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Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev- Smirnov-Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the recent experimental result about the large mixing angle 013 (-8.8°) provided by the Daya Bay Collaboration and applying the available knowledge for the neutrino conversion probability in the high resonance region of SN, PH , which is in the form of hypergeometric function in the case of large 813, we deduce the expression of PH taking into account the shock wave effects. It is found that PH is not zero in a certain range of time due to the shock wave effects. After considering all the four physical effects and scanning relevant parameters, we calculate the event numbers of SN neutrinos for the "Garehing" distribution of neutrino energy spectrum. From the numerical results, it is found that the behaviors of neutrino event numbers detected on the Earth depend on the neutrino mass hierarchy and neutrino spectrum parameters including the dimensionless pinching parameter βa (where a refers to neutrino flavor), the average energy 〈Ea〉, and the SN neutrino luminosities La. Finally, we give the ranges of SN neutrino event numbers that will be detected at the Daya Bay experiment. 相似文献
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《中国物理C(英文版)》2018,(11)
It is known that in supernova explosions, there might be a reverse shock wave in addition to the forward shock wave during the explosion phase, when the mass of supernova is in a certain range. In this paper, we propose to add the reverse shock wave to the previous supernova model, in which only the forward shock wave was included,and thus obtain a new model. By analyzing the resonance condition as well as the density jump in the new model and using the Landau-Zener method, an expression for the crossing probability in high density matter(PH) is given.We proceed to study how PH varies with time and with neutrino energy when both the reverse shock wave and the forward shock wave are considered. From comparison with the previous results, where only the effects of the forward shock wave were considered, it is clear that the reverse shock wave brings significant changes to PH. 相似文献
4.
We generalize our virial approach to study spin-polarized neutron matter and the consistent neutrino response at low densities. In the long-wavelength limit, the virial expansion makes model-independent predictions for the density and spin response, based only on nucleon–nucleon scattering data. Our results for the neutrino response provide constraints for random-phase approximation or other model calculations, and we compare the virial vector and axial response to response functions used in supernova simulations. The virial expansion is suitable to describe matter near the supernova neutrinosphere, and this work extends the virial equation of state to predict neutrino interactions in neutron matter. 相似文献
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After considering supernova shock effects, Mikheyev-Smirnov-Wolfenstein effects, neutrino collective effects, and Earth matter effects, the detection of supernova neutrinos at the China Spallation Neutron Source is studied and the expected numbers of different flavor supernova neutrinos observed through various reaction channels are calculated with the neutrino energy spectra described by the Fermi-Dirac distribution and the "beta fit"distribution respectively. Furthermore, the numerical calculation method of supernova neutrino detection on Earth is applied to some other spallation neutron sources, and the total expected numbers of supernova neutrinos observed through different reactions channels are given. 相似文献
6.
P. Astier G. Bernardi G. Carugno J. Chauveau P. Chrysicopoulou J. Dumarchez M. Ferro-Luzzi F. Kovacs A. Letessier-Selvon J. -M. Levy M. J. Murtagh J. -M. Perreau Y. Pons J. L. Stone A. -M. Touchard F. Vannucci P. Wanderer D. H. White 《Physics letters. [Part B]》1989,220(4):646-652
A search for νμ→νe and
oscillations has been conducted with the AGS wide-band neutrino beam at the Brookhaven National Laboratory. We find more νe (
e) interactions than were expected on the basis of the number of incident νe (
e) calculated as part of the neutrino beam. The excess is about a factor two over the expectation, the statistical significance being about two and a half standard deviations for νe and weaker for
e. 相似文献
7.
LAI Xiang-Jun LUO Zhi-Quan LIU Jing-Jing LIU Hong-Lin 《理论物理通讯》2008,49(6):1643-1648
The effect of quark interactions perturbatively to order αc on the conversion, from quark matter to strange quark matter, is studied systematically based on a recent set of current quark masses. The process has a significant effect on increasing the core temperature, the neutrino abundance and the neutrino energies even if there is no quark interaction. Furthermore, with the switch of the strong interaction among quarks, these quantities will increase respectively to some further extents with αc increase. Taking αc = 0.47 as an example, the temperature, the neutrino abundance and the total neutrino energies are further raised by about 10%, 7%, and 20% respectively, which is weakly dependent on the initial temperature. Combining the effect of the current quark mass and the effect of the quark strong interaction, the results of the conversions will greatly enhance the probability of success for a supernova explosion and deeply influence the dynamics of the supernova evolution. 相似文献
8.
在利用大亚湾中微子实验装置研究超新星中微子探测过程中, 需要考虑到中微子传播过程中受到各种效应的影响, 包括超新星震荡效应、中微子集体效应、 Mikheyev Smirnov Wolfenstein (MSW)效应和地球物质效应等。 由于超新星中微子受到这些效应, 不同味道的中微子之间振荡会发生变化, 因而利用探测某些超新星中微子事例数之比, 就有可能确定中微子的质量层次,得到中微子混合角θ13和中微子绝对质量的信息。 While detecting supernova neutrinos in the Daya Bay neutrino laboratory, several supernova neutrino effects need to be considered, including the supernova shock effects, the neutrino collective effects, the Mikheyev Smirnov Wolfenstein (MSW) effects, and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos, we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses. 相似文献
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M. I. Krivoruchenko D. K. Nadyozhin T. L. Rasinkova Yu. A. Simonov M. A. Trusov A. V. Yudin 《Physics of Atomic Nuclei》2011,74(3):371-412
Phase transition from hadronic matter to quark-gluon matter is discussed for various regimes of temperature and baryon number
density. For small and medium densities, the phase transition is accurately described in the framework of the Field Correlation
Method, whereas at high density predictions are less certain and leave room for the phenomenological models. We study formation
of multiquark states (MQS) at zero temperature and high density. Relevant MQS components of the nuclear matter can be described
using a previously developed formalism of the quark compound bags (QCB). Partialwave analysis of nucleon-nucleon scattering
indicates the existence of 6QS which manifest themselves as poles of P matrix. In the framework of the QCB model, we formulate a self-consistent system of coupled equations for the nucleon and
6QS propagators in nuclear matter and the G matrix. The approach provides a link between high-density nuclear matter with the MQS components and the cumulative effect
observed in reactions on the nuclei, which requires the admixture of MQS in the wave functions of nuclei kinematically. 6QS
determines the natural scale of the density for a possible phase transition into theMQS phase of nuclear matter. Such a phase
transition can lead to dynamic instability of newly born protoneutron stars and dramatically affect the dynamics of supernovae.
Numerical simulations show that the phase transition may be a good remedy for the triggering supernova explosions in the spherically
symmetric supernovamodels. A specific signature of the phase transition is an additional neutrino peak in the neutrino light
curve. For a Galactic core-collapse supernova, such a peak could be resolved by the present neutrino detectors. The possibility
of extracting the parameters of the phase of transition from observation of the neutrino signal is discussed also. 相似文献
11.
The Earth effects on the energy spectra of supernova neutrinos are studied. We analyze numerically the time-integrated energy spectra of neutrino in a mantle–core–mantle step function model of the Earth's matter density profile. We consider a realistic frame-work in which there are three active neutrinos whose mass squared differences and mixings are constrained by the present understanding of solar and atmospheric neutrinos. We find that the energy spectra change for some allowed mixing parameters. Especially, the expected number of events at SNO shows characteristic behavior with respect to energy, i.e., a great dip and peak. We show that observations of the Earth effect allow us to identify the solar neutrino solution and to probe the mixing angle θ2. 相似文献
12.
T. Fischer D. Blaschke M. Hempel T. Kl?hn R. ?astowiecki M. Liebend?rfer G. Martínez-Pinedo G. Pagliara I. Sagert F. Sandin J. Schaffner-Bielich S. Typel 《Physics of Atomic Nuclei》2012,75(5):613-620
We compare two classes of hybrid equations of state with a hadron-to-quark matter phase transition in their application to core collapse supernova simulations. The first one uses the quark bag model and describes the transition to three-flavor quark matter at low critical densities. The second one employs a Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with parameters describing a phase transition to two-flavor quark matter at higher critical densities. These models possess a distinctly different temperature dependence of their transition densities which turns out to be crucial for the possible appearance of quark matter in supernova cores. During the early post-bounce accretion phase quark matter is found only if the phase transition takes place at sufficiently low densities as in the study based on the bag model. The increase critical density with increasing temperature, as obtained for our PNJL parametrization, prevents the formation of quark matter. The further evolution of the core collapse supernova as obtained applying the quark bag model leads to a structural reconfiguration of the central protoneutron star where, in addition to a massive pure quark matter core, a strong hydrodynamic shock wave forms and a second neutrino burst is released during the shock propagation across the neutrinospheres. We discuss the severe constraints in the freedom of choice of quark matter models and their parametrization due to the recently observed 2M ?? pulsar and their implications for further studies of core collapse supernovae in the QCD phase diagram. 相似文献
13.
Effects of inelastic neutrino-nucleus scattering on supernova dynamics and radiated neutrino spectra
Langanke K Martínez-Pinedo G Müller B Janka HT Marek A Hix WR Juodagalvis A Sampaio JM 《Physical review letters》2008,100(1):011101
Based on the shell model for Gamow-Teller and the random phase approximation for forbidden transitions, we calculate cross sections for inelastic neutrino-nucleus scattering (INNS) under supernova (SN) conditions, assuming a matter composition given by nuclear statistical equilibrium. The cross sections are incorporated into state-of-the-art stellar core-collapse simulations with detailed energy-dependent neutrino transport. While no significant effect on the SN dynamics is observed, INNS increases the neutrino opacities noticeably and strongly reduces the high-energy tail of the neutrino spectrum emitted in the neutrino burst at shock breakout. Relatedly the expected event rates for the observation of such neutrinos by earthbound detectors are reduced by up to about 60%. 相似文献
14.
《Physics letters. [Part B]》1997,406(4):355-365
A general exact analytic expression for the probability of matter-enhanced two-neutrino transitions in a medium (MSW, RSFP, generated by neutrino FCNC interactions, etc.) is derived. The probability is expressed in terms of three real functions of the parameters of the transitions: the “jump” probability and two phases (angles). The results obtained can be utilized, in particular, in the studies of the matter-enhanced transitions/conversions of solar and supernova neutrinos. An interesting similarity between the Schroedinger equation for the radial part of the non-relativistic wave function of the hydrogen atom and the equation governing the MSW transitions of solar neutrinos in the exponentially varying matter density in the Sun is also briefly discussed. 相似文献
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Ramachandran K. Tripathi V.K. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(3):423-426
A long wavelength Langmuir wave (ω0, k0), propagating through a parabolic plasma density channel, can decay into a low-frequency mode (ω,k&oarr;) and two short wavelength Langmuir wave sidebands (ν1,2,k&oarr;1,2 ), via two-stream instability where ω1,2=ω∓ω0 and k&oarr;1,2=k&oarr;∓k&oarr;0. Depending on the mode number n, the growth rate maximizes in the range γmax≃0.1ωpi-0.4ωpi for the range of k from 0.1(ωpi/cs) to 0.2(ωpi/cx) for ν0~νth where ν0 and νth are the oscillatory and thermal velocities of electrons, ωpi is the ion plasma frequency on the axis, and cs is the sound speed. The growth rate increases with the width a of the plasma density channel. It decreases with the mode number. The instability may be relevant to laser based charged particle accelerators 相似文献
17.
A. Nicolaidis 《Physics letters. [Part B]》1988,200(4):553-559
The Mikheyev-Smirnov-Wolfenstein solution to the solar-neutrino deficit provides a range for the acceptable neutrino parameters (Δm2 and sin 2θ0). If the vacuum mixing angle θ0 is not too small, the resulting neutrino oscillation length in matter is comparable to the radius of the earth. For such appropriate neutrino parameters we study neutrino oscillations inside the earth. The core of the earth is taken as a sphere with constant density 11 g/cm3, while the mantle, surrounding the core, is taken to be a spherically symmetric shell of constant density 4.4 g/cm3. We obtain an exact, analytic expression for the probability that an electron-neutrino after traversing the earth, emerges as an electron-neutrino. Our results indicate that the neutrinos might serve as the ideal tools for earth tomography. 相似文献
18.
In this paper, we compute the next-nearest-neighbouring site percolation (Connections exist not only between nearest-neighbouring sites, but also between next-nearest-neigh bouring sites.) probabilities PC on the two-dimensional Sierpinski carpets, using the translationaldilation method and Monte Carlo technique. We obtain a relation among PC, fractal dimensionality D and connectivity Q. For the family of carpets with central cutouts,(1 - Pc)/(1 - Pcs) = (D - 1)1.60, where Pcs = 0.41, the critical percolation probability for the next-nearest-neighbouring site problem on square lattice. As D reaches 2, Pc = Pcs = 0.41, which is in agreement with the critical percolation probability on 2-d square lattices with . next-nearest-neigh bouring interactions. 相似文献
19.
In this paper, we discuss the evolution operator and the transition probabilities expressed as functions of the vacuum mass
squared differences, the vacuum mixing angles, and the matter density parameter for three flavor neutrino oscillations in
matter of varying density in the plane wave approximation. The applications of this to neutrino oscillations in a model of
the earth's matter density profile, step function matter density profiles, constant matter density profiles, linear matter
density profiles, and finally in a model of the sun's matter density profile are discussed. We show that for matter density
profiles which do not fluctuate too much, the total evolution operator consisting of n operators can be replaced by one single evolution operator in the semi-classical approximation.
Received: 23 March 2001 / Published online: 8 June 2001 相似文献
20.
High energy neutrino bremsstrahlung ν → ν + γ in a strong magnetic field (B Bs) is studied in the framework of the Standard Model (SM). A resonance probability and a four-vector of the neutrino energy and momentum loss are presented. A possible manifestation of the neutrino bremsstrahlung in astrophysical cataclysm of type of a supernova explosion or a merger of neutron stars, as an origin of cosmological γ-burst is briefly discussed. 相似文献