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1.
Charge properties of the hadronic systems from νp and νp scattering in BEBC are studied in the framework of the quark-parto model (QPM). The average charges 〈Qjetν and 〈Qjetν of a quark jet and a d-qua jet, respectively, are determined according to two different methods. The difference 〈Qjetν ? 〈Qjetν is in agreement with e QPM value of 1. Scaling of charge and energy flow in the angular variable λ is demonstrated. The ratios ΔQν/ΔQν of charge flows in νp a νp scattering are in accord with the QPM in both hemispheres.  相似文献   

2.
We distinguish electron and positron tracks from νe and νe charged-current interactions in a large bubble chamber f ed with a neon-hydrogen mixture. No evidence is seen for an excess of νe interactions from primary νe sources secondary νμνeorνeνe oscillations. Upper limits on oscillation parameters, majoron sion and lepton-number violating π and K decays are presented.  相似文献   

3.
Inverse Compton scattering of low energy photons in a nonrelativistic electron gas is considered. The angle dependence in the Thomson cross section is neglected and spatial and energy transport are separated in a multiple scattering development of the emerging spectrum. The energy transport is determined by a Green function G which may be obtained from the single scattering spectrum for small optical depth or from the Kompaneets equation in the optically thick medium (τ ? 1). The electron cloud is assumed to be spherical and homogeneous with constant temperature ?e = kTemec2. Photon escape probabilities PN from the cloud after N scatterings are calculated from a random flight problem with absorbing walls and alternative methods are mentioned and compared in the limit of large optical depth.  相似文献   

4.
A modified Kuti-Weisskopf model which satisfies the Feynman threshold constraints is considered further. Detailed predictions for the sum of neutrino and anti-neutrino differential cross sections on nucleon (which can be readily compared with forthcoming NAL data), the shapes of the structure functions ?2νp,νn and the ratio ?2νp/?2νn, and spin-dependence of inelastic electron-nucleon scattering versus scaling variable x are delineated. We also compare in some detail the general features of our model with the “model independent” approach of Feynman for quark parton theory.  相似文献   

5.
The apparent absence of the decay τ → ντν?1?, where ? = e or μ andνi is the spin-zero supersymmetric partner of νi, implies that the νi masses are sufficiently large that the decay is suppressed (assuming the supersymmetric partners exist). We give the resulting limits, which depend on the mass of the W? (the supersymmetric partner of the W) which mediates the decay, and on whether one or both ν is massive. These are the only experimental limits on ν masses.  相似文献   

6.
A comprehensive approach of the simultaneous analysis of several complex vibrational polyads in polyatomic molecules is presented. Specific points regarding theoretical models and weighted least-squares procedures are discussed with the aim of determining a unique set of parameter values for reproducing all available data on a given molecule. The simultaneous analysis of the dyad ν2ν5 and the pentad ν14/2ν22 + ν55 of 12CH3F using microwave and infrared data is reported as an illustration.  相似文献   

7.
We present a unified gauge theory of weak and electromagnetic interactions in which parity is spontaneously broken together with gauge invariance, by the Higgs mechanism. The gauge group is SU(2) × U(1), and a heavy neutrino is associated with every charged lepton. After the breaking of the original parity-conserving theory, both a purely vector electromagnetic current and the usual V-A charged currents are obtained. Z is coupled to a vector electron current, and the model predicts equal νμe andνμe cross sections. Extension to hadrons is made by introducing three charmed quarks p′, n′ and λ′ of the same charges as p, n and λ. All the experimental results μe, νμe, νee, νμ and νμ hadron scatterings) are compatible with a value of sin2θW of order 0.4.  相似文献   

8.
Using a solution to the inverse scattering problem we have generated phase-equivalent separable potentials in the 1S0 and 3S1?3D1 states, which have nearly the same singlet UPA form factors and deuteron parameters (ED, PD, QD, AS and ADAS) as the Reid soft-core potential. We compare our results for the binding energy of the triton and the neutron-deuteron doublet scattering length with the corresponding values for the Reid soft-core potential.  相似文献   

9.
The possibility is considered that in the neutral current reactions ν+ target → ν′ + …, the final neutrino ν′ may be distinct from the initial neutrino ν. A test of neutrino identity is proposed based on the scattering of low energy (reactor) antineutrinos νe from an electron target.  相似文献   

10.
We investigate transition strengths of right-handed weak charged currents in deep inelastic neutrino scattering, exploiting the dominance of p, n valence quarks in the nucleon. The energy dependence of σt and the average quantities 〈y〉 and 〈Q2〉 are shown to provide sensitive measures of new quark production thresholds and right-handed currents in νN scattering. With our analysis, the present data give an upper bound on the right to left hand structure function ratio of FRνNFLνN12, above a threshold of W≈7.5 GeV.  相似文献   

11.
We derive and compare with experimental data the bound
α??λmp?mpν212ν0dν′σtot(ν′)(ν′221)+2πmpν0ν′2dν′σtot(ν′)(ν′221){ν′2(dσdt)0+πλ2+2ν′|λ|π(dσdt)0?σ2tot16π}?1
, where α is the fine-structure constant, mp the proton mass, ν0 the photo-pion production threshold, σtot and (dσdt)0 are the unpolarized total hadronic photo-absorption cross section on protons and the unpolarized forward differential cross section for proton Compton scattering at photon-lab energy ν′, and λ and ν1 are any real numbers. We derive similar bounds on proton and neutron magnetic moments.  相似文献   

12.
Benzoyl fluoride exhibits a weak, discrete absorption system in the region 290 – 260 nm. Vibrational structure associated with the C6H5COF and C6D5COF isotopes has been analyzed in detail. The C6H5COF and C6D5COF origin bands lie at 35 685 and 35 829 cm?1, respectively. The intensity in the spectrum is principally associated with two progressions, ν19, the breathing vibration of the benzene ring and ν24, a COF in-plane bend, and sequence bands involving the COF torsion motion ν36. The C6H5COFC6D5COFν19, ν24, and ν36 vibrational frequencies are respectively 1005/-, 376357, and 5755 cm?1 in the ground state and 950919, 348331, and 8985 cm?1 in the excited state. The barriers to rotation of the COF group are estimated from the torsional frequency data to be 1450 and 3450 cm?1 in the ground and excited electronic states, respectively.  相似文献   

13.
The Raman active fundamentals ν1(A1g), ν2(Eg), ν5(F2g), and the overtone 2ν6 of SF6 have been investigated with a higher resolution and the band origins were estimated to be: ν1 = 774.53 cm?1, ν2 = 643.35 cm?1, ν5 = 523.5 cm?1, and 2ν6 = 693.8 cm?1. Raman and infrared data have been combined for estimation of several anharmonicity constants. The ν6 fundamental frequency is calculated as 347.0 cm?1. From the analysis of the ν2 Raman band, the following rotational constants of both the ground and upper states have been calculated:
B0 = 0.09111 ± 0.00005cm?1; D0 = (0.16±0.08)10?7cm?1
;
B2 = 0.09116 ± 0.00005cm?1; D2 = (0.18±0.04)10?7cm?1
.  相似文献   

14.
The high-energy pire-leptonic weak interaction is investigated based on the assumption of the existence of a charged vector boson which mediates the weak processes. With the aid of the fixed-t dispersion relation the following relation is obtained: The weak boson mass mW should satisfy mW? G?12, with G the Fermi coupling constant, if the asymptotic value of the cross section becomes of the order of the strong interaction in the energy region observable in cosmic rays, etc.The scattering processes e+ν→eande+νe+ν are examined by the aid of the N/D method. For a large vector-boson mass mW?100 GeV, an S-wave resonance should exist for the process e+ν→e+ν while for e+νe+ν there should exist a P-wave resonance which corresponds to the intermediate weak boson. The neutral current is then estimated. It is shown that the neutral current produced as a higher-order effect is not inconsistent with the present experiments on the pure-leptonic weak interaction if mW?1 TeV.  相似文献   

15.
The Coriolis resonance between ν4 and ν7 in CH3CN and between ν1 and ν5, ν3 and ν6, and ν4 and ν7 in CD3CN has been analyzed, applying the technique developed by DiLauro and Mills, to obtain the signs of [ζr,say(?p?Qr)(?p?Qsa)] and the ratio of ?Qr to ?Qs for the interacting pairs in CD3CN. For (ν4, ν7) in both CH3CN and CD3CN, the sign of [ζr,say(?p?Qr)(?p?Qsa)] is found to be negative as it is also for (ν1, ν5) in CD3CN. For (ν3, ν6) the sign of this interaction term is found to be positive. For a given definition of normal coordinates the signs of these interaction terms give the relative signs of ?p?Qr and ?p?Qsa; our study also gives approximate values for the corresponding ratio [(?p?Qr)(?p?Qsa)]  相似文献   

16.
In the presence of neutral lepton currents, the characteristics of the reaction νμ(νμ) + Z → νμ(νμ) + μ? + μ+ + Z are modified from those expected in the conventional V-A theory. We show that in a very general class of intermediate boson theories, the modification produced can be specified entirely in terms of the cross sections for νμ(νμ) + e? → νμ(νμ) + e?. Such a constraint does not necessarily exist in models with four-fermion interaction.  相似文献   

17.
The propagation of the surface acoustic mode in the (001) plane is investigated as a function of the temperature dependent elastic moduli of Nb3Sn in the cubic phase. For the [100] and [110]-directions a softening of the surface mode velocity νs is found to follow the softening of the velocity νT2 of the bulk shear mode T2A. It is shown that for the [100]-direction the ratio (νsνT2) tends to ?2 at the structural phase transition. The question is discussed of whether the softening of the surface mode can be observed with Brillouin scattering from opaque surfaces.  相似文献   

18.
We propose a unified explanation of charged and neutral current neutrino scattering data, based on a minimal model with 3 quark and 3 lepton doublets. The data force a unique p and n quark doublet structure. Our inclusive neutral current predictions for sin2 θW = 38 are identical to the Weinberg-Salam model, but our νpνp predictions agree better with experiment. We make predictions for ν?p→ν?p, predictions physics, supernova explosions, and ψ →νν? decay.  相似文献   

19.
Eight P-branch transitions from the ν5141 difference band of C2D2 have been observed in the microwave region. Significant improvements in the spectroscopic constants for the two states involved in the difference band have been obtained by combining infrared and microwave data. The Stark shifts for the observed C2D2 lines are discussed in some detail. The vibrational transition moment is found to be μvib = 0.0358 ± 0.0020 D.  相似文献   

20.
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