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1.
It is observed that a simple mass formula of the formm =¯mQ 2(exp) is wholly consistent with experimental measurements and quark model estimates for all 12 fundamental fermions. Here¯m = 433.3 MeV is an input (mean fermion mass) constant,Q is the charge number of the lepton or quark, and is a real root of a quartic equation that brings in a principal quantum numbern (= 0, 1, 2, 3). The charged lepton masses are given accurately to within 0.3 of 1%, all neutrino masses are zero, and the top mass is predicted by the formula to be close tom t = 163.6 GeV.  相似文献   

2.
We calculate the minimum polynomial φ(x,y) of parasupercharge Q and Hamiltonian H for single-mode parabose parasupersymmetry (P-PSUSY). Suppose that φ(x,y) satisfies the homogeneity λ∈ℝ,φ(λ x,λ 2 y)=λ n φ(x,y), then the parafermionic order p f is restricted to either 1, 2, or 4. Under the P-PSUSY, the homogeneity of the φ(x,y) is equivalent to the parasuperconformality of Q and H. The physical meaning of the parasuperconformality is discussed, in connection with the spin of the elementary particle.  相似文献   

3.
We consider the families of entire transcendental maps given by F λ,m (z) = λz m exp(z), where m ≥ 2. All functions F λ,m have a superattracting fixed point at z = 0, and a critical point at z = −m. In the parameter planes we focus on the capture zones, i.e., λ values for which the critical point belongs to the basin of attraction of z = 0, denoted by A(0). In particular, we study the main capture zone (parameter values for which the critical point lies in the immediate basin, A *(0)) and prove that is bounded, connected and simply connected. All other capture zones are unbounded and simply connected. For each parameter λ in the main capture zone, A(0) consists of a single connected component with non-locally connected boundary. For all remaining values of λ, A *(0) is a quasidisk. On a different approach, we introduce some families of holomorphic maps of which serve as a model for F λ,m , in the sense that they are related by means of quasiconformal surgery to F λ,m . Both authors were supported by MTM2005-02139/Consolider (including a FEDER contribution) and CIRIT 2005 SGR01028. The first author was also supported by MTM2006-05849/Consolider (including a FEDER contribution).  相似文献   

4.
On Meson Masses     
G. V. Efimov 《Few-Body Systems》2007,40(3-4):131-143
It is shown that in the framework of an analytical confinement, when quark and gluon propagators are induced by a vacuum self-dual gluon field with constant strength, the masses of mesons with quantum numbers Q = (J P ,n), where n is the radial quantum number, and quark constituents m 1, m 2 are described with reasonable accuracy by the formula The positive parameter A Q is unique for all mesons with a fixed quantum number Q. Sets of mesons J P = 1, 0+, 1+, 2+, 3 for n = 0 and 1 , 2+ for n > 0 and different flavor constituent quarks (u = d, s, c, b) are considered.  相似文献   

5.
The thermal conductivity of diamond-paraffin wax composites prepared by infiltration of a hydrocarbon binder with the thermal conductivity λ m = 0.2 W m−1 K−1 into a dense bed of diamond particles (λ f ∼ 1500 W m−1 K−1) with sizes of 400 and 180 μm has been investigated. The calculations using universally accepted models considering isolated inclusions in a matrix have demonstrated that the best agreement with the measured values of the thermal conductivity of the composite λ = 10–12 W m−1 K−1 is achieved with the use of the differential effective medium model, the Maxwell mean field scheme gives a very underestimated calculated value of λ, and the effective medium theory leads to a very overestimated value. An agreement between the calculation and the experiment can be provided by constructing thermal conductivity functions. The calculation of the thermal conductivity at the percolation threshold has shown that the experimental thermal conductivity of the composites is higher than this critical value. It has been established that, for the composites with closely packed diamond particles (the volume fraction is ∼0.63 for a monodisperse binder), the use of the isolated particle model (Hasselman-Johnson and differential effective medium models) for calculating the thermal conductivity is not quite correct, because the model does not take into account the percolation component of the thermal conductivity. In particular, this holds true for the calculation of the heat conductance of diamond-matrix interfaces in diamond-metal composites with a high thermal conductivity.  相似文献   

6.
7.
This paper continues the analysis of the quantum states introduced in previous works and determined by the universal asymptotic structure of four-dimensional asymptotically flat vacuum spacetimes at null infinity M. It is now focused on the quantum state λ M , of a massless conformally coupled scalar field propagating in M. λ M is “holographically” induced in the bulk by the universal BMS-invariant state λ defined on the future null infinity of M. It is done by means of the correspondence between observables in the bulk and those on the boundary at future null infinity discussed in previous papers. This induction is possible when some requirements are fulfilled, in particular whenever the spacetime M and the associated unphysical one, M͂, are globally hyperbolic and M admits future time infinity i +. λ M coincides with Minkowski vacuum if M is Minkowski spacetime. It is now proved that, in the general case of a curved spacetime M, the state λ M enjoys the following further remarkable properties:
(i)  λ M is invariant under the (unit component of the Lie) group of isometries of the bulk spacetime M.
(ii)  λ M fulfills a natural energy-positivity condition with respect to every notion of Killing time (if any) in the bulk spacetime M: If M admits a time-like Killing vector, the associated one-parameter group of isometries is represented by a strongly-continuous unitary group in the GNS representation of λ M . The unitary group has positive self-adjoint generator without zero modes in the one-particle space. In this case λ M is a so-called regular ground state.
(iii)  λ M is (globally) Hadamard in M and thus it can be used as the starting point for the perturbative renormalisation procedure of QFT of in M.
  相似文献   

8.
We present new theoretical calculations of nuclear fusion rates λ f J from the resonant states of the muonic molecular ion 3He ++ with total angular momenta J=0,1. As a byproduct, new very accurate variational wave functions for these states have been obtained. Using these wave functions, the probability density |Ψ(R=0)|2 in a fusion region has been calculated by extrapolating the variational solution to small internuclear distances by means of the multi-channel adiabatic solution. Calculated fusion rates for the states J=0 and J=1 are: λ f 0 =1.9·105s-1 and λ f 1 =0.65·103s-1, respectively. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

9.
Asymptotic behaviors of zero modes of the massless Dirac operator H = α · D + Q(x) are discussed, where α = (α1, α2, α3) is the triple of 4 × 4 Dirac matrices, , and Q(x) = (q jk (x)) is a 4 × 4 Hermitian matrix-valued function with | q jk (x) | ≤ Cx−ρ, ρ > 1. We shall show that for every zero mode f, the asymptotic limit of |x|2 f (x) as |x| → + ∞ exists. The limit is expressed in terms of the Dirac matrices and an integral of Q(x) f (x).   相似文献   

10.
We present two rotating black hole solutions with axion ξ, dilaton f{\phi} and two U(1) vector fields. Starting from a non-rotating metric with three arbitrary parameters, which we have found previously, and applying the “Newman–Janis complex coordinate trick” we get a rotating metric g μν with four arbitrary parameters namely the mass M, the rotation parameter a and the charges electric Q E and magnetic Q M . Then we find a solution of the equations of motion having this g μν as metric. Our solution is asymptotically flat and has angular momentum J = M a, gyromagnetic ratio g = 2, two horizons, the singularities of the solution of Kerr, axion and dilaton singular only when r = a cos θ = 0 etc. By applying to our solution the S-duality transformation we get a new solution, whose axion, dilaton and vector fields have one more parameter. The metrics, the vector fields and the quantity l = x+ie-2f{\lambda=\xi+ie^{-2\phi}} of our solutions and the solution of: Sen for Q E , Sen for Q E and Q M , Kerr–Newman for Q E and Q M , Kerr, Reference Kyriakopoulos [Class. Quantum Grav. 23:7591, 2006, Eqs. (54–57)], Shapere, Trivedi and Wilczek, Gibbons–Maeda–Garfinkle–Horowitz–Strominger, Reissner–Nordstr?m, Schwarzschild are the same function of a, and two functions ρ 2 = r(r + b) + a 2 cos2 θ and Δ = r(r + b) − 2Mr + a 2 + c, of a, b and two functions for each vector field, and of a, b and d respectively, where a, b, c and d are constants. From our solutions several known solutions can be obtained for certain values of their parameters. It is shown that our two solutions satisfy the weak the dominant and the strong energy conditions outside and on the outer horizon and that all solutions with a metric of our form, whose parameters satisfy some relations satisfy also these energy conditions outside and on the outer horizon. This happens to all solutions given in the “Appendix”. Mass formulae for our solutions and for all solutions which are mentioned in the paper are given. One mass formula for each solution is of Smarr’s type and another a differential mass formula. Many solutions with metric, vector fields and λ of the same functional form, which include most physically interesting and well known solutions, are listed in an “Appendix”.  相似文献   

11.
In the reactions p-pπ 0 π 0, ηη, ηη′, in the mass region 1900–2400 MeV there are four relatively narrow resonances f 2(1920), f 2(2020), f 2(2240), and f 2(2300) and a broad one f 2(2000). In the framework of quark combinatorics, we carry out an analysis of the decay constants for all five resonances. It is shown that the relations for the decay constants corresponding to the broad resonance f 2(2000) → π 0 π 0, ηη, ηη′ are the same as those corresponding to a glueball. An additional argument in favor of the glueball nature of f 2(2000) is the fact that f 2(1920), f 2(2020), f 2(2240), and f 2(2300) fit well the q-q trajectories in the (n, M 2) plane (where n is the radial quantum number), while the broad f 2(2000) resonance turns out to be an unnecessary extra state for these trajectories. The text was submitted by the authors in English.  相似文献   

12.
New experimental data on the binding energyB λλ ofλλ6He, reported very recently, come up with the valuesB λλ = 725 ±0.14 MeV and ΔBλλ = 101 ±0.2 MeV which are substantially lower than the old dataB λλ = 109 ±0.8 MeV and ΔBλλ = 4.7±10 MeV in use in literature since 1966. In view of the new data we decided to undertake a re-study of the λλ 6 He hypernucleus using the same three-body model (α-λ-λ) with a simple coordinate space variational approach which was employed earlier with the old data onλλ/6He. After fitting different λ-λ potentials to the new data of λλ 6 He we have applied our method to study some double-λ hypernuclei in light, medium and heavy mass regions and have determined the structural quantities like Bλλ, the r.m.s. values of core-λ (〈rcore-λ〉〉) and λ-λ (〈rλ-λ〉〉) distances theoretically. The core-λ interaction considered is of Woods-Saxon type. The strength and the range of the core-A potential have been adjusted to reproduce the λ-binding energy(B λ) . These are in good agreement with the relativistic mean field (RMF) results. Our study shows that the λ-λ bonding energy ΔBλλ decreases with increasing mass number from λλ 10 Be to λλ 210 Pb of a double-A hypernucleus  相似文献   

13.
The electrical resistivity ρ and the thermopower S of ceramic materials LnBaCuFeO5 + δ (Ln= La, Pr, Nd, Sm, Gd-Lu) are measured in air at temperatures in the range from 300 to 1100 K. All the studied ferrocuprates are p-type semiconductors. The electrical resistivity ρ and the thermopower S of these compounds increase with a decrease in the radius of the Ln 3+ cation (with an increase in the number of 4f electrons n in Ln 3+). The nonmonotonic behavior of the dependences ρ=f(n) and S=f(n) indicates that the electrical properties of the layered ferrocuprates LnBaCuFeO5 + δ depend on the electronic configuration of the Ln 3+ cation. The power factors P calculated for the LnBaCuFeO5 + δ ceramic materials from the experimental values of ρ and S increase with increasing temperature and, at T = 1000 K, reach the maximum values P = 102.0 and 54.1 μW m−1 K−2 for Ln = Pr(4f 2) and Sm(4f 5), respectively, and become close to each other and equal to 30–35 μW m−1 K−2 for Ln = Gd(4f 7), Dy(4f 9), and Ho(4f 10).  相似文献   

14.
We investigate the possibility of calculating the fermion and the gauge-boson masses within an electroweakSU(2)L ×U(1)Y gauge-invariant model without the Higgs fields. Instead of the whole Higgs sector we introduce one Abelian vector boson C with massM renormalizably interacting with leptons and quarks of chiralities L and R with a strengthh. An interplay of all interactions which contribute to the fermion masses results in the fermion mass formulam f= =M exp[872/(3y(f L)y(f R)h 2)], wherey(f L,R) are the C hypercharges, and y(fL). y(f R) < 0. The intermediate-boson massesm w andm z are expressed in terms of the fermion masses via sum rules.Invited talk presented at the International Conference Selected Topics in Quantum Field Theory and Mathematical Physics, Bechyn, Czechoslovakia, June 23–27, 1986.  相似文献   

15.
The excess 1/f noise in a random lattice with bond resistances r∼exp(−λx), where x is a random variable and λ≪1, is studied theoretically. It is shown that if the correlation function {δr 2}∼r r θ+2, then the relative spectral density of the noise in the system is expressed as C e∼λm exp(−λ(1−p c)), where p c is the percolation threshold and md (ν is the critical exponent of the correlation length and d is the dimensionality of the problem). It is hypothesized that the exponent m possesses a dual universality: It is independent of 1) the geometry of the lattice and 2) the θ-mechanism responsible for the generation of the local noise. Numerical modeling in a three-dimensional lattice gives m=52.3 for θ=1 and θ=0, in agreement with the hypothesis. Pis’ma Zh. éksp. Teor. Fiz. 63, No. 8, 614–618 (25 April 1996)  相似文献   

16.
In this paper, we study the asymptotic behavior of solutions of semilinear abstract differential equations (*) u′(t) = Au(t) + t n f(t, u(t)), where A is the generator of a C 0-semigroup (or group) T(·), f(·, x) ∈ A for each xX, A is the class of almost periodic, almost automorphic or Levitan almost periodic Banach space valued functions ϕ: ℝ → X and n ∈ {0, 1, 2, ...}. We investigate the linear case when T(·)x is almost periodic for each xX; and the semilinear case when T(·) is an asymptotically stable C 0-semigroup, n = 0 and f(·, x) satisfies a Lipschitz condition. Also, in the linear case, we investigate (*) when ϕ belongs to a Stepanov class S p-A defined similarly to the case of S p-almost periodic functions. Under certain conditions, we show that the solutions of (*) belong to A u:= ABUC(ℝ, X) if n = 0 and to t n A uw n C 0 (ℝ, X) if n ∈ ℕ, where w n(t) = (1 + |t|)n. The results are new for the case n ∈ ℕ and extend many recent ones in the case n = 0. Dedicated to the memory of B. M. Levitan  相似文献   

17.
The exponent λ of the structure function F2x −λ is calculated using the solution of the DGLAP equation for gluon at lowx reported recently by the present authors. The quantity λ is calculated both as a function ofx at fixedQ 2 and as a function ofQ 2 at fixedx and compared with the most recent data from H1  相似文献   

18.
By using the thermo entangled state representation we solve the master equation for a dissipative cavity with Kerr medium to obtain density operators’ infinite operator-sum representation ρ(t)=∑ m,n,l=0 M m,n,l ρ 0 m,n,l . It is noticeable that M m,n,l is not Hermite conjugate to ℳ m,n,l , nevertheless the normalization ∑ m,n,l=0 n,m,l M m,n,l =1 still holds, i.e., they are trace-preserving in a general sense. This example may stimulate further studying if general superoperator theory needs modification.  相似文献   

19.
The mass spectra of secondary cluster ions Bi n + (n = 1–9) from bismuth sputtered by (6–21) keV Au m (m = 1–9) and Bi m (m = 1–5) cluster ions have been investigated. New features of manifestation of dense nonlinear cascades and thermal spikes have been revealed. It is concluded that the thermal spike regime makes a significant contribution to the mechanism of formation of small cluster ions, containing up to seven atoms for a bismuth target.  相似文献   

20.
We present results from a simulation of SU(2) lattice gauge theory with N f = 4 flavors of Wilson fermion and non-zero quark chemical potential μ, using the same 123×24 lattice, bare gauge coupling, and pion mass in cut-off units as a previous study (S. Hands, S. Kim, J.I. Skullerud, Phys. Rev. D 81, 091502(R) (2010)) with N f = 2 . The string tension for N f = 4 is found to be considerably smaller implying smoother gauge field configurations. Thermodynamic observables and order parameters for superfluidity and color deconfinement are studied, and comparisons drawn between the two theories. Results for quark density and pressure as functions of μ are qualitatively similar for N f = 2 and N f = 4 ; in both cases there is evidence for a phase in which baryonic matter is simultaneously degenerate and confined. Results for the stress-energy tensor, however, suggest that while N f = 2 has a regime where dilute matter is non-relativistic and weakly interacting, N f = 4 matter is relativistic and strongly interacting for all values of μ above onset.  相似文献   

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