scholarly journals Atmospheric muon and electron neutrino energy spectrum measured by first year of IceCube-86 detector

2016 ◽  
Author(s):  
Takao Kuwabara
2009 ◽  
Vol 24 (11n13) ◽  
pp. 1051-1054
Author(s):  
UNGKU FERWANI SALWA UNGKU IBRAHIM ◽  
NOR SOFIAH AHMAD ◽  
NORHASLIZA YUSOF ◽  
HASAN ABU KASSIM

Neutrinos are produced copiously in the early universe. Neutrinos and antineutrinos ceased to be in equilibrium with radiation when the weak interaction rate becomes slower than the rate expansion of the universe. The ratio of the temperature of the photon to the temperature of the neutrino at this stage is Tγ/Tν = (11/4)1/3. We investigate the neutrino energy loss due to the oscillation of the electron neutrino into a different flavor in the charged-current interaction of νe-e- based on the work of Sulaksono and Simanjuntak. The energy loss from the neutrinos ΔEν during the decoupling of the neutrinos with the rest of the matter would be a gain in the energy of the electrons and can be obtained from the integration of stopping power equation ΔEν = (dEν/dT-1)dT-1 where Eν and T are the energy of the neutrinos and the temperature respectively. When the universe expands and matter-radiation decouples, an extra energy will be transferred to the photons via the annihilation of the electron-positron pairs, e++e-→γ+γ. This consequently will increase the temperature of the photons. The net effect to the lowest order is an increase in the ratio of the photon temperature to the neutrino temperature. The magnitude of energy loss of the neutrino is ∼10-4-10-5 MeV for the probability of conversion of νe → νi (i = μ,τ) between 0 to 1.0.


2004 ◽  
Vol 13 (05) ◽  
pp. 831-841 ◽  
Author(s):  
DANIELA KIRILOVA

We study the distortion of electron neutrino energy spectrum due to oscillations with the sterile neutrino νe↔νs, for different initial populations of the sterile state δNs at the onset of oscillations. The influence of this spectrum distortion on Big Bang Nucleosynthesis is analyzed. Only the case of an initially empty sterile state was studied in previous publications. The primordial abundance of 4He is calculated for all possible δNs:0≤δNs≤1 in the model of oscillations, effective after electron neutrino decoupling, for which the spectrum distortion effects on the neutron–proton transitions are the strongest. It is found that the spectrum distortion effect may be dominant, not only in the case of small δNs, but also in the case of large initial population of νs. For example, in the resonant case it may play a considerable role even for very large δNs~0.8. Cosmological constraints on neutrino mixing for small δNs are discussed.


2005 ◽  
Vol 20 (14) ◽  
pp. 3055-3058
Author(s):  
◽  
RICHARD GRAN

The K2K long-baseline neutrino oscillation experiment has analyzed all data including the period ending in February 2004. The total data sample is from 8.9 × 1019 protons on target. We observe 108 events at the far detector, Super-Kamiokande, when 150.9 + 11.6 - 10.0 were expected. Further, we observe a distortion of the neutrino energy spectrum which is consistent with νμ to ντ oscillation. The probability that we would observe these results if there is no neutrino oscillation is 0.011%, a 3.9 σ significance.


2021 ◽  
Vol 81 (5) ◽  
Author(s):  
B. Abi ◽  
R. Acciarri ◽  
M. A. Acero ◽  
G. Adamov ◽  
D. Adams ◽  
...  

AbstractThe deep underground neutrino experiment (DUNE), a 40-kton underground liquid argon time projection chamber experiment, will be sensitive to the electron-neutrino flavor component of the burst of neutrinos expected from the next Galactic core-collapse supernova. Such an observation will bring unique insight into the astrophysics of core collapse as well as into the properties of neutrinos. The general capabilities of DUNE for neutrino detection in the relevant few- to few-tens-of-MeV neutrino energy range will be described. As an example, DUNE’s ability to constrain the $$\nu _e$$ ν e spectral parameters of the neutrino burst will be considered.


2011 ◽  
Vol 83 (1) ◽  
Author(s):  
R. Abbasi ◽  
Y. Abdou ◽  
T. Abu-Zayyad ◽  
J. Adams ◽  
J. A. Aguilar ◽  
...  

1999 ◽  
Vol 82 (12) ◽  
pp. 2430-2434 ◽  
Author(s):  
Y. Fukuda ◽  
T. Hayakawa ◽  
E. Ichihara ◽  
K. Inoue ◽  
K. Ishihara ◽  
...  

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