional Autónoma de México; MéxicoFil: Dos Anjos, J.. Centro Brasileiro de Pesquisas FÃsicas; BrasilFil: Estrada, J.. Fermi National Accelerator Laboratory; Estados UnidosFil: Fernández Moroni, Guillermo. Universidad Nacional del Sur. Departamento de IngenierÃa Eléctrica y de Computadoras. Instituto ; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Ford, R.. Fermi National Accelerator Laboratory; Estados UnidosFil: Foguel, A.. Centro Brasileiro de Pesquisas FÃsicas; Brasil. Universidade Federal do Rio de Janeiro; BrasilFil: Hernandez Torres, K. P.. Universidad Nacional Autónoma de México; MéxicoFil: Izraelevitch, F.. Fermi National Accelerator Laboratory; Estados UnidosFil: Kavner, A.. University of Michigan; Estados UnidosFil: Kilminster, B.. Universitat Zurich; SuizaFil: Kuk, K.. Fermi National Accelerator Laboratory; Estados UnidosFil: Lima Jr, H. P.. Centro Brasileiro de Pesquisas FÃsicas; BrasilFil: Makler, M.. Centro Brasileiro de Pesquisas FÃsicas; BrasilFil: Molina, J.. Universidad Nacional de Asunción; ParaguayFil: Moreno Granados, G.. Universidad Nacional Autónoma de México; MéxicoFil: Moro, Juan Manuel. Universidad Nacional del Sur. Departamento de IngenierÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Paolini, Eduardo Emilio. Universidad Nacional del Sur. Departamento de IngenierÃa Eléctrica y de Computadoras. Instituto ; ArgentinaFil: Sofo Haro, Miguel Francisco. Comision Nacional de Energia Atomica. Gerencia D/area de Energia Nuclear; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Tiffenberg, Javier Sebastian. Fermi National Accelerator Laboratory; Estados Unidos. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Trillaud, F.. Universidad Nacional Autónoma de México; MéxicoFil: Wagner, S.. Centro Brasileiro de Pesquisas FÃsicas; Brasil. Pontificia Universidade Católica do Rio Grande do Sul; Brasi
Constraints on the electron-hole pair creation energy and Fano factor below 150 eV from Compton scattering in a Skipper-CCD
Fully-depleted thick silicon Skipper-charge-coupled devices (Skipper-CCDs)
are an important technology to probe neutrino and light-dark-matter
interactions due to their sub-electron read-out noise. However, the successful
search for rare neutrino or dark-matter events requires the signal and all
backgrounds to be fully characterized. In particular, a measurement of the
electron-hole pair creation energy below 150 eV and the Fano factor are
necessary for characterizing the dark matter and neutrino signals. Moreover,
photons from background radiation may Compton scatter in the silicon bulk,
producing events that can mimic a dark matter or neutrino signal. We present a
measurement of the Compton spectrum using a Skipper-CCD and a Am
source. With these data, we estimate the electron-hole pair-creation energy to
be eV at 130 K in the energy range between 99.3 eV
and 150 eV. By measuring the widths of the steps at 99.3 eV and 150 eV in the
Compton spectrum, we introduce a novel technique to measure the Fano factor,
setting an upper limit of 0.31 at 90% C.L. These results prove the potential of
Skipper-CCDs to characterize the Compton spectrum and to measure precisely the
Fano factor and electron-hole pair creation energy below 150 eV
Design of a Skipper CCD Focal Plane for the SOAR Integral Field Spectrograph
We present the development of a Skipper Charge-Coupled Device (CCD) focal
plane prototype for the SOAR Telescope Integral Field Spectrograph (SIFS). This
mosaic focal plane consists of four 6k 1k, 15 m pixel Skipper
CCDs mounted inside a vacuum dewar. We describe the process of packaging the
CCDs so that they can be easily tested, transported, and installed in a mosaic
focal plane. We characterize the performance of m thick,
fully-depleted engineering-grade Skipper CCDs in preparation for performing
similar characterization tests on science-grade Skipper CCDs which will be
thinned to 250m and backside processed with an antireflective coating. We
achieve a single-sample readout noise of for the best
performing amplifiers and sub-electron resolution (photon counting
capabilities) with readout noise from 800
measurements of the charge in each pixel. We describe the design and
construction of the Skipper CCD focal plane and provide details about the
synchronized readout electronics system that will be implemented to
simultaneously read 16 amplifiers from the four Skipper CCDs (4-amplifiers per
detector). Finally, we outline future plans for laboratory testing,
installation, commissioning, and science verification of our Skipper CCD focal
plane
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