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1.
We speculate on a modification of Einstein's equations at distances related to the Planck length (GN)12(h?)12(c)-32 = lPl = 1.61 X 10-33 cm, mPl = ?c-1 (lPl)-1 = 2.18 X 10-5 g = 1.22 X 1019 GeV. The Planck mass arises spontaneously through the coupling of gravity to a system of scalar fields, in a scale invariant way.The same scalars generate all masses of leptons, quarks and vector bosons responsible for the matter interactions in the limit of weak gravitational fields.  相似文献   

2.
The magnetic moments of the 12+ isomers in 192, 196, 198, 200, 206Pb and of the 332+ isomer in 205Pb have been measured using the PAD technique. The results for the g-factors are: g(192) = ?0.173(2), g(196) = ?0.1600(15), g(198) = ?0.1552(15), g(200) = ?0.1512(15), g(206) = ?0.1496(18), and g(205) = ?0.148(5). As all states have a rather pure (νi132)?n configuration, the values reflect directly the νi132 orbital. They show a decrease towards the more neutron-deficient isotopes attributed to the reduced core polarisation as a result of decreasing occupation of the i132 neutron shell. The measured systematics are discussed regarding core polarisation, mesonic corrections, and small admixtures of core-excited states to the i132 wave function.  相似文献   

3.
The difference in g-factors for the 61+ and 81+(πh922) states in 210Po has been measured as (g6 ? g8)g8 = 2.0 ± 0.7%. This result represents a small violation of additivity. A value of g8 = 0.909 ± 0.011, independent of g6, was also obtained.  相似文献   

4.
5.
We prove a theorem concerning the energies of the 2S and 3D states in a potential V(r) = ?g2r + Vc(r), where Vc is a non-singular confining potential. If (ddr)3(r2Vc) is positive, then the 3D state lies above the 2S state, provided
ddr1rddr2Vc+rdVcdr < 0, ?r>0.
For Vc = rα, this corresponds to 0 < α < 2.  相似文献   

6.
The non-selective nature of the (α, nγ) reaction has been used to complement information from charged-particle reactions on the level structure of 88Y and 90Y. The γ-ray spectra were recorded with a 25 cm3 Ge(Li) detector at 90° to the beam using primarily targets of 85Rb2CO3 and 87Rb2CO3 and α-particle energies of 11.8, 12.2 and 13.0 MeV. The resulting transitions were accommodated in level schemes that involved primarily the following shell model configurations: p12)1g92)?1, g92)?1g92)1, p12)1p12)?1, f52)?1g92)?1 in 88Y and p12)1d52)1, πg(92)1d52)1,p12)1s12))1 in 90Y.  相似文献   

7.
The resonant 2-photon E(O+g) ← B(O+g) ← X(O+g) transition of I2 vapor has been studied by polarization spectroscopy, leading to a rotational analysis of the ν = 0–15 vibrational levels of the E state. The principal constants determined are Be = 19.9738(42) × 10-3, αe = 5.602(84) × 10-5, γe = 1.02(41) × 10-7, DeJ = 3.040(74) × 10-9cm-1, and re = 3.6470(5) A?.  相似文献   

8.
No perturbation between two valence states of NO has ever been identified, although many valence-Rydberg and several Rydberg-Rydberg perturbations have been extensively studied. The first valence-valence crossing to be experimentally documented for NO is reported here and occurs between the 15N18O B2Π (v = 18) and B2Δ (v = 1) levels. No level shifts larger than the detection limit of 0.1 cm?1 are observed at the crossings near J = 6.5 [B 2Π(F1) ~ B′ 2Δ(F2)] and J = 12.5 [B 2Π(F1) ~ B′ 2Δ(F1)]; two crossings involving higher rotational levels could not be examined. Semi-empirical calculations of spin-orbit and Coriolis perturbation matrix elements indicate that although the electronic part of the B 2Π ~ B′ 2Δ interaction is large, a small vibrational factor renders the 15N18O B (v = 18) ? B′ (v = 1) perturbation unobservable. Semi-empirical estimates are given for all perturbation matrix elements of the operators Σia?ili·si and B(L±S? ? J±L?) which connect states belonging to the configurations (σ2p)2(π2p)412p), (σ2p)(π2p)412p)2, and (σ2p)2(π2p)312p)2.  相似文献   

9.
Optical absorption spectra of Ni2+ in (NH4)2Mg(SO4)2·6H2O and Co2+ in Na2Zn(SO4)2·4H2O single crystals have been studied at room and liquid nitrogen temperatures. From the nature and position of the observed bands, a successful interpretation could be made assuming octahedral symmetry for both the ions in the crystals. The splitting observed for 3T1g(F) band in Ni2+ and 4T2g(F) band in Co2+ at liquid nitrogen temperature have been explained as due to spin-orbit interaction. The extra band observed at 16,325 cm-1 in the case of Ni2+ at low temperature has been interpreted to be the superposition of vibrational mode of SO2-4 radical on 3T1g(F) band. The observed band positions in both the crystals have been fitted with four parameters B, C, Dq and ζ.  相似文献   

10.
The simplest four-quark SU(2) ? U(1) models with an anomally-free heavy lepton sector can have two charged heavy leptons and one or two neutral leprons. Such models also explain the rise in R (the ratio of hadronic to muon pair production in e+e? collisions). We study some consequences of different choices of leptonic numbers for L1 and L2. In particular, we derive, the leptonic decay width when several final-stae leptons are massive; the cross section for e+e?L1L2 production; the branching ratio for e+e?L2L2e3μ+missing energy.  相似文献   

11.
A left-right symmetric SUL(3) × SUR(3) gauge model with leptons in the (3, 3) + (3, 3) representation is presented. The SUIL(2)×U(1) subgroup is practically the WS + GIM model for sin2?W38, with additional currents involving heavy leptons. μ is naturally suppressed and a new kind of νe?νμ oscillations is possible. τ and 3μ events can be related to one leptonic triplet. The model is naturally imbedded in exceptional groups.  相似文献   

12.
During the last few years many dynamical systems have been identified, that are completely integrable or even such to allow an explicit solution of the equations of motion. Some of these systems have the form of classical one-dimensional many-body problems with pair interactions; others are more general. All of them are related to Lie algebras, and in all known cases the property of integrability results from the presence of higher (hidden) symmetries. This review presents from a general and universal viewpoint the results obtained in this field during the last few years. Besides it contains some new results both of physical and mathematical interest.The main focus is on the one-dimensional models of n particles interacting pairwise via potentials V(q) = g2ν(q) of the following 5 types: νI(q)=q?2, νII(q)=a?2sinh2(aq), νIII(q)=a2/sin2(aq), νIV=a2P(aq), , νV(q)=q?22q2. Here P(q) is the Weierstrass function, so that the first 3 cases are merely subcases of the fourth. The system characterized by the Toda nearest-neighbor potential, gj2exp[-a(qj?qj+1)], is moreover considered. Various generalizations of these models, naturally suggested by their association with Lie algebras, are also treated.  相似文献   

13.
The absorption and fluorescence spectra of pyrazine have been observed in vapor, solution and crystal, and the vibrational structures have been analyzed in detail. The fluorescence spectrum consists of long progressions of the nontotally symmetric vibration ν5(b2g), and the absorption spectrum contains also the progression of the corresponding excited state vibration ν5(b2g. However, the pattern of the latter progression is unusual because of the highly anharmonic nature of the potential of the 1B3u state, which may be expressed by a functional form containing a quadratic term in the normal coordinate. All the experimental results suggest that the known vibronic interaction between the 1B3u(n,π1) state and the 1B1u(π, π1) state through the vibration ν2(b2g) is strong. The vibronic coupling and the potential of the 1B3u state were found to be very sensitive to solvent.  相似文献   

14.
The color bond structure of a quark-antiquark system is extended, in the long-range approximation, self-consistently to the baryonic three-quark bond structure for SU(3)c and generally to the N-quark bond structure for SU(N)c. The universal (N-independent) mass square eigenvalues for massless quarks are
M2=(HN)2?2mρ2α=13N?3να+constant, να=0,1,2,…
.  相似文献   

15.
Absorption and emission spectra of Mo2 were investigated using flash photolysis of the Mo(CO)6 molecule. Tentative vibrational and rotational analyses of the 98Mo2 spectra were performed. For the ground state, 1Σg+ type was proposed with ωe = 477.1 cm?1, re = 1.929 A?, and D0(Mo2) = 95 ± 15 kcal mole?1. The results were compared with theoretical calculations for Mo2 and experimental results for Cr2 obtained previously. It seems reasonable that the transition metal diatomic molecules of this type have a high bond order.  相似文献   

16.
The opportunity to test a new equation for the computation of the lattice energy and at the same time examine a disparity in the literature data for the enthalpy of formation of the azide ion, ΔHθ?(N3?) (g) was the motivation for this study. The results confirm our earlier calculation and show the new equation to be reliable. Thermodynamic data produced in the study take values: ΔHθ?(N3?)(g) = 144kJ mor?1ΔHθhyd(N3?) = ?315 KJ mol?1 or ΔHθhyd(N3?) = ?295 KJ mol?1UPOT(NaN3) = 732 kJ mol?1UPOT(KN3) = 659 kJ mol?1UPOT(RbN3) = 637 kJ mol?1UPOT(CsN3) = 612 kJ mol?1UPOT(TIN3) = 689 kJ mol?1. The lattice energies of azides whose enthalpies of formation are documented have been calculated as well as the enthalpy of formation of the azide radical.  相似文献   

17.
We derive the Salam-Weinberg model by gauging an internal simple supergroup SU(21). The theory uniquely assigns the correct SU(2)L ? U(1) eigenvalues for all leptons, fixes θW = 30°, generates the W±σ, Z0σ and Aσ together with the Higgs-Goldstone IL = 12 scalar multiplets as gauge fields, and imposes the standard spontaneous breakdown of SU(2)L ? U(1). The masses of intermediate bosons and fermions are directly generated by SU(21) universality, which also fixes the Higgs field coupling.  相似文献   

18.
The model assumes that when two high energy particles collide each behaves as a geometrical object which has a Gaussian density and is spherically symmetric except for the Lorentz-contraction in the incident direction. Folding the two spatial distribution together we obtain the slope (b) of the elastic diffraction peak in terms of the c.m. velocities (βi and βj) and the sizes (Ai and Aj) of the two incident particles. These sizes are assumed to have the experimental s-dependence of σtotπA2 for each reaction. The combined s-dependence of the σtot's and the β's gives the s-dependence of the elastic slope bij(s) = 12(Ai2βi2 + Aj2βj2)σijtot(s)σijtot(∞). This formula agrees with the experimental slope for p-p, p-p, K+-p, K?-p and π±-p elastic scattering from 3 to 1500 GeV/c, with only 3 parameters: Aπ2 = 6.1, AK2 = 3.3 and Ap2 = 10.5 (GeV/c)?2.  相似文献   

19.
Predissociations in the y1Πg and x1Σg? Rydberg states of N2 (configurations u?14pσ and u?13pπ, respectively) and their likely causes, are discussed. Peaking of rotational intensity at unusually low J values, without sharp breaking off, is interpreted as due to case c? or case ci predissociation. Λ doubling in the y state, attributed to interactions with the x1Σg? state and with another, 1Σ+, state of the same electron configuration as x, is analyzed. From this analysis the location of the (unobserved) 1Σg+ state, here labeled x′, is obtained. It is concluded that the predissociation in the Π+ levels of the y state is an indirect one mediated by the interaction with x′ coupled with predissociation of x′ by a 3Σg? state dissociating to 4S + 2P atoms: combined, however, with perturbation of the y state by the k1Πg Rydberg state (configuration g?14dπ), whose Π+ levels are completely predissociated.  相似文献   

20.
We propose an O(18) theory which is perturbatively unifiable and which accounts for the absence of right-handed families in the low-energy world. The theory predicts a fourth left-handed family as well as four right-handed families at energies near the weak scale. It also implies the existence of eight light neutrinos, all of which contribute to the width of the Z0. Cosmological arguments suggest that four of these neutrinos should have masses between 2 and 35 GeV, and that the other four should be much lighter. They also suggest the existence of a doubly charged scalar φ++ and a singly charged scalar φ+. Dramatic signatures include the production of four right-handed charged leptons and eight right-handed quarks, Z0 → v′R + vR → vRγ +_vRγ, and e+e?φ++ + φ??. The lightest right-handed charged quark should be surprinsingly long-lived (τ?10?2sec) for a particle of mass ? 100 GeV.  相似文献   

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