No Arabic abstract
The Short Baseline Near Detector (SBND) is one of three liquid argon (LAr) neutrino detectors sitting in the Booster Neutrino Beam (BNB) at Fermilab as part of the Short Baseline Neutrino (SBN) program. The detector is in a cryostat holding 260-ton of LAr and consists of four 2.5 m (L) $times$ 4 m (W) Anode Plane Assembles (APAs) and two Cathode Plane Assemblies (CPAs), which leads to 11,264 Time Projection Chamber (TPC) readout channels and two separate 2 m long drift regions. As an enabling technology, Cold Electronics (CE) developed for cryogenic temperature operation makes possible an optimum balance among various design and performance requirements for such large sized detectors. Brookhaven National Laboratory (BNL) has been leading the R&D and implementation of the entire front-end CE system for LAr TPC readout in collaboration with other SBND institutes. The front-end readout electronics system includes the cold front-end electronics placed close to the wire electrodes, which detects and digitizes the charge signal in LAr, as well as the warm interface electronics placed on the signal feed-through flange outside of the cryostat, which further organizes and transmits the digitized signal to the DAQ system. An extensive study of electronics suitable for 77 K - 300 K, including the custom designed front-end ASIC and commercial components, e.g. ADC and FPGA, has been made to meet requirements such as low noise, low power consumption, high reliability and long lifetime. Furthermore, an integral design concept of APA, CE, feed-through, warm interface electronics with local diagnostics, grounding and isolation rules has been practiced with vertical slice test stands to make projection of the CE performance in the SBND detector.
Short Baseline Near Detector (SBND), which is a 260-ton LAr TPC as near detector in Short Baseline Neutrino (SBN) program, consists of 11,264 TPC readout channels. As an enabling technology for noble liquid detectors in neutrino experiments, cold electronics developed for extremely low temperature (77K - 89K) decouples the electrode and cryostat design from the readout design. With front-end electronics integrated with detector electrodes, the noise is independent of the fiducial volume and about half as with electronics at room temperature. Digitization and signal multiplexing to high speed serial links inside cryostat result in large reduction in the quantity of cables (less outgassing) and the number of feed-throughs, therefore minimize the penetration and simplify the cryostat design. Being considered as an option for the TPC readout, several Commercial-Off-The-Shelf (COTS) ADC chips have been identified as good candidates for operation in cryogenic temperature after initial screening test. Because Hot Carrier Effects (HCE) degrades CMOS device lifetime, one candidate, ADI AD7274 fabricated in TSMC 350nm CMOS technology, of which lifetime at cryogenic temperature is studied. The lifetime study includes two phases, the exploratory phase and the validation phase. This paper describes the test method, test setup, observations in the exploratory phase and the validation phase. Based on the current test data, the preliminary lifetime projection of AD7274 is about 6.1 $times$ $10^6$ years at 2.5V operation at cryogenic temperature, which means the HCE degradation is negligible during the SBND service life.
ARGONTUBE is a liquid argon time projection chamber (TPC) with an electron drift length of up to 5 m equipped with cryogenic charge-sensitive preamplifiers. In this work, we present results on its performance including a comparison of the new cryogenic charge-sensitive preamplifiers with the previously used room-temperature-operated charge preamplifiers.
In this paper we give a concise description of a liquid argon time projection chamber (LAr TPC) developed at Yale, and present results from its first calibration run with cosmic rays.
The dual phase Liquid Argon Time Projection Chamber (LAr TPC) is the state-of-art technology for neutrino detection thanks to its superb 3D tracking and calorimetry performance. Its main feature is the charge amplification in gas argon which provides excellent signal-to-noise ratio. Electrons produced in the liquid argon are extracted in the gas phase. Here, a readout plane based on Large Electron Multiplier detectors provides amplification of the charges before its collection onto an anode with strip readout. The charge amplification enables constructing fully homoge- nous giant LAr-TPCs with tuneable gain, excellent charge imaging performance and increased sensitivity to low energy events. Following a staged approach the WA105 collaboration is con- structing a dual phase LAr-TPC with an active volume of 3x1x1m3 that will soon be tested with cosmic rays. Its construction and operation aims to test scalable solutions for the crucial aspects of this technology: ultra high argon purity in non-evacuable tank, large area dual phase charge readout system in several square meter scale, and accessible cold front-end electronics. A mile- stone was achieved last year in the completion of the 24 m3 cryostat that hosts the TPC. This is the first cryostat based on membrane technology to be constructed at CERN and is therefore also an important step towards the realisation of the upcoming protoDUNE detectors. The 3x1x1m3 dual phase LAr-TPC will be described in and we will report on the latest construction progress.
For the future neutrino oscillation experiment DUNE, liquid argon time projections chambers with a fiducial mass of 10 kton each are foreseen. The dual phase concept is one of the two implementations considered, wherein electrons produced by ionization in the liquid are extracted to a gaseous region above the liquid where they are amplified. For the amplification, large electron multipliers will be used. The technology was tested in various prototypes, most recently with a 3 x 1 x 1 m$^3$ large setup. An even larger prototype of 6 x 6 x 6 m$^3$ is currently being constructed and will start operation in 2019. An intensive R&D program was carried out with the focus on achieving an effective gain of at least 20. In the simulation study here presented for the first time not only the electron signal is considered but also the ion backflow and the expected production of secondary scintillation light is studied, because the latter might limit the capability of the detector to trigger on low energetic no-beam physics. It is found that the ion backflow and the light yield can be expected to be very large. The results for the effective gain show a discrepancy with experimental data, both in size and shape of the gain curve. Based on literature studies, it is argued that photon feedback contributes to the gain in detectors filled with pure noble gases, especially in the case of pure argon.