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1.
From the assumption of symmetry of ratio of Fermion masses and masses of bosons ratio results the hypothetical mass of quark-lepton bosonm wes and hypothetical mass of electron neutrinom ve.  相似文献   

2.
On the basis of model properties of the expansive non-decelerative universe, the temperature at the end of the radiation era and of the present temperature of cosmic microwave background spectrum, the present parameters of our Universe can be determined.From model properties of the expansive non-decelerative universe and the temperature at the end of the radiation era follow: the hypothetical mass value of electron neutrino and the hypothetical values of the final parameters of the creative-expansive evolutionary phases of ultrastable expansive non-decelerative universes.  相似文献   

3.
We compare the tau neutrino flux arising from the galaxy and the earth atmosphere for 103E/GeV1011. The intrinsic and oscillated tau neutrino fluxes from both sources are calculated. The intrinsic galactic ντ flux (E103 GeV) is calculated by considering the interactions of high-energy cosmic-rays with the matter present in our galaxy, whereas the oscillated galactic ντ flux is coming from the oscillation of the galactic νμ flux. For the intrinsic atmospheric ντ flux, we extend the validity of a previous calculation from E106 GeV up to E1011 GeV. The oscillated atmospheric ντ flux is, on the other hand, rather suppressed. We find that, for 103E/GeV5×107, the oscillated ντ flux along the galactic plane dominates over the maximal intrinsic atmospheric ντ flux, i.e., the flux along the horizontal direction. We also briefly mention the presently envisaged prospects for observing these high-energy tau neutrinos.  相似文献   

4.
In the light of the experiments /3,4/ showing that neutrinos may have a non-zero rest-mass, we discuss the constraints placed on the cosmological term Λ and the Hubble constant Ho by such a mass and the age of the universe in the Lemaitre model. An upper limit of Λ of 15 × 10?57/cm2 and possible ranges of Ho are given.  相似文献   

5.
Cosmological and astrophysical measurements provide powerful constraints on neutrino masses complementary to those from accelerators and reactors. Here we provide a guide to these different probes, for each explaining its physical basis, underlying assumptions, current and future reach.  相似文献   

6.
The constraints on total neutrino mass and effective number of neutrino species based on CMB anisotropy power spectrum, Hubble constant, baryon acoustic oscillations and galaxy cluster mass function data are presented. It is shown that discrepancies between various cosmological data in Hubble constant and density fluctuation amplitude, measured in standard ΛCDM cosmological model, can be eliminated if more than standard effective number of neutrino species and non-zero total neutrino mass are considered. This extension of ΛCDM model appears to be ≈3σ significant when all cosmological data are used. The model with approximately one additional neutrino type, N eff ≈ 4, and with non-zero total neutrino mass, Σ ≈ 0.5 eV, provide the best fit to the data. In the model with only one massive neutrino the upper limits on neutrino mass are slightly relaxed. It is shown that these deviations from ΛCDM model appearmainly due to the usage of recent data on the observations of baryon acoustic oscillations. The larger than standard number of neutrino species is measured mainly due to the comparison of the BAO data with direct measurements of Hubble constant, which was already noticed earlier. As it is shown below, the data on galaxy cluster mass function in this case give the measurement of non-zero neutrino mass.  相似文献   

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Using cosmological data on the CMB anisotropy and large-scale structure of the Universe, we have obtained new constraints on the sum of the masses of three generations of active neutrinos: Σm ν < 1.05 eV (95% confidence level). Data of the third year of the WMAP mission served as the source of CMB anisotropy data. The mass functions of X-ray clusters of galaxies were taken as the data on the large-scale structure of the Universe. The observational properties of the clusters were obtained during the ROSAT mission and the assumption that the baryon fraction is universal in the Universe was used to determine the total cluster mass.  相似文献   

9.
The properties of the neutrino burst generated by massive 1.5–2M collapsing stellar iron-oxygen cores are discussed. Special attention is given to the neutrino heat conductivity theory which allows us to calculate the transport of neutrinos through the collapsing stellar core up to the formation and during the first seconds of cooling of a hot hydrostatic neutron star. The theoretical predictions seem to be in good agreement with both the KAMIOKANDE II and IMB data on the neutrino burst detected from SN 1987A. The most reliable constraint on the neutrino rest mass is shown to bem v <20–30eV, while the safest upper limit on the neutrino magnetic moment, µ v < 10–11 Bohr magnetons, results rather from the cooling of white dwarfs than from the SN 1987A neutrino data.Presented to the 13th International Conference Neutrino-88, Boston, U.S.A., 5–11 June, 1988.  相似文献   

10.
We consider cosmological models with dynamical dark energy (dDE) coupled to cold dark matter (CDM), while simultaneously allowing neutrinos to be massive. Using a MCMC approach, we compare these models with a wide range of cosmological data sets. We find a strong correlation between this coupling strength and the neutrino mass. This correlation persists when BAO data are included in the analysis. We add then priors on ν mass from particle experiments. The claimed detection of ν mass from the Heidelberg–Moscow neutrinoless double-β decay experiment would imply a 7–8σ detection of CDM–DE coupling. Similarly, the detection of ν mass from coming KATRIN tritium β decay experiment will imply a safe detection of a coupling in the dark sector. Previous attempts to accommodate cosmic phenomenology with such possible ν mass data made recourse to a w<-1 eoS. We compare such an option with the coupling option and find that the latter allows a drastic improvement.  相似文献   

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12.
The neutrino burst from Supernova 1987A detected by Mont Blanc, Kamiokande II, IMB, and BAKSAN have been studied by Jurkevich's mathematical technique of search for periodicities. It is found that all the data exhibit 11±0.2 ms period. There are also other periods, but they are almost exact multiples of 11 ms. We suggests that the 11 ms period is the pulsation period of the neutron core of the supernova remnant. From the observed period of neutrino data it is also possible to predict the masses of the neutrinos.  相似文献   

13.
In recent papers it was claimed that SN 1987A data supports the existence of 4.0 eV and 21.4 eV active neutrino mass eigenstates, and it was suggested that such large active neutrino masses could be made consistent with existing constraints including neutrino oscillation data and upper limits on the neutrino flavor state masses. The requirement was that there exist a pair of sterile neutrino mass states nearly degenerate with the active ones, plus a third active-sterile doublet that is tachyonic (m 2<0). Here, independent evidence is presented for the existence of sterile neutrinos with the previously claimed masses based on fits to the dark matter distributions in the Milky Way galaxy and four clusters of galaxies. The fits are in excellent agreement with observations within the uncertainties of the masses. In addition, sterile neutrinos having the suggested masses address the “cusp” problem and the missing satellites problem, as well as that of the “top down” scenario of structure formation—previously a chief drawback of HDM particles. Nevertheless, due to the highly controversial nature of the claim, and the need for two free parameters in the dark matter fits, additional confirming evidence will be required before it can be considered proven.  相似文献   

14.
An extensive 3-dimensional Monte Carlo calculation of the atmospheric neutrino flux is in progress with the FLUKA Monte Carlo code. The results are compared to those obtained under the 1-dimensional approximation, where secondary particles and decay products are assumed to be collinear to the primary cosmic ray, as usually done in most of the already existing flux calculations. It is shown that the collinear approximation gives rise to a wrong angular distribution of neutrinos, essentially in the Sub-GeV region. However, the angular smearing introduced by the experimental inability of detecting recoils in neutrino interactions with nuclei is large enough to wash out, in practice, most of the differences between 3-dimensional and 1-dimensional flux calculations. Therefore, the use of the collinear approximation should not have introduced a significant bias in the determination of the flavor oscillation parameters in current experiments.  相似文献   

15.
It is argued that the neutrino bursts registered on February 23.316 UT, 1987 signalized the transition of a fresh-borne neutron star into a superdense state. The neutron star is supposed to be formed approximately five hours before at February 23.12 UT in the supernova SN 1987a in the Large Magellanic Cloud.  相似文献   

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We analyze the influence of neutrino helicity conversion, ν Lν R, on the neutrino flux from a supernova attributable to the interaction of the Dirac neutrino magnetic moment with a magnetic field.We show that if the neutrino has a magnetic moment in the interval 10−13μB < μν < 10−12μB and provided that a magnetic field of ∼1013–1014 G exists in the supernova envelope, a peculiar kind of time evolution of the neutrino signal from the supernova attributable to the resonance transition ν Lν R in the magnetic field of the envelope can appear.  相似文献   

19.
The hypothetical final parameters of the Universe result from the model properties of the expansive non-decelerative universe and properties of the hypothetical primordial black holes.  相似文献   

20.
We present a new three-dimensional Monte-Carlo code MUSIC (MUon SImulation Code) for muon propagation through the rock. All processes of muon interaction with matter with high energy loss (including the knock-on electron production) are treated as stochastic processes. The angular deviation and lateral displacement of muons due to multiple scattering, as well as bremsstrahlung, pair production and inelastic scattering are taken into account. The code has been applied to obtain the energy distribution and angular and lateral deviations of single muons at different depths underground. The muon multiplicity distributions obtained with MUSIC and CORSIKA (Extensive Air Shower simulation code) are also presented. We discuss the systematic uncertainties of the results due to different muon bremsstrahlung cross-sections.  相似文献   

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