Borexino could efficiently distinguish between α and β radiation in its liquid scintillator by the characteristic time profile of its scintillation pulse. This α / β discrimination, first ...demonstrated on the ton scale in the counting test facility prototype, was used throughout the lifetime of the experiment between 2007 and 2021. With this method, the α events are identified and subtracted from the solar neutrino events similar to β . This is particularly important in liquid scintillators, as the α scintillation is strongly quenched. In Borexino, the prominent Po 210 decay peak was a background in the energy range of electrons scattered from Be 7 solar neutrinos. Optimal α / β discrimination was achieved with a , with a higher ability to leverage the timing information of the scintillation photons detected by the photomultiplier tubes. An event-by-event, high efficiency, stable, and uniform pulse shape discrimination was essential in characterizing the spatial distribution of background in the detector. This benefited most Borexino measurements, including solar neutrinos in the p p chain and the first direct observation of the CNO cycle in the Sun. This paper presents key milestones in α / β discrimination in Borexino as a term of comparison for current and future large liquid scintillator detectors. Published by the American Physical Society 2024
The search for neutrino events in correlation with gravitational wave (GW) events for three observing runs (O1, O2 and O3) from 09/2015 to 03/2020 has been performed using the Borexino data-set of ...the same period. We have searched for signals of neutrino-electron scattering and inverse beta-decay (IBD) within a time window of Formula omitted s centered at the detection moment of a particular GW event. The search was done with three visible energy thresholds of 0.25, 0.8 and 3.0 MeV. Two types of incoming neutrino spectra were considered: the mono-energetic line and the supernova-like spectrum. GW candidates originated by merging binaries of black holes (BHBH), neutron stars (NSNS) and neutron star and black hole (NSBH) were analyzed separately. Additionally, the subset of most intensive BHBH mergers at closer distances and with larger radiative mass than the rest was considered. In total, follow-ups of 74 out of 93 gravitational waves reported in the GWTC-3 catalog were analyzed and no statistically significant excess over the background was observed. As a result, the strongest upper limits on GW-associated neutrino and antineutrino fluences for all flavors ( Formula omitted) at the level Formula omitted have been obtained in the 0.5-5 MeV neutrino energy range.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
IMPORTANCE: Cannabis and cannabinoid drugs are widely used to treat disease or alleviate symptoms, but their efficacy for specific indications is not clear. OBJECTIVE: To conduct a systematic review ...of the benefits and adverse events (AEs) of cannabinoids. DATA SOURCES: Twenty-eight databases from inception to April 2015. STUDY SELECTION: Randomized clinical trials of cannabinoids for the following indications: nausea and vomiting due to chemotherapy, appetite stimulation in HIV/AIDS, chronic pain, spasticity due to multiple sclerosis or paraplegia, depression, anxiety disorder, sleep disorder, psychosis, glaucoma, or Tourette syndrome. DATA EXTRACTION AND SYNTHESIS: Study quality was assessed using the Cochrane risk of bias tool. All review stages were conducted independently by 2 reviewers. Where possible, data were pooled using random-effects meta-analysis. MAIN OUTCOMES AND MEASURES: Patient-relevant/disease-specific outcomes, activities of daily living, quality of life, global impression of change, and AEs. RESULTS: A total of 79 trials (6462 participants) were included; 4 were judged at low risk of bias. Most trials showed improvement in symptoms associated with cannabinoids but these associations did not reach statistical significance in all trials. Compared with placebo, cannabinoids were associated with a greater average number of patients showing a complete nausea and vomiting response (47% vs 20%; odds ratio OR, 3.82 95% CI, 1.55-9.42; 3 trials), reduction in pain (37% vs 31%; OR, 1.41 95% CI, 0.99-2.00; 8 trials), a greater average reduction in numerical rating scale pain assessment (on a 0-10-point scale; weighted mean difference WMD, −0.46 95% CI, −0.80 to −0.11; 6 trials), and average reduction in the Ashworth spasticity scale (WMD, −0.12 95% CI, −0.24 to 0.01; 5 trials). There was an increased risk of short-term AEs with cannabinoids, including serious AEs. Common AEs included dizziness, dry mouth, nausea, fatigue, somnolence, euphoria, vomiting, disorientation, drowsiness, confusion, loss of balance, and hallucination. CONCLUSIONS AND RELEVANCE: There was moderate-quality evidence to support the use of cannabinoids for the treatment of chronic pain and spasticity. There was low-quality evidence suggesting that cannabinoids were associated with improvements in nausea and vomiting due to chemotherapy, weight gain in HIV infection, sleep disorders, and Tourette syndrome. Cannabinoids were associated with an increased risk of short-term AEs.
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 %.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Since the beginning of 2012, the Borexino collaboration has been reporting precision measurements of the solar neutrino fluxes, emitted in the proton–proton chain and in the Carbon–Nitrogen–Oxygen ...cycle. The experimental sensitivity achieved in Phase-II and Phase-III of the Borexino data taking made it possible to detect the annual modulation of the solar neutrino interaction rate due to the eccentricity of Earth’s orbit, with a statistical significance greater than 5σ. This is the first precise measurement of the Earth’s orbital parameters based solely on solar neutrinos and an additional signature of the solar origin of the Borexino signal. The complete periodogram of the time series of the Borexino solar neutrino detection rate is also reported, exploring frequencies between one cycle/year and one cycle/day. No other significant modulation frequencies are found. The present results were uniquely made possible by Borexino’s decade-long high-precision solar neutrino detection.
This work intends to be a starting point for the extension of the TRANSURANUS fuel rod performance code to the modelling of the T91 steel, which is designed to be the cladding material in LBE ...(lead-bismuth eutectic) accelerator-driven systems (ADS). On the basis of the experimental data available in the recent literature on LBE and T91, a preliminary modelling of the T91 corrosion with flowing LBE under oxygen control is proposed, and the main issues (i.e., heat transfer, creep, swelling) relevant for the performance of this steel in a reactor are discussed, in order to be properly considered in TRANSURANUS.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The search for neutrino events in correlation with 42 most intense fast radio bursts (FRBs) has been performed using the Borexino dataset from 05/2007 to 06/2021. We have searched for signals with ...visible energies above 250 keV within a time window of
±
1000
s corresponding to detection time of a particular FRB. We also applied an alternative approach based on searching for specific shapes of neutrino-electron scattering spectra in the full exposure data of the Borexino detector. In particular, two incoming neutrino spectra were considered: the monoenergetic line and the spectrum expected from supernovae. The same spectra were considered for electron antineutrinos detected through inverse beta-decay reaction. No statistically significant excess over the background was observed. As a result, the strongest upper limits on FRB-associated neutrino fluences of all flavors have been obtained in the 0.5–50 MeV neutrino energy range.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cosmogenic radio-nuclei are an important source of background for low-energy neutrino experiments. In Borexino, cosmogenic
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
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
C tagging efficiency of
∼
90
% and
∼
63–66 % of the exposure surviving the tagging. We present also a novel technique that targets specifically
11
C produced in high-multiplicity during major spallation events. Such
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
∼
90
%
but with a higher fraction of the exposure surviving, in the range of
∼
66–68 %.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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 %.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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