Abstract
Arrays of 3D position-sensitive detectors (3DPSD), operating at room temperature and using cadmium zinc telluride (CZT) and thallium bromide (TIBr) sensors, are suitable for gamma-ray ...spectrometry in many applications. One detector configuration, the 3D position-sensitive Virtual Frisch-Grid detector (VFG), is particularly advantageous for integrating into large area arrays. The signals generated inside each detector of the array are captured with the anode, cathode and four pads that enable the reconstruction of the position and energy of the ionizing interaction by measurements of amplitude and timing of the signals. For these applications, a low-noise front-end ASIC has been developed, capable of processing bipolar signals (needed because of AC-coupling of certain electrodes). The ASIC can be coupled to an ADC in order to form a compound “waveform digitizer” capable of post-processing the analog signals and determining amplitude and timing information. This paper describes a 32-channel front-end ASIC that is suitable for reading out a 3 × 3 or 4 × 4 element matrix in the VFG configuration. Each channel is composed of a low-noise charge amplifier with an adaptive continuous reset feedback circuit suitable for both positive and negative charge, a first order shaper and a single-to-differential converter output stage. Voltage and current references are all internally generated by 10-bit DACs and the chip is fully controllable with the I
2
C communication protocol. The readout channel response has been verified using the implemented injection circuit. Linear behavior up to ∼75 ke
±
with the gain of ∼80 mV/fC, and up to ∼200 ke
±
with the gain of ∼30 mV/fC was demonstrated. In conclusion, the first test result waveforms using a
137
Cs radioactive source on a 5 × 5 × 12 mm
3
TIBr crystal are reported.
The ProtoDUNE-SP detector is a large-scale prototype of the Single-Phase (SP) Liquid Argon Time Projection Chamber (LArTPC) design proposed for the Deep Underground Neutrino Experiment (DUNE). 15,360 ...LArTPC wires are instrumented with low electronic noise pre-amplifier and digitization ASICs integrated into Front End Motherboards (FEMBs) operating at cryogenic temperature within the cryostat. The large number of electronics channels and high performance specifications required a large-scale production electronics quality control effort, careful installation into Anode Plane Assemblies (APAs), and rigorous detector commissioning. This successful collaboration-wide effort achieved a working LArTPC electronics channel percentage of 99.7% (15,318 of 15,360 channels in total), whose operating performance exceeded expectations. We summarize the ProtoDUNE-SP cold electronics design and quality control, installation, and commissioning efforts that enabled this excellent electronics performance.
Position sensitivity enables the correction of response non-uniformities in room-temperature semiconductor detectors caused by crystal defects and other factors. It can also be used to pinpoint the ...exact location of crystal defects responsible for the response variations. This work describes a technique for revealing and visualizing the detector regions affecting the charge collection efficiency in CdZnTe (CZT), TlBr, and CsPbBr3 detectors configured as position-sensitive virtual Frisch-grid (VFG) devices. The technique correlates the photopeak events in energy spectra with their spatial distributions inside the detectors using the position information. By selecting the events from narrow energy intervals within a photopeak, we can visualize the detector volumes with particular charge collection efficiencies, which, in turn, correlate with the locations of electrode and crystal defects. We demonstrate this technique in several examples. Columnar structures in the volume plots (position distribution maps) are consistent with signal losses near or at the anode in selected samples of CZT and TlBr. Structures exhibiting a distinct depth dependence are consistent with grain boundaries or other crystal defects.
A line driver with configurable pre-emphasis is implemented in a 65 nm CMOS process. The driver utilizes a three-tap feed-forward equalization (FFE) architecture. The relative delays between the taps ...are selectable in increments of 1/16th of the unit interval (UI) via an 8-stage delay-locked loop (DLL) and digital interpolator. It is also possible to control the output amplitude and source impedance for each tap via a programmable array of eight source-series terminated (SST) drivers. The entire design consumes 9 mW from a 1.2 V supply at 1 Gb/s.
The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber with an active volume of 7.2×6.1×7.0 m3. It is installed at the CERN Neutrino Platform in a specially-constructed beam ...that delivers charged pions, kaons, protons, muons and electrons with momenta in the range 0.3 GeV/c to 7 GeV/c. Beam line instrumentation provides accurate momentum measurements and particle identification. The ProtoDUNE-SP detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment, and it incorporates full-size components as designed for that module. This paper describes the beam line, the time projection chamber, the photon detectors, the cosmic-ray tagger, the signal processing and particle reconstruction. It presents the first results on ProtoDUNE-SP's performance, including noise and gain measurements, dE/dx calibration for muons, protons, pions and electrons, drift electron lifetime measurements, and photon detector noise, signal sensitivity and time resolution measurements. The measured values meet or exceed the specifications for the DUNE far detector, in several cases by large margins. ProtoDUNE-SP's successful operation starting in 2018 and its production of large samples of high-quality data demonstrate the effectiveness of the single-phase far detector design.
The Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and ...particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. The experiment consists of a near detector, sited close to the source of the beam, and a far detector, sited along the beam at a large distance. This document, the DUNE Near Detector Conceptual Design Report (CDR), describes the design of the DUNE near detector and the science program that drives the design and technology choices. The goals and requirements underlying the design, along with projected performance are given. It serves as a starting point for a more detailed design that will be described in future documents.
Abstract
A line driver with configurable pre-emphasis is implemented in a 65 nm
CMOS process. The driver utilizes a three-tap feed-forward equalization
architecture. The relative delays between the ...taps are selectable in increments
of 1/16th of the unit interval via an 8-stage delay-locked loop and digital
interpolator. It is also possible to control the output amplitude and source
impedance for each tap via a programmable array of eight source-series
terminated drivers. The entire design consumes 9 mW from a 1.2 V supply
at 1 Gb/s.
A line driver with configurable pre-emphasis is implemented in a 65 nmCMOS process. The driver utilizes a three-tap feed-forward equalizationarchitecture. The relative delays between the taps are ...selectable in incrementsof 1/16th of the unit interval via an 8-stage delay-locked loop and digitalinterpolator. It is also possible to control the output amplitude and sourceimpedance for each tap via a programmable array of eight source-seriesterminated drivers. The entire design consumes 9 mW from a 1.2 V supplyat 1 Gb/s.
Abstract
The ProtoDUNE-SP detector is a single-phase liquid argon
time projection chamber (LArTPC) that was constructed and operated
in the CERN North Area at the end of the H4 beamline. This ...detector
is a prototype for the first far detector module of the Deep
Underground Neutrino Experiment (DUNE), which will be constructed at
the Sandford Underground Research Facility (SURF) in Lead, South
Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size
components as designed for DUNE and has an active volume of
7 × 6 × 7.2 m
3
. The H4 beam delivers incident
particles with well-measured momenta and high-purity particle
identification. ProtoDUNE-SP's successful operation between 2018 and
2020 demonstrates the effectiveness of the single-phase far detector
design. This paper describes the design, construction, assembly and
operation of the detector components.
Liquid xenon time projection chambers are promising detectors to search for neutrinoless double beta decay (0
ν
β
β
), due to their response uniformity, monolithic sensitive volume, scalability to ...large target masses, and suitability for extremely low background operations. The nEXO collaboration has designed a tonne-scale time projection chamber that aims to search for 0
ν
β
β
of
136
Xe with projected half-life sensitivity of
1.35
×
10
28
yr. To reach this sensitivity, the design goal for nEXO is
≤
1% energy resolution at the decay
Q
-value (
2458.07
±
0.31
keV). Reaching this resolution requires the efficient collection of both the ionization and scintillation produced in the detector. The nEXO design employs Silicon Photo-Multipliers (SiPMs) to detect the vacuum ultra-violet, 175 nm scintillation light of liquid xenon. This paper reports on the characterization of the newest vacuum ultra-violet sensitive Fondazione Bruno Kessler VUVHD3 SiPMs specifically designed for nEXO, as well as new measurements on new test samples of previously characterised Hamamatsu VUV4 Multi Pixel Photon Counters (MPPCs). Various SiPM and MPPC parameters, such as dark noise, gain, direct crosstalk, correlated avalanches and photon detection efficiency were measured as a function of the applied over voltage and wavelength at liquid xenon temperature (163 K). The results from this study are used to provide updated estimates of the achievable energy resolution at the decay
Q
-value for the nEXO design.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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