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1.
The reactions pp → pp and pp → Δ++n with polarized beam and/or polarized target are currently under investigation at the Argonne ZGS. We discuss how to interpret various measured quantities in terms of amplitudes whose behavior is familiar (as functions of s, t). For pp total cross sections and elastic scattering, Argonne measurements will yield Im ?2 (s,t = 0) and the rather complicated combination 2|?5|2 + Re (?1?21 ? ?3?41), where ?i (i = 1, … 5) are conventional s-channel helicity amplitudes. The forward direction (t = 0) is of special interest. We find that for both pp → pp and pp → Δ++n, polarized beam — polarized target experiments plus the rather general (testable) assumption that amplitudes with the same s-channel helicity flip quantum numbers are proportional, are sufficient to fully determine all non-vanishing amplitudes at t = 0. Numerical estimates of some observables, based on calculations in a specific model, are also given.  相似文献   

2.
A dispersion approach is suggested, based on the asymptotic freedom in QCD and on analyticity, which leads to sum rules for the amplitudes of radiative transitions in quarkonium (cc, bb, …) and allows one to estimate these amplitudes in a model-independent way. As an example such sum rules are derived for the 3P0 ? 3S1 and 3S1 ? 1S0 transitions. For charmonium they agree with the available data and with the predictions of nonrelativistic models.  相似文献   

3.
D.J. Gates 《Physica A》1975,81(1):47-71
The k-particle, infinite-volume distribution functions n?k (r1, …, rk?1, γ) and modified Ursell correlation functions U?k (r1, …, rk?1, γ) of a classical system of particles with the two-body potential q(r) + γνK(γr) are considered. The limiting values of the functions n?k (r1, …, rk?1, γ), n?k (S1/γ, …, Sk?1/γ, γ) and γ(1?kU?k (S1/γ, …, Sk?1/γ, γ) in the limit γ → 0 are calculated, under fairly weak conditions on q and K, by a method involving functional differentiation. These limiting functions are used to describe the molecular structure of the various states of the system both in the range of the potential q(r) and in the rage of the potential γνKr). The direct correlation function c? (r, γ) is also considered and it is shown that for S ≠ 0, limγ→0 γc? (Sγ, γ) = ?βK (S), for all one-phase states, where β is the reciprocal temperature. Special cases of our results confirm those of other authors, including the well-known results of Ornstein and Zernike.  相似文献   

4.
Let Ak be a self-adjoint operator in a Hilbert space Hk (k = 1, 2, …) and let L be an operator of the form L = Ar ? 1 ? 1 ? … + 1 ? A2 ? 1 ? 1 ? … + … acting in the infinite tensor product ?k=1 Hk. We construct the spectral theory of these operators. In particular, the expansion is generalized eigenvectors of this operator is constructed using the eigenvectors of the operators Ak.  相似文献   

5.
A set of normalized linearly independent basis functions φ1, φ2, …, φj, … generates matrix representatives H and N of the Hamiltonian operator and the identity. An orthonormal basis φ1, φ2, …, φj, … generated by a Löwdin transformation is characterized by the distance in Hilbert space between φj and φj. The choice of positive definite N12 minimizes these distances and maximizes the diagonal elements of N12. Again for positive definite N12 and a finite basis, 1 ? j ? p, the analysis yields a general theorem on Trace N?n2 (? p for all positive and negative integral values of n except n = ?1 and ? p for n = ?1).Sufficient conditions are determined which permit the application of the binomial theorem to the evaluation of the transform of H. Approximate formulas for the energy eigenvalues through third order in nondiagonal matrix elements are presented in a compact form containing characteristic nonorthogonality corrections depending on the exterior or interior location of the matrix element in the perturbation formulas.  相似文献   

6.
Quark masses     
In quark gluon theory with very small bare masses, -ψMψ, spontaneous breakdown of chiral symmetry generates sizable masses Mu, Md, Ms, … We find (Mu + Md) /2 ≈ mp/ √6 ≈ 312 MeV, and Ms ≈ 432 MeV. Scalar densities have well determined non-zero vaccum expectations 〈0|ua|0〉 ≡ 〈0|ψ(x) (λa/2)ψ(x)/0〉 ≈ ?π2Ma, i.e〈0? uo/vb0〉 ≈ 8 × 10?3 (GeV)3 at an SU(3) breaking of the vacuum c′ ≡ 〈0|u8|〉/〈0|uo|0〉 ≈ ? 16%  相似文献   

7.
The vibration-rotation transitions for v = 1 ← 0 of NO (2Π12) have been studied by using the technique of laser magnetic resonance spectroscopy. Five magnetic resonance lines are observed with three CO laser lines in the range from 1859 to 1886 cm?1. From these, three zero-field transition frequencies, v = 1 ← 0; R(32), P(72), and P(92) are obtained with an accuracy of ±0.0007 cm?1. The molecular constants which have been determined by borrowing centrifugal constants from a previous infrared work are B021 = 1.72004 ± 0.00006 cm?1, B121 = 1.70212 ± 0.00010 cm?1, and G(v = 1) ? G(v = 0) (for 2Π12) = 1875.8470 ± 0.0007 cm?1.  相似文献   

8.
We introduce the notion of uniform convergence of an operator sequence relative to a state operator, and we compare it with the notion of almost everywhere convergence, introduced by Gudder. We show that a sequence (Mn) of mean-value operators
Mn=1n∑ni=11?…?Ai?1?…,
defined on the infinite tensor product ?iHi, converges relative uniformly to x1 if and only if it converges almost everywhere to x1.  相似文献   

9.
In this paper we give a concrete realization for some examples of A.F.-algebras, such that the associated Bratteli-diagrams are those of ∑nk=lK(K1?…?Kk)? ?1Kk+1?…?1Kn. We also give a realization for any quotient of 2 ideals of the current algebra and obtain direct sums of C1-algebras of the given type.  相似文献   

10.
The method of multiple scales is used to analyze the response of a single-degree-of-freedom system to either the combination resonance of the additive type Ω2 + Ω1 ≈ ω0 or the combination resonance of the difference type Ω2 ? Ω1 ≈ ω0, where Ω1 and Ω2 are the frequencies of the excitation and ω0 is the linear undamped natural frequency of the system. To the second approximation, the combination resonance of the additive type has three effects on the steady state response. First, it produces terms having the frequencies Ω1, Ω2 and Ω2 + Ω1 at first order and terms having the frequencies 0, 1, 2Ω2, Ω2 ? Ω1, 2(Ω2 + Ω1), Ω2 + 2Ω1 and 2 + Ω1 at second order. Second, it produces a shift in the natural frequency of the system. Third, it produces a virtual primary-resonant excitation having the frequency Ω2 + Ω1 ≈ ω0 that makes the component having the frequency Ω2 + Ω1 be of first rather than second order. Similar effects are produced by a combination resonance of the difference type or a superharmonic resonance of order two.  相似文献   

11.
Hyperfine structure of the (0, 0, 1) - (1, 0, 1) transition of methanol has been investigated by beam absorption and of the (J, 1, 3?) → (J, 1, 3+) transitions for J = 2, 3, and 6 by beam-maser spectroscopy. The best-fit results for the spin-rotation and spin-spin coupling constants CJKτ±(i) and DJKτ±(i), respectively, are in kHz1: C101(1) = 2.4(10), C101(2) = ?0.6(10), D101(1) = ?13.8(9), D101(2) = 7.0(9), C213?(1) = ?5.0(10), C213?(2) = ?5.5(10) and (CJ13?(2) - CJ13+(2)) = 0.98(9).  相似文献   

12.
Relative oscillator strengths in the Cameron system of CO(a3Π ← X1Σ) have been observed in absorption for six bands (υ′ = 0–5, υ″ = 0) with the result, normalized to the absolute (0, 0) band measurement of Hasson and Nicholls, ?00 = (1.62±0.07) × 10?7, ?10 = (1.96±0.09) × 10?7, ?20 = (1.41±0.04) × 10?7, ?3 0 = (0.72±0.03) × 10?7, ?40 = (0.31±0.02) × 10?7, ?50 = (0.14±0.01) × 10?7. The density of CO was modulated with a motor-driven vacuum valve and synchronous fluctuations (?1 per cent) in the transmitted intensity detected with a lock-in amplifier. Peak pressure in the 21 cm absorption cell was approximately 10 torr. A curve of growth analysis was used to correct saturation effects by less than 3 per cent.  相似文献   

13.
In the framework of the six-quark model, based on the gauge group SU(2)L × U(1) we have obtained expressions for the amplitudes of K0 ? K0, D0 ? D0, B0 ? B BS0?BS0, T0?T0andTc0?TC0 transitions at final 4-momenta of external lines Feynman box diagrams. We have estimated the correctness of using the approximation of extremely small 4-,omenta of valence quarks, composing K0-like mesons. The constraints for the parameters of the unitary matrix of weak charged currents have been found at arbitrary value of the t-quark mass. Estimates of numerical values for the mixing parameters and for the parameters of CP violation for neutral systems similar to K0?K0 are given.  相似文献   

14.
A simple physical realization is found for the time-dependent harmonic oscillator equation q? + φ(t)q = 0, for its auxiliary equation g?9 + φ(t)? = h2??3, and for the Ermakov invariant. Through generalization of the model, a set of invariants is obtained for a system of equations of the form g?9i + φij(tj(t)qj = 0.  相似文献   

15.
The results of a vibrational and rotational analysis of the banded a?3A2X?1A1 transition in CH2SCD2S are presented. Only three of the six vibrational modes are active in the spectrum with ν′2 = 13201012, ν′3 = 859798, and 2ν′4 = 711516cm?1. The spin forbidden transition gains intensity primarily by a mixing of the 1A11,π) and 3A21,n) states. This is confirmed by a rotational analysis of the 000 band of both isotopes. The rotational analysis shows that the coupling in the a?3A2 state is near Hund's case b and that the spin constants are nearly 10 times greater than those observed for CH2O. A CNDO2 calculation shows that this difference is due to the greater spin orbit coupling of S in CH2S and to the smaller energy differences between the B?1A11,π), b?3A11,π), X?1A1, and the a?3A21,n) states. The r0 structure calculated from the rotational constants is rCS = 1.683 A?, rCH = 1.082 A?, βHCH = 119.6°, and α (out of plane) = 16.0°. A simultaneous fit of the vibrational levels in ν4 of CH2S and CD2S to a double minimum potential function yielded a barrier to molecular inversion of 13 cm?1 and an equilibrium out-of-plane angle of 15°.  相似文献   

16.
The nonlinear temperature and velocity profiles of a two-dimensional Boussinesq fluid heated from below are shown to be the sum or terms with periodicity Λcrn, with n = 1, 2, 3; their amplitudes are a function of ? = (Ra ? Rcra)Rcra. The results are in agreement with the observations of Bergé and Dubois.  相似文献   

17.
Medium resolution infrared grating spectra of gaseous ketene, H2CCO were recorded between 1000 and 400 cm?1, both at instrument temperature (40°C) and with cooling (?40°C). Interferometric Fourier spectra were also measured at ?70°C with resolution 0.22 cm?1 between 450 and 330 cm?1. The K structure of the fundamentals ν5, ν6, ν8, and ν9 was assigned. These fundamentals are coupled by a-axis Coriolis interactions. These couplings were analysed on the symmetric top basis for setting up the perturbation matrix and by utilizing the K-dependent Coriolis shifts of levels. A preliminary analysis of the Coriolis intensity anomalies was also undertaken.Band center values from combination differences are ν50 = 587.30 (27) and ν60 = 528.36 (39) cm?1. Synthetic spectra indicate the band origins of ν8 and ν9 to be close to 977.8 and 439.0 cm?1, respectively. Estimates of Coriolis coupling constants obtained from synthetic spectra are ζ58a = + 0.33 (5), ζ68a = + 0.714 (20), ζ59a = ? 0.774 (20), and ζ69a = ? 0.30 (2). Approximate ratios of unperturbed vibrational transition moments obtained from spectral simulations are M80:±iM50:±iM60:M90 ≈ +2:?9:+10:+0.5.  相似文献   

18.
The fundamental bands of the CF radical in the X2Π12 and X2Π32 electronic states were observed by using an infrared tunable diode laser as a source. Zeeman modulation could be used in detecting lines not only in the 2Π32 state, but also in 2Π12, because the CF radical deviates considerably from Hund's case (a). From the least-squares analysis of the observed spectra, the following molecular constants were obtained: Be = 1.416 704 (37) cm?1, αe = 0.018 419 (50) cm?1, re = 1.271 977 (17) A?, De = 6.68 (15) × 10?6cm?1, p0 = 0.008 580 (21) cm?1, p1 = 0.008 52 (11) cm?1, and ν0 = 1286.1281 (5) cm?1, with three standard errors in parentheses.  相似文献   

19.
The energy dependence of the KL0-KS0 transmission regeneration amplitudes on deuterons and neutrons in the momentum region 10–50 GeV/c is determined. The moduli of the modified transmission amplitudes are momentum dependent. These dependences are fitted by the expression Ajp?nj, where Aj and nj (j = d, n) are constants:
Ad=2.88 ±0.04 mb, nd=0.546±0.030, for deuterons,
An=1.97 ±0.14 mb, nn=0.530±0.019, for neutrons,
The amplitude phases do not depend on the kaon momentum and are equal to ?d = (?130.9 ± 2.7)°?n = (?132.3 ± 1.7)°. The mean value of the ratio of the total cross-section differences for K0 and K0 interactions with neutrons and protons is determined. The residues of the partial ω and ? amplitudes, which contribute to the kaon-nucleon interaction amplitudes, are also obtained.  相似文献   

20.
The generalised Gruneisen parameters γ′ = ?? log ω/??′ and γ″ = ?? log ω/??″ have been calculated for various normal mode frequencies using the force model for Zirconium obtained on Keating's approach. There is a general agreement between the normalised frequency distribution curve of Zirconium obtained on the present model and that of Bezdek et al. The temperature dependence of the effective Gruneisen functions γ?(T) and γ?| (T) has been calculated using the procedure of Blackman. The high temperature limits of γ?(T), γ?|(T) and γ?v are in good agreement with those obtained by Goldak et al. from an analysis of the thermal expansion data of Zirconium.  相似文献   

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