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1.
The cross-channel isospin amplitude is measured in the single reaction γn → ?0(pπ?) at 7.5 GeV assuming the ?0 dominance model. A low-mass enhancement is found for in the range of m(pπ?) of ~1.2 to ~1.7 GeV. The reaction strongly violates s-channel helicity conservation but is consistent with t-channel helicity conservation. The features are found to be very similar to those obtained in previous analyses of πp → π(Nπ) reactions. 相似文献
2.
A. Apostolakis R. Casali C. Caso Y. Goldschmidt-clermont L. Pape J.P. Porte A. Stergiou B. Tallini G. Vassiliadis H. Wenninger G. Grard V.P. Henri P. Herquet J. Kesteman S. Banerjee K.W.J. Barnham R. Beuselinck I. Butterworth A. Jacholkowska 《Physics letters. [Part B]》1977,66(2):185-190
We report the evidence for a narrow charged peak (5.5 s.d.), which we suggest calling the I, in the 6-prong-V0 topology of p interactions at 12 GeV/c. The mass, widht and the product of cross section σI times the branching ratio BR into the final state (Ksoτ±τ+τ? are found to be: , , σI·BR≈20 μbarn 相似文献
3.
The magnetic hyperfine splitting νM = |gμNBHF/h| of ; as a dilute impurity in Ni has been measured with nuclear magnetic resonance on oriented nuclei as 226.4(2) MHz. With the known hyperfine field BHF = ?264.4(3.9) kG corrected for hyperfine anomalies the g-factor and magnetic moment of 193mAu are deduced to be |g| = 1.123(17) and |μ| = 6.18(9) μN. 相似文献
4.
The radiative lifetimes of the and states of CO2+ were measured by means of the delayed coincidence method. Excitation was performed by a pulsed electron beam incident on CO2. The results of these measurements are 115 ± 5 nsec for the state and 126 ± 3 nsec for the state. 相似文献
5.
M. Cerrada A. González-Arroyo J.A. Rubio F.J. Yndurain 《Physics letters. [Part B]》1976,62(3):353-356
We show that if one uses a coupled channel parametrisation for the I = 0 S-wave in processes and KK? → KK? (the last deduced from a ) taking properly into account the analytic structure of these waves, then it is possible to fit simultaneously all cross-sections for the above processes, in the ranges for the first fit, for the second, for the last. None of the three usually claimed resonances ?, S1, ?′ show up in the corresponding eigenphase analysis. 相似文献
6.
Laser-induced fluorescence excitation has been used to measure Stark splittings of selected lines in the and band systems of H2CS in electric fields up to 13 kV/cm. The derived excited state a-axis dipole moments are 0.820 ± 0.007 D for the 41 level of the 1A2 state; 0.838 ± 0.008 D for the zeroth vibrational level of 1A2; and 0.534 ± 0.015 D for the zeroth vibrational level of the 3A2 state. These results are compared with the corresponding values of H2CO, and interpreted in terms of the changing localization of the π and orbitals accompanying electronic excitation. 相似文献
7.
H. Taureg G. Zech F. Dydak F.L. Navarria P. Steffen J. Steinberger H. Wahl E.G.H. Williams C. Geweniger K. Kleinknecht 《Physics letters. [Part B]》1976,65(1):92-96
The branching ratio has been determined to be (2.68±0.15)×10?3 for photon energies greater than 50 MeV in the KS0 rest frame. The decay KS0→π+π?γ is found to be dominated by the internal bremsstrahlung transition. The branching rato of a possible direct transition is found to be less than 0.06 × 10?3 at 90% confidence level for . 相似文献
8.
The magnetic hyperfine splitting νM = |gμNBHF/h| of ; in Fe has been measured with the technique of nuclear magnetic resonance on oriented nuclei as 320.4(1) MHz. With the known hyperfine field the magnetic moment of the ground state of 175Ta is deduced to be . 相似文献
9.
A.R.W McKellar 《Journal of Molecular Spectroscopy》1981,86(1):43-54
Magnetic dipole transitions between the and components of the ground electronic state of BrO have been detected using the technique of laser magnetic resonance on three CO2 laser lines between 964 and 970 cm?1. This is the first direct observation of the state in BrO. The spin-orbit splitting parameter, A, is determined to be ?967.9831(2) cm?1 for 79Br16O and ?967.9981(2) cm?1 for 81Br16O. Accurate values for the rotational constant , the hyperfine parameters () and d, the Λ-doubling parameter p, and the Zeeman parameter g| are also determined from an analysis of the measured spectra. 相似文献
10.
A synthetic germanium-doped crystal of α-quartz was subjected to an electro-diffusion process , 625°K), in which Ag+ ions were introduced along the crystal's optic axis (c). A 9800MHz electron paramagnetic resonance spectrum at room temperature, taken after room temperature x-irradiation, revealed the presence of a silver-compensated germanium center AGe?Ag with large, almost isotropic 107Ag and 109Ag hyperfine splittings (26.078, 30.112 mT for magnetic field B∥c). Measurement of the spin-Hamiltonian (i.e. matrices , , and discloses that a suitable model for the observed center utilizes germanium, substituted for silicon, with the accompanying silver interstitial in a nearby c-axis channel, and with electronic structure in which an appreciable admixture Ge4+?Ag0 to Ge3+?Ag+ exists. Estimates of the unpaired electron orbital are presented. 相似文献
11.
Nuclear spectroscopic quadrupole moments of the radioactive isotopes 131Cs, 132Cs, and 136Cs have been determined from the hyperfine structure of the state by the level crossing method. The results including a Sternheimer correction are: , , . The quadrupole moments of all the Cs isotopes from A = 131 to A = 137 are recalculated. It is shown, that nuclear quadrupole moments of a specific isotope obtained from different atomic P-states only agree within the limits of error after application of the Sternheimer correction. The increase of Qs with decreasing neutron number conforms with other observations and theoretical calculations stating that for elements around Z = 55 nuclear deformation develops below N = 82. The staggering of the sign of Qs may be interpreted as consequence of an oblate-prolate degeneracy of the nuclear energy surface. Some magnetic moments have been slightly improved: , (corrected for diamagnetism). 相似文献
12.
13.
Marek Danielewski Jaeosław Da̧bek Stanisł;aw Mrowec Grażyna Siemińska 《Solid State Ionics》1985,17(4):331-335
Using the re-equilibration kinetic method the chemical diffusion coefficient in nonstoichiometric chromium sesquisulfide, Cr2+yS3, has been determined as a function of temperature (1073–1373 K) and sulphur vapour pressure (10?104 Pa). It has been found that this coefficient is independent of sulphur pressure and can be described by the following empirical equation: . It has been shown that the mobility of the point defects inCr2+yS3 is independent of their concentration and that the self-diffusion coefficient of chromium in this sulfide has the following function of temperature and sulphur pressure: . (cm2s?1). 相似文献
14.
The magnetic hyperfine splitting vM=|gμNBHF/h| of 196mAu (jπ=12?; configuration ¦(π(; as dilute impurity in Ni has been determined with nuclear magnetic resonance on oriented nuclei as 96.0(2) MHz. With the known hyperfine field BHF = ?264.4(3.9) kG corrected for hyperfine anomalies the g-factor and magnetic moment of 196mAu are deduced to be |g| = 0.476(7) and |μ| = 5.72(8) μN. Taking into account the known magnetic properties of and isomeric states in the neighbouring odd Pt, Au and Hg nuclei the structure of the 12? state is discussed. 相似文献
15.
B. Hoekstra 《Solid State Communications》1976,18(4):469-471
Ferromagnetic resonance experiments on thin epitaxial films of Y2.85La0.15Fe3.75Ga1.25O12, grown by a vertical dipping technique, provide strong evidence for stratification of these films. Perpendicular resonance spectra recorded after etching off the magnetic film step by step show resonances due to six strata in 4 μm thick films. Of each stratum the thickness has been determined as well as the magnetic anisotropy. It is found that the layer next to the interface is 0.4 μm thick and has a strongly negative . Strata remote from the substrate are 1 μm thick and have a positive . 相似文献
16.
A. Ali 《Physics letters. [Part B]》1982,110(1):67-72
The QCD effective coupling constant αs(Q2) is determined by comparing the O(αs)2 jet-distributions with the high-energy e+e? data from PETRA. We get αs(Q2 = 1225 GeV2) = 0.125 ± 0.01, which corresponds to with five flavours. 相似文献
17.
A. Valentin A. Henry Ph. Cardinet M.F. Le Moal Da-Wun Chen K. Narahari Rao 《Journal of Molecular Spectroscopy》1978,70(1):9-17
The wavenumbers of the vibration rotation band lines of 14N16O are reported for the , and subbands of the 1-0 transition in the infrared. The full set of spectroscopic constants for this band has been determined by direct approach using the analysis of Zare, Schmeltekopf, Harrop, and Albritton. In addition to the band origin ν0 and the B, D, H constants for the lower and upper vibrational levels, the following spin-orbit coupling constants have been derived: and (in cm?1). Apparent centrifugal corrections to these constants have been determined and the values obtained for them are and . Λ-Type doubling constants evaluated by using both grating and tunable laser data are also reported. 相似文献
18.
The doubly odd nucleus 140Pr has been investigated by means of the 141Pr(d, t)140Pr and 140Ce(p, nγ)140Pr reactions. Twenty-eight levels, up to 1300 keV excitation, were observed in the pickup study. DWBA analysis was used to determine l-values and spectroscopic factors for all but a few which are very weakly populated. Gamma-ray angular distributions, measured at Ep = 4.78 MeV for the five strongest γ-rays, show appreciable nuclear alignment and demonstrate the feasibility of such experiments in this mass region. Taken together, the two studies have permitted the identification of the 12 levels expected from the low-lying (), (), () and (π1gν3s?1) configurations. Tenta assignments for the strong odd-parity states are suggested on the basis of their spectroscopic factors. 相似文献
19.
The 0-0, 1-1, 2-2, and 3-3 bands of the A2Π-X2Σ+ transition of the tritiated beryllium monohydride molecule have been observed at 5000 Å in emission using a beryllium hollow-cathode discharge in a He + T2 mixture. The rotational analysis of these bands yields the following principal molecular constants. From the pure electronic energy difference (EΠ - EΣ)BeT = 20 037.91 ± 1.5 cm?1 and the corresponding previously known values for BeH and BeD, the following electronic isotope shifts are derived and related to the theoretical approach given by Bunker to the problem of the breakdown of the Born-Oppenheimer approximation. 相似文献
20.
A red-degraded band head, normally badly overlapped by the gamma system, , of zirconium oxide, appears in emission spectra of zirconium arcs and in absorption spectra of S-type stars and of frozen rare gas matrices containing zirconium. The emission band has been examined at high-resolution with the aid of separated zirconium isotopes. Identification of the band as 0-0 of a system of zirconium oxide is confirmed by rotational analysis where the following constants (cm?1) are obtained for 90Zr16O: The Λ-type doubling in the 1Π state and the question of whether or is the true ground state of ZrO are discussed. 相似文献