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1.
The vector analyzing power Ay and the two tensor analyzing powers Ayy and Axx have been measured for the three-body break-up reactions and . Two of the outgoing particles were identified and detected in coincidence at θlab = ±30°. The deuteron bombarding energy was Ed = 15 MeV. The measurements are backed up by a series of tests in order to prove the absence of false asymmetries. 相似文献
2.
J. Banaigs J. Berger L. Goldzahl T. Risser L. Vu-Hai M. Cottereau C. Le Brun 《Physics letters. [Part B]》1973,45(4):394-398
The reactions d + p → τ + π0 and d + p → τ + η0 were studied using the missing-mass method for incident deuteron momenta between 2.8 and . The angular distributions show a peak in the forward direction () and are flat in the backward direction. The differential cross sections at for both reactions show a maximum for total center-of-mass energies near 3.46 GeV. 相似文献
3.
M. Preiswerk R. Casparis B.Th. Leemann H. Rudin R. Wagner P. Zuprański 《Nuclear Physics A》1976,263(2):276-284
The angular distribution of the analyzing power in elastic scattering has been measured at a neutron energy of 14.2 MeV in the angular range 50° to 152° c.m. Neutrons with a polarization of approximately 0.5 were obtained from the reaction at a deuteron energy of 140 keV and lab emission angle of 82°. The reaction was induced by vector polarized douterons obtained from a source of polarized ions. The latter was of a conventional “atomic beam” type. The results show good agreement with the data on the charge symmetric process at a proton energy of 14.5 MeV. Comparison is also made with the theoretical calculations of Doleschall and of Pieper and a good agreement is found. 相似文献
4.
Three-body break-up in n-p final-state interaction regions has been investigated through the reactions . In all cases, the proton and the neutron were detected at the same angle in a kinematically complete experiment for a deuteron bombarding energy of 27.5 MeV. Helium and deuterium gas targets in a small gas cell cooled with liquid nitrogen were used. No indication of any possible contribution from the (isospin-forbidden) 1S0 p-n final-state interaction was observed in the first three reactions. For the 3He + d reaction, the data shown pronounced enhancements due to the p-n final-state interaction. In the forward regions the observed peaks are broader than the predictions of final-state interaction models. 相似文献
5.
G.C. Salzman J.C. Martin J.J. Jarmer J.E. Simmons Gerald G. Ohlsen T.R. Donoghue 《Physics letters. [Part B]》1973,45(2):123-126
We have measured the longitudinal neutron polarization in the reaction, at θ=0°, for an incident longitudinally polarized deuteron beam. A deuteron energy range of 3.3–14.9 MeV was covered. The polarization transfer from the deuteron to the neutron is found to be large, and the reaction is potentially useful as a source of polarized neutrons. 相似文献
6.
Angular distributions of γ-rays from the 2H(d, γ)4He reaction have been measured at the deuteron energies Ed = 6.05, 8.96 and 11.67 MeV with a 12.7 cm × 15.2 cm NaI(Tl) crystal enclosed in a Cerenkov anticoincidence shield. A least-square fit of the angular distributions indicates that the differential cross section is proportional to sin2θ cos2θ and that the process proceeds through an E2 transition of the type . 相似文献
7.
J. Carroll D.H. Fredrickson M. Goitein B. Macdonald V. Perez-Mendez A. Stetz C.A. Heusch R.V. Kline K.T. Mcdonald 《Nuclear Physics A》1978,305(2):502-508
The reaction was studied at incident proton energies of 377, 462 and 576 MeV. A comparison of our data with others suggests the existence of a sharp forward peak in θHe at 377 and 462 MeV, which is unexplained by the theory and disappears at higher energies. 相似文献
8.
We examine rescattering corrections to the single nucleon exchange model of backward p-d elastic scattering and find them to be important at all energies. Using realistic deuteron wave functions we conclude that the rise at Ep (lab) ~ 400–600 MeV results from another mechanism, possibly the opening of the channel. 相似文献
9.
The relativistic correction (RC) to the deuteron magnetic moment is calculated using the light-cone dynamics. The restrictions imposed by the angular condition on the electromagnetic current operator of the deuteron are discussed in detail. It is shown that the additive model for the current operator of interacting constituents is consistent with the angular condition only for the two first terms of the expansion of the “good” current component in powers of the momentum transfer q. The RC to μd is expressed through the matrix element of the “good” component j+ and is found to be equal to for realistic NN potentials. Taking account of RC decreases essentially the discrepancy between the theoretical and experimental values of μd. Possible solutions of the angular condition for squared q-terms of the j+ current component are also discussed. 相似文献
10.
Excitation functions at θ = 90° have been measured for , , and , in the range E3He = 3–19 MeV. The first reaction has also been studied at θ = 40°. Excitation functions at 90° have also been measured for and for E3He = 19–26 MeV. Angular distributions have been measured for the first four reactions.For the most excitation functions, a broad peak is observed, several MeV wide, centred at about Ex≈ 20 MeV. Superimposed on this, in some cases, are narrower peaks, with width ≈ 1 MeV. Energies and widths have been extracted for all resonances.Cluster-model calculations have been carried out, using methods similar to those which have proved successful for low-lying states in A= 18–19 nuclei. No satisfactory correspondence with the present results was found. The shell model has been used to calculate Γ3He and Γγ for 1?ω excitations in the final nuclei. These generally show good agreement with the trends of the experimental data. The results are consistent with the excitation of the giant dipole resonance in 3He capture, but much more weakly than in proton capture. 相似文献
11.
We study the potentials of the form U(r)=?r?1+λV(r), , and show that the energy levels satisfy the inequalities to first order in λ, where Nc denotes the coulombic principal quantum number and l the angular momentum. Similarly for potentials , we prove to first order in λ that , where NH denotes the harmonic oscillator quantum number. In the latter case, we give also quantitative restrictions on the relative positions at the lth and (l+1)th states. 相似文献
12.
G.W. Brandenburg W.B. Johnson D.W.G.S. Leith J.S. Loos J.A.J. Matthews F.C. Winkelmann R.J. Yamartino 《Physics letters. [Part B]》1973,44(3):305-309
Differential cross sections for center of mass scattering angles near 90° are presented for the reactions , and KL°p → KS°p in the momentum interval 1.0 to 7.5 GeV/c. The energy dependences of these cross sections are found to be equally well described by the parameterization: or . 相似文献
13.
Collisions between two excited atoms leading to an increase in the excitation energy of the particles have been under investigation. All measurements were made in the afterglow of gas-discharge plasma. The cross sections of the following reactions have been determined: . The cross section of the first reaction for different transitions lies in the region (2?35) × 10?15 cm2 and the cross section of the second, in (0.2?2.4) × 10?16 cm2. Possible systematic errors and the role of cascade transitions are discussed. Cross sections of the Penning reaction Hem + Xe0 → He0 + Xe+ + e have also been measured. The result is σ (23S) = (1.4 ± 0.2) × 10?15 cm2, σ (21S) = (1.2 ± 0.3) × 10?15 cm2. 相似文献
14.
The He2 band systems and are described in detail, and the i and l states characterized. A number of significant perturbations in the i and l states are identified, and the possible perturber states discussed. The following molecular constants (cm?1) are reported:
State | |||||
1707.95 | 35.00 | 7.242g | 0.222 | 1.0782 | |
1703.86 | 34.97 | 7.2264 | 0.2188 | 1.0794 |