For large volume neutrino and antineutrino detectors it is crucial to have an efficient data acquisition system capable of digitizing data from thousands of detection channels. Here we present a ...flexible DAQ system architecture consisting of a large number of fast waveform digitizers and configurable FPGA-based trigger logic. The current implementation of the system is functioning in the Borexino neutrino detector providing zero dead time spectroscopy data in the energy range from 1 up to 100 MeV. Acquisition complex in combination with our custom analysis software is successfully being used for registration of geoneutrinos, as well as search for neutrino signal from GRBs, solar netrino spectroscopy and other applications.
Industrial Detector of REactor Antineutrinos for Monitoring (iDREAM) is a 1 ton Gd-doped liquid scintillator detector mounted in the Kalinin nuclear power plant (Russia), 20 m from the 3 GW
VVER type ...commercial reactor. Antineutrinos are detected via inverse beta decay on protons. Beginning in 2021, the detector is collecting data both in reactor ON and OFF modes. The first iDREAM antineutrino results are presented, showing no doubt on the proper operation of the detector as a counting device.
Reactor antineutrino detector iDREAM Gromov, M B; Lukyanchenko, G A; Novikova, G J ...
Journal of physics. Conference series,
09/2017, Letnik:
888, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Industrial Detector for Reactor Antineutrino Monitoring (iDREAM) is a compact (≈ 3.5m2) industrial electron antineutrino spectrometer. It is dedicated for remote monitoring of PWR reactor operational ...modes by neutrino method in real-time. Measurements of antineutrino flux from PWR allow to estimate a fuel mixture in active zone and to check the status of the reactor campaign for non-proliferation purposes. LAB-based gadolinium doped scintillator is exploited as a target. Multizone architecture of the detector with gamma-catcher surrounding fiducial volume and plastic muon veto above and below ensure high efficiency of IBD detection and background suppression. DAQ is based on Flash ADC with PSD discrimination algorithms while digital trigger is programmable and flexible due to FPGA. The prototype detector was started up in 2014. Preliminary works on registration Cerenkov radiation produced by cosmic muons were established with distilled water inside the detector in order to test electronic and slow control systems. Also in parallel a long-term measurements with different scintillator samples were conducted.
In the core of the Sun, energy is released through sequences of nuclear reactions that convert hydrogen into helium. The primary reaction is thought to be the fusion of two protons with the emission ...of a low-energy neutrino. These so-called pp neutrinos constitute nearly the entirety of the solar neutrino flux, vastly outnumbering those emitted in the reactions that follow. Although solar neutrinos from secondary processes have been observed, proving the nuclear origin of the Sun's energy and contributing to the discovery of neutrino oscillations, those from proton-proton fusion have hitherto eluded direct detection. Here we report spectral observations of pp neutrinos, demonstrating that about 99 per cent of the power of the Sun, 3.84 × 10(33) ergs per second, is generated by the proton-proton fusion process.
Neutrinos emitted in the carbon, nitrogen, oxygen (CNO) fusion cycle in the Sun are a sub-dominant, yet crucial component of solar neutrinos whose flux has not been measured yet. The Borexino ...experiment at the Laboratori Nazionali del Gran Sasso (Italy) has a unique opportunity to detect them directly thanks to the detector’s radiopurity and the precise understanding of the detector backgrounds. We discuss the sensitivity of Borexino to CNO neutrinos, which is based on the strategies we adopted to constrain the rates of the two most relevant background sources,
pep
neutrinos from the solar
pp
-chain and
210
Bi beta decays originating in the intrinsic contamination of the liquid scintillator with
210
Pb. Assuming the CNO flux predicted by the high-metallicity Standard Solar Model and an exposure of 1000 days
×
71.3 t, Borexino has a median sensitivity to CNO neutrino higher than 3
σ
. With the same hypothesis the expected experimental uncertainty on the CNO neutrino flux is 23%, provided the uncertainty on the independent estimate of the
210
Bi
interaction rate is 1.5
cpd
/
100
ton
. Finally, we evaluated the expected uncertainty of the C and N abundances and the expected discrimination significance between the high and low metallicity Standard Solar Models (HZ and LZ) with future more precise measurement of the CNO solar neutrino flux.
Abstract
Cosmogenic radio-nuclei are an important source of background for low-energy neutrino experiments. In Borexino, cosmogenic
$$^{11}$$
11
C decays outnumber solar
pep
and CNO neutrino events ...by about ten to one. In order to extract the flux of these two neutrino species, a highly efficient identification of this background is mandatory. We present here the details of the most consolidated strategy, used throughout Borexino solar neutrino measurements. It hinges upon finding the space-time correlations between
$$^{11}$$
11
C decays, the preceding parent muons and the accompanying neutrons. This article describes the working principles and evaluates the performance of this Three-Fold Coincidence (TFC) technique in its two current implementations: a hard-cut and a likelihood-based approach. Both show stable performances throughout Borexino Phases II (2012–2016) and III (2016–2020) data sets, with a
$$^{11}$$
11
C tagging efficiency of
$$\sim 90$$
∼
90
% and
$$\sim $$
∼
63–66 % of the exposure surviving the tagging. We present also a novel technique that targets specifically
$$^{11}$$
11
C produced in high-multiplicity during major spallation events. Such
$$^{11}$$
11
C appear as a
burst
of events, whose space-time correlation can be exploited. Burst identification can be combined with the TFC to obtain about the same tagging efficiency of
$$\sim 90\%$$
∼
90
%
but with a higher fraction of the exposure surviving, in the range of
$$\sim $$
∼
66–68 %.
We present the results of a low-energy neutrino search using the Borexino detector in coincidence with the gravitational wave (GW) events GW 150914, GW 151226, and GW 170104. We searched for ...correlated neutrino events with visible energies greater than 250 keV within a time window of 500 s centered around the GW detection time. A total of five candidates were found for all three GW events combined. This is consistent with the expected number of solar neutrino and background events. As a result, we have obtained the best current upper limits on all flavor neutrino ( e , , τ ) fluence associated with GW events, in the neutrino energy range 0.5-5.0 MeV.
We present a measurement of the geo-neutrino signal obtained from 1353 days of data with the Borexino detector at Laboratori Nazionali del Gran Sasso in Italy. With a fiducial exposure of ...(3.69±0.16)×1031 proton × year after all selection cuts and background subtraction, we detected (14.3±4.4) geo-neutrino events assuming a fixed chondritic mass Th/U ratio of 3.9. This corresponds to a geo-neutrino signal Sgeo=(38.8±12.0) TNU with just a 6×10−6 probability for a null geo-neutrino measurement. With U and Th left as free parameters in the fit, the relative signals are STh=(10.6±12.7) TNU and SU=(26.5±19.5) TNU. Borexino data alone are compatible with a mantle geo-neutrino signal of (15.4±12.3) TNU, while a combined analysis with the KamLAND data allows to extract a mantle signal of (14.1±8.1) TNU. Our measurement of 31.2−6.1+7.0 reactor anti-neutrino events is in agreement with expectations in the presence of neutrino oscillations.