Search results for " Neutrino"
showing 10 items of 727 documents
Beta-decay of light nuclei close to the proton drip-line: 40Ti and 35Ca
1998
The s-decay of40Ti and35Ca have been studied at the LISE3 spectrometer at GANIL. The decay schemes were deduced from the observed s-delayed proton and γ emission of40Ti and35Ca into the ground and first excited states of39Ca and34Ar, respectively. The Gamow-Teller strength functionB(GT) of the40Ti s-decay extracted from the s-decay branching ratios and the precisely measured40Ti half-life, provides for the first time an experimental calibration of the neutrino detection efficiency for the ICARUS solar neutrino detector.
Isocurvature Constraints on Portal Couplings
2016
We consider portal models which are ultraweakly coupled with the Standard Model, and confront them with observational constraints on dark matter abundance and isocurvature perturbations. We assume the hidden sector to contain a real singlet scalar $s$ and a sterile neutrino $\psi$ coupled to $s$ via a pseudoscalar Yukawa term. During inflation, a primordial condensate consisting of the singlet scalar $s$ is generated, and its contribution to the isocurvature perturbations is imprinted onto the dark matter abundance. We compute the total dark matter abundance including the contributions from condensate decay and nonthermal production from the Standard Model sector. We then use the Planck lim…
Resonance ionization spectroscopy for trace analysis and fundamental research
1994
Resonance ionization spectroscopy (RIS) and its combination with mass spectrometry (RIMS) have grown to become powerful techniques, which offer high sensitivity as well as elemental and isotopic selectivity. The principles of RIS and RIMS are introduced; they primarily concern the analysis of the optical spectra for the choice of efficient excitation schemes and the suitable design of the experimental apparatus. Recent applications span from studies of short-lived isotopes at on-line mass separators to a wide variety of trace analysis applications for radioactive isotopes, which can range from measurements of solar neutrino flux to environmental assessment.
Searches for small-scale anisotropies from neutrino point sources with three years of IceCube data
2015
Recently, IceCube found evidence for a diffuse signal of astrophysical neutrinos in an energy range of $60\,\mathrm{TeV}$ to the $\mathrm{PeV}$-scale. The origin of those events, being a key to understanding the origin of cosmic rays, is still an unsolved question. So far, analyses have not succeeded to resolve the diffuse signal into point-like sources. Searches including a maximum-likelihood-ratio test, based on the reconstructed directions and energies of the detected down- and up-going neutrino candidates, were also performed on IceCube data leading to the exclusion of bright point sources. In this paper, we present two methods to search for faint neutrino point sources in three years o…
Prospects for detecting the diffuse supernova neutrino background with JUNO
2022
We present the detection potential for the diffuse supernova neutrino background (DSNB) at the Jiangmen Underground Neutrino Observatory (JUNO), using the inverse-beta-decay (IBD) detection channel on free protons. We employ the latest information on the DSNB flux predictions, and investigate in detail the background and its reduction for the DSNB search at JUNO. The atmospheric neutrino induced neutral current (NC) background turns out to be the most critical background, whose uncertainty is carefully evaluated from both the spread of model predictions and an envisaged in situ measurement. We also make a careful study on the background suppression with the pulse shape discrimination (PSD) …
Feasibility and physics potential of detecting 8B solar neutrinos at JUNO
2021
The Jiangmen Underground Neutrino Observatory (JUNO) features a 20 kt multi-purpose underground liquid scintillator sphere as its main detector. Some of JUNO's features make it an excellent location for B-8 solar neutrino measurements, such as its low-energy threshold, high energy resolution compared with water Cherenkov detectors, and much larger target mass compared with previous liquid scintillator detectors. In this paper, we present a comprehensive assessment of JUNO's potential for detecting B solar neutrinos via the neutrino-electron elastic scattering process. A reduced 2 MeV threshold for the recoil electron energy is found to be achievable, assuming that the intrinsic radioactive …
Deep sea tests of a prototype of the KM3NeT digital optical module
2014
SIRE(opens in a new window)|View at Publisher| Export | Download | Add to List | More... European Physical Journal C Volume 74, Issue 9, 1 September 2014, 8p Deep sea tests of a prototype of the KM3NeT digital optical module: KM3NeT Collaboration (Article) Adrián-Martínez, S.a, Ageron, M.b, Aharonian, F.c, Aiello, S.d, Albert, A.e, Ameli, F.f, Anassontzis, E.G.g, Anghinolfi, M.h, Anton, G.i, Anvar, S.j, Ardid, M.a, de Asmundis, R.k, Balasi, K.l, Band, H.m, Barbarino, G.kn, Barbarito, E.o, Barbato, F.kn, Baret, B.p, Baron, S.p, Belias, A.lq, Berbee, E.m, van den Berg, A.M.r, Berkien, A.m, Bertin, V.b, Beurthey, S.b, van Beveren, V.m, Beverini, N.st, Biagi, S.uv, Bianucci, S.t, Billault, M.b,…
Cosmic ray composition and energy spectrum from 1–30 PeV using the 40-string configuration of IceTop and IceCube
2012
Astroparticle physics 42, 15 - 32 (2013). doi:10.1016/j.astropartphys.2012.11.003
Low-energy Neutrino Astronomy in LENA
2015
LENA (Low Energy Neutrino Astronomy) is a proposed next-generation neutrino detector based on 50 kilotons of liquid scintillator. The low detection threshold, good energy resolution and excellent background rejection inherent to the liquid-scintillator detectors make LENA a versatile observatory for low-energy neutrinos from astrophysical and terrestrial sources. In the framework of the European LAGUNA-LBNO design study, LENA is also considered as far detector for a very-long baseline neutrino beam from CERN to Pyhasalmi ¨ (Finland). The present contribution gives an overview LENA’s broad research program, highlighting the unique capabilities of liquid scintillator for the detection of low-…
Measurement of the group velocity of light in sea water at the ANTARES site
2012
The group velocity of light has been measured at eight different wavelengths between 385 nm and 532 nm in the Mediterranean Sea at a depth of about 2.2 km with the ANTARES optical beacon systems. A parametrisation of the dependence of the refractive index on wavelength based on the salinity, pressure and temperature of the sea water at the ANTARES site is in good agreement with these measurements.