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It is shown that for spinorial charges Q(L))α (α = 1, 2, L = 1, …, S) satisfying the commutation relations
{Q(L)α, Q(M)β} = εαβaLMQ,
{Q(L)α, Q(M)+β} = cσμαβPμδLM,
[Q(L))α, Pμ] = 0,
where Q is a scalar charge commuting with the spinor charges as well aswith the energy- momentum vector Pμ, there can exist several different multiplets for free massive scalar and spinor fields.  相似文献   

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If KS1,Lis a K1 resonance decaying into KS,L (the short- and long-lived kaon) and a neutral system So of pions, one can isolate the C-even and C-odd, crossed-channel contributions to KN → K1N by using the reactions KLN → KS1, LN whether So is a C-eigenstate, or a mixture of C-even and C-odd states. Applications to the production of K1(890) and the Q-meson are discussed, and simple numerical predictions made for QS,L production. Q-production data indicate approximate t-channel helicity conservation for the ω and P' exchanges at vertices involving a spin change, in similarity to the belief for the pomeron. QS,L production data can give information also on Q-decays.  相似文献   

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The emission and excitation spectra of the aromatic thioketone xanthione have been measured in Shpolskii matrices at 15 K. Under these conditions a sharp and rich vibrational structure is observed in the lowest triplet and the first and second excited singlet states. The phosphorescence excitation spectrum places the origin of the T1S0 transition at 15 143 cm?1, while that of the S1(n, π1) ← S0 absorption is tentatively assigned to the band at 16 093 cm?1. The phosphorescence spectrum, which shows only a weak CS stretch vibrational band, is dominated by ring vibrations. In accordance with the previous analysis of ODMR measurements, it is suggested that T1 and T2 states are energetically very close, thereby resulting in a lowest triplet state of heavily mixed n, π1, π1 character. No mirror-image relationship is found between the relatively strong S2S0 fluorescence and the excitation spectrum of the S2(π, π1) ← S0 transition. The latter is dominated by a long, pronounced 336-cm?1 progression.  相似文献   

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The transverse spin pair correlation function pxn=<SxmSxm+n>=<SxmSxm+n> is calculated exactly in the thermodynamic limit of the system described by the one-dimensional, isotropic, spin-12, XY Hamiltonian
H=?2Jl=1N(SxlSxl+1+SylSyl+1)
. It is found that at absolute zero temperature (T = 0), the correlation function ρxn for n ≥ 0 is given by
ρx2p=142π2pΠj=1p?14j24j2?12p?2jif n=2p
,
ρx2p+1142π2p+1Πj=1p4j24j2?12p+2jif n=2p+1
, where the plus sign applies when J is positive and the minus sign applies when J is negative. From these the asymptotic behavior as n → ∞ of |?xn| at T = 0 is derived to be xn| ~ an with a = 0.147088?. For finite temperatures, ρxn is calculated numerically. By using the results for ?xn, the transverse inverse correlation length and the wavenumber dependent transverse spin pair correlation function are also calculated exactly.  相似文献   

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Discharges through mixtures of helium and neon show two band groups near 4250 and 4100 Å as first observed by Druyvesteyn. These bands, assigned to the HeNe+ ion by Tanaka, Yoshino, and Freeman, have been studied under high resolution and have been fairly completely analyzed. The upper state of the transition is a very weakly bound state resulting from He+(2S) + Ne(1S0). There are two lower states resulting from the two components of Ne+(2P) + He(1S0). The upper of these two (2Π12) is also very weakly bound while the lower of the two, the 2Σ+ ground state, has a dissociation energy of 0.69 eV and an re value of 1.30 Å. All bands in both band groups show four branches designated Rff, Qef, Qfe, and Pee. From their analysis the rotational constants in the various vibrational levels of the three electronic states have been determined. While no spin splitting in the B2Σ+ state has been found the ground state X2Σ shows a very large spin splitting and the A22Π12 state a very large Ω-type doubling. The vibrational numberings in all these states were established by the study of the spectrum of 3HeNe+. At the same time the hyperfine structure observed in all lines of 3HeNe+ confirmed the nature of the upper state B2Σ+ as resulting from He+ + Ne, i.e., by charge exchange from the ground state. The 2Π12 component of the 2Π state has not been observed, presumably because of low intensity.  相似文献   

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The v = 1 ← 0 vibration-rotation bands of the NS radical in the X2Π12 and X2Π32 electronic states were observed by using a tunable diode laser. From the least-squares analysis the band origins were determined to be 1204.2755(12) and 1204.0892(19) cm?1, respectively, for X2Π12 and X2Π32. The rotational and centrifugal distortion constants and the internuclear distance in the X2Π electronic state were obtained as follows: Be = 0.775549(10) cm?1, De = 0.00000129(33) cm?1, and re = 1.49403(4) A?, with three standard deviations indicated in parentheses.  相似文献   

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