0000000000023662
AUTHOR
Ana M. Gil
Design and characterization of the SiPM tracking system of NEXT-DEMO, a demonstrator prototype of the NEXT-100 experiment
NEXT-100 experiment aims at searching the neutrinoless double-beta decay of the Xe-136 isotope using a TPC filled with a 100 kg of high-pressure gaseous xenon, with 90% isotopic enrichment. The experiment will take place at the Laboratorio Subterraneo de Canfranc (LSC), Spain. NEXT-100 uses electroluminescence (EL) technology for energy measurement with a resolution better than 1% FWHM. The gaseous xenon in the TPC additionally allows the tracks of the two beta particles to be recorded, which are expected to have a length of up to 30 cm at 10 bar pressure. The ability to record the topological signature of the beta beta 0 nu events provides a powerful background rejection factor for the bet…
TCNQ radical salts containing magnetic complexes: Different interaction modes of TCNQ with Copper tetraazamacrocycles
Abstract This work is devoted to the study of compounds [M(N 4 )](TCNQ) n , where N 4 = saturated or unsaturated tetraazamacrocycles, TCNQ= 7,7,8,8-tetracyanoquinodimethane, n= 2, 3. The metal is coordinated to two TCNQ groups only when there is coordinative unsaturation on it. When n= 2 all the TCNQ units are radical anions and no charge delocalization is observed. In the compounds with n= 3 only 2 3 of the TCNQ are negatively charged and a greater charge delocalization is possible. This delocalization only appears when none of the TCNQ's are coordinated to the metal and it is reflected in the higher conductivity values obtained in the solid state.
Operation and first results of the NEXT-DEMO prototype using a silicon photomultiplier tracking array
NEXT-DEMO is a high-pressure xenon gas TPC which acts as a technological test-bed and demonstrator for the NEXT-100 neutrinoless double beta decay experiment. In its current configuration the apparatus fully implements the NEXT-100 design concept. This is an asymmetric TPC, with an energy plane made of photomultipliers and a tracking plane made of silicon photomultipliers (SiPM) coated with TPB. The detector in this new configuration has been used to reconstruct the characteristic signature of electrons in dense gas, demonstrating the ability to identify the MIP and "blob" regions. Moreover, the SiPM tracking plane allows for the definition of a large fiducial region in which an excellent e…
Description and commissioning of NEXT-MM prototype: first results from operation in a Xenon-Trimethylamine gas mixture
[EN] A technical description of NEXT-MM and its commissioning and first performance is reported. Having an active volume of ∼35 cm drift × 28 cm diameter, it constitutes the largest Micromegas-read TPC operated in Xenon ever constructed, made by a sectorial arrangement of the 4 largest single wafers manufactured with the Microbulk technique to date. It is equipped with a suitably pixelized readout and with a sufficiently large sensitive volume (∼23 l) so as to contain long (∼20 cm) electron tracks. First results obtained at 1 bar for Xenon and Trymethylamine (Xe-(2%)TMA) mixture are presented. The TPC can accurately reconstruct extended background tracks. An encouraging fu…
SiPMs coated with TPB: coating protocol and characterization for NEXT
[EN] Silicon photomultipliers (SiPM) are the photon detectors chosen for the tracking readout in NEXT, a neutrinoless \bb decay experiment which uses a high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology in this gaseous detector is a key handle for background rejection. Among the commercially available sensors that can be used for tracking, SiPMs offer important advantages, mainly high gain, ruggedness, cost-effectiveness and radio-purity. Their main drawback, however, is their non sensitivity in the emission spectrum of the xenon scintillation (peak at 175 nm). This is overcome by coating these sensors with the organic wavelength shifte…